lion tons of waste per year. Some of it, especially asphalt,
concrete, bricks, and metal, is already recycled because
there is a market for it, but vast amount of shingles,
carpet, wallboard, doors, windows, and other
pieces of homes and offices find their way into landfills
because the resale and recyclable market is poor. Between
65 and 85 percent of construction debris ends
up in landfills. Concrete and masonry can instead be
crushed and used as aggregate for road building. Glass
can be recycled into “glassphalt” road surface reflectors.
Wood becomes mulch. Pulverized wood helps the composting
of sludge at sewage treatment facilities.
Drywall (gypsum wallboard) disposal can pose an
environmental danger. Many landfills won’t accept gypsum
wallboard scrap because it produces toxic hydrogen
sulfide gas when buried. However, it can be recycled,
with up to 85 percent of the material reused for
new gypsum wallboard. Unpainted drywall can also be
composted, replacing lime in the soil.
Manufacturers currently sponsor programs that take
back used carpet, which is ground up for attic insulation
or recycled into new carpet. Plate glass becomes
fiberglass insulation. Acoustic tiles can be recycled into
new acoustic tiles.
Many new building materials can be made from
recycled materials. Scrap metal containing iron is used
to make reinforcing bars for concrete. Newsprint is
chopped into small pieces to become cellulose insulation.
Recycled plastic products include fence posts,
speed bumps, deck planking, and park benches. Incinerator
ash is used in nonstructural concrete. Even yogurt
containers with aluminum seal scraps can become
terrazzo-like floors. Look for opportunities to use recycled
materials in your designs.
Demolition by hand salvage produces useful
building components and even some architectural
gems. The dismantling of a building generates reusable
roof boards, framing lumber, and tongue-and-groove
wood flooring. Doors, windows, bathroom fixtures,
plywood, siding, and bricks can all be reused. Furniture,
equipment, and appliances can be reused. When checking
out a building for a renovation project, consider
which elements can be reused in your design or salvaged
for another project.
Some contractors sort excess or used building material
into bins right at the site, and reuse and recycle
what they can. This isn’t always possible in crowded urban
areas where projects take up every square inch of
space. Massachusetts, Florida, North Carolina, and California
have embarked on state-mandated construction
recycling programs, including grants to nonprofit retailers.
Despite the need to build recycling markets and
to develop strategies for dealing with wood covered with
toxic lead paint, asbestos, or other nonrecyclables, construction-
recycling programs promise to extend the lives
of overcrowded landfills. The donated materials may
also provide a tax deduction, and can help build affordable
housing.
In some communities, demolition auctioneers
arrange for do-it-yourselfers to deconstruct buildings by
hand and take away salvageable materials. Deconstruction
specialists say they can take most homes and many
other buildings to their foundations, saving 80 percent
or more of the material for resale or reprocessing. Some
communities train welfare recipients for deconstruction
jobs, which can eventually lead to carpentry apprentice
programs and careers in construction. Although deconstruction
takes longer than conventional demolition,
the salvaged materials can often offset increased labor
costs.
According to a 2001 report by the U.S. Department
of Housing and Urban Development (HUD) that examines
deconstruction activities in El Paso, Miami, Milwaukee,
and Nashville, deconstruction fosters the creation
and expansion of small businesses to handle the
salvaged material from deconstruction projects. Reusing
building materials can benefit the environment by diverting
valuable resources from crowded landfills into
profitable uses, which in turn would enable deconstruction
to pay for itself by generating revenues and reducing
landfill and disposal costs.
PLANNING FOR RECYCLING
The design of a building includes tracking the flow of
supplies in and of refuse out. Solid wastes can take up
more space than the water-borne waste systems we have
discussed. The accumulation of solid wastes in a building
can create fire danger, and their removal may present
severe local environmental problems. The separation
of solid waste to permit resource recovery has
significant energy and environmental consequences. It
is now common to install mechanical equipment for
handling solid waste in buildings.
Since the late 1940s, the amount of packaging material
used for consumer products has greatly increased.
We buy food in bags and cans that we then discard. Individual
packaging takes up more space in stores than
does bulk storage. Wastes are stored in the home until
collection day, requiring increased space allocation. It
takes energy to make and transport packaging and to
collect trash. Trash compactors take up space and use
electricity. Landfills continue to fill up, releasing methane
and leaching out chemicals.
High-grade resources are valuable materials that can
be recycled. Paper and some plastics can be collected
and stored within the building. Glass bottles can be returned
for reuse or recycling. If recyclable materials are
kept separate at the site of their use, resource recovery
is much easier. Glass bottles should be washed for reuse,
not broken and recycled.
Recycled paperboard (cardboard or pasteboard)
saves 50 percent of the energy required to process pulp
from wood. Recycled aluminum saves an astounding 96
percent of the electrical energy required for its original
production. A 52-percent energy savings is achieved by
recycling steel.
Wood scrap chopped into wood fiber is worth more
than when it is burned as a fuel. Oriented strand board
(OSB), made of wood chips and scraps, is used in the
manufacture of structural insulated panels (SIPs), window
frames, and other building products. Plastics are
more difficult to recycle. Due to consumer preferences
and regulations, recycled plastic is not often used in
food-related items. Recycled plastic pellets are used in
toys, building materials, and sports products. Recycled
plastic bottles are used in fabrics and some carpets.
It is possible to burn for fuel some materials that
are impractical to recycle. These are referred to as lowgrade
resources, and include gaseous wastes, liquid and
semiliquid wastes, and solid wastes.
Some industrial wastes give off a lot of heat when you burn them, but
some are very toxic. Some cities use the heat generated
by burning rubbish to fuel electric power plants or central
heating installations. Trash burning is limited by environmental
regulations. Burning vinyl wallcoverings
poses serious environmental problems.
When composted in landfills, some of these materials
produce methane gas, which can be collected for
use as a high-grade fuel. Cities extract methane gas from
old garbage dumps by drilling wells to tap underground
pockets of decomposition gas. The quantities produced
by livestock farming or sewage treatment plants are adequate
to justify building gas-generating equipment.
Many municipal water treatment plants are heated,
illuminated, and powered by methane gas from the
plants’ digesters.
Incineration reduces the volume of materials that
are sent to landfills. Incinerator plants are fed by dumping
wastes down a chute, where they are consumed by
a gas- or oil-fueled fire at the bottom. The resulting toxic
ashes are then carried out of the building. Incinerators
can create air pollution and are rarely installed in buildings
because of the strict regulations.
Sorting and storing recyclable materials within the
building requires more time and effort by the building’s
occupants. In an urban apartment, space and odor issues
can make recycling difficult. Containers for different
recyclables take up floor or cabinet space. A good
community recycling program with curbside pickup
helps keep accumulation down and provides some organization
to the process. Some recycling programs are
set up to recycle valuables in the trash automatically by
mechanized sorting.
SOLID WASTE COLLECTION
IN SMALL BUILDINGS
Most of the waste in a home comes from the kitchen.
Finding recycling space within a pantry, air-lock entry,
or cabinet or closet that opens to the outside makes
daily contributions easier, facilitates weekly removal,
and simplifies cleaning
Trash compactors take up space in the kitchen, and
may have odor and noise problems. Some trash compactors
have a forced-air, activated-charcoal filter to help
control odors, and sound insulation to control noise. A
trash compactor requires a grounded electrical outlet.
Garbage disposals are often installed below the
kitchen sink, frequently along with the dishwasher. The
garbage disposal grinds organic food scraps, mixes them
with water, and flushes them to the sewer. Waste with
less moisture goes into the garbage can. The finely
chopped organic matter biodegrades better at the
sewage treatment plant than it would at a landfill. However,
the garbage disposal uses energy and water—2 to
4 gallons for each minute of operation. The water co-
agulates grease so that it can be chopped, washes the
blade, and cools the motor. More energy is used when
the waste reaches the sewage treatment plant.
If you specify a garbage disposal, look for one with
adequate motor horsepower and grind chamber capacity
to grind quickly and efficiently. Deluxe disposal
models use stainless steel extensively in the grind system
to prevent corrosion. Insulated sound shells shield
grind chamber noise, and some models offer a secondary
sound baffle. Disposals require an electrical connection,
usually a 120V, 60-Hz, AC, 15- or 20-A threewire
grounded circuit.
An alternative to the garbage disposal is the compost
pile. Composting is a controlled process of decomposition
of organic material. Naturally occurring
soil organisms recycle nitrogen, potash, phosphorus,
and other plant nutrients as they break down the material
into humus. When decomposition is complete, a
dark brown, powdery material called humus has been
produced. As you can tell by its rich earthy aroma, the
finished compost is full of nutrients essential for the
healthy growth of plants and crops. Compost happens
as long as there is air and water to support it.
Composting is a convenient, beneficial, and inexpensive
way to handle organic waste and help the environment.
Composting reduces the volume of garbage
requiring disposal, saves money in reduced soil purchases
and reduced local disposal costs, and enriches
the soil. Self-contained units are available, and some
community groups sell bins made from recycled plastics
for very reasonable prices. Food wastes can be collected
in a covered container beside or under the sink.
Meats and animal wastes usually are not included, as
they attract animals and create odors. Collected food
wastes are then carried to the compost pile, where they
slowly decompose into clean, rich soil for gardens. Yard
wastes (leaves, grass clippings) are also added. The compost
pile should have a cover, to keep out unwanted animals.
The odor of a well-maintained compost pile is
not unpleasant, and the compost itself has a pleasing
earthy smell.
Vermiculture is a simple, if somewhat unusual,
method of using worms to turn kitchen waste into extremely
rich castings for use in the garden. The vericulture
bin is a very effective means of reducing the amount
of waste that goes into the landfill while also producing
an organic fertilizer to return to the earth. Red wiggler
worms are placed in one section of the worm box
with wet, shredded newspaper. Food scraps from the
kitchen are added to the box as they accumulate. Worms
feed on fruit and vegetable peels, tea bags, coffee
grounds, and pulverized eggshells, and can consume ap-
proximately half of their body weight per day. With one
pound of worms, approximately one pound of soil can
be removed from the box each month, while the worms
stay behind to carry on the process.
Garbage compactors are designed to cut down on
storage space for solid wastes. They can be used to compact
separated items for recycling, such as aluminum,
ferrous metals, and box cardboard. When dissimilar materials
are crushed together, recycling becomes difficult.
In a single family home, a garbage compactor may not
save more space than it takes up, but small stores and
businesses may find one beneficial.
LARGE BUILDING SOLID
WASTE COLLECTION
Large apartment complexes fence in their garbage can
areas to keep out dogs and other pests. This area is a
good place for bins for recycling, and even a compost
pile for landscaping. The solid waste storage area needs
garbage truck access and noise control, and should be
located with concern for wind direction to control
odors.
Both the building’s occupants and the custodial staff
must cooperate for successful recycling in a large building.
Office building operations generate large quantities
of recyclable white paper, newspaper, and box cardboard,
along with nonrecyclable but burnable trash, including
floor sweepings. Offices also produce food
scraps (including coffee grounds) and metals and glass
from food containers. Dumping this all into one collection
bin saves space, but with high landfill use costs,
separation and recycling spaces are becoming more and
more common.
The collection process for recycling in larger buildings
has three stages (Fig. 12-2). First, white paper, recyclables,
compostables, and garbage are deposited in
separate compartments near the employees’ desks. In
order to make an office building recycling system work,
the interior designer must often design a whole series
of multiple bins and the trails that connect them. Office
systems manufacturers are beginning to address
some of these needs. The process often needs to be coordinated
with the sources of the materials, such as paper
suppliers, and with the recycling contractors who
pick them up.
Next, custodians dump the separate bins in a collection
cart. There are also bins for white paper in the
computer and copy rooms and for compostables and
garbage in the employee lunchroom. Floor sweepings
are added to the garbage. The custodians take the full
cart to a service closet at the building’s core and deposit
each type of separated waste in a larger bin. The storage
closet also has a service sink to wash the garbage bins,
and may have a paper shredder.
Finally, white paper is shredded and stored for collection
by recycling and garbage trucks at the ground
floor service entrance, near the freight elevator. Compostables
are stored or sent to a roof garden compost
pile. Garbage is compacted and bagged. Compactors reduce
wastes to as little as a tenth of their original volume.
The storage area should be supplied with cool, dry,
fresh air. Compactors and shredders are noisy and generate
heat, and must be vibration-isolated from the
floor. A sprinkler fire protection system may be required,
and a disinfecting spray may be necessary. Access to a
floor drain and water for washing is a good idea.
In some buildings, wastes are ground and transported
by a system of very large vacuum pipes, which
suck the wastes to a central location for incineration or
compression into bales. Garbage grinders flush scraps
into sewers, adding to sewage system loads.
The renovation of a late nineteenth century New
York building for the National Audubon Society is an
excellent example of making recycling work. Designed
by the Croxton Collaborative, the eight-story building
was renovated in the 1990s. The collection system uses
two desktop paper trays, one for reuse and one for recycling.
Central recycling points are located near four
vertical chutes that pass through each floor. The chutes
carry collected materials to a subbasement resource recovery
center for recycling. The one for white paper is
near the copier. Food wastes and soft soiled paper, returnable
plastic bottles and aluminum cans, and mixed
paper (colored paper, file folders, paperboard, and selfstick
notes) are all collected in a pantry area near staff
kitchens. Shelves in the pantry hold returnable glass bottles,
coated papers (from juice and milk cartons), magazines,
and newspapers.
Custodians pick up the wastebasket contents from
work areas and the materials from the pantries, and take
them to the subbasement to sort. In the subbasement,
large movable bins collect material dropped down the
chutes. Glass bottles, newspapers, and other items are
boxed or baled. Recycled materials are taken to the delivery
dock for pickup by recycling and garbage collectors.
Organic wastes are refrigerated until enough accumulates
for screening and adding to a composter.
This composter is closed for odor control, but supplied with
air for aerobic digestion. After about three months, the
waste turns to humus and is used for a roof garden.
Food and organic waste represents a significant
portion of the waste stream, and states and communities
are creating opportunities for businesses to begin
organic waste diversion programs. In Boston, Slade
Gorton fishing company has established an effective
source-separation process that captured 15 tons of fish
by-products in its first two months. The Massachusetts
Institute of Technology implemented a pilot sourceseparation
system in the year 2000 in the primary oncampus
dining hall. Food preparation waste from the
kitchen is collected daily for composting, helping MIT
to achieve its 30 percent recycling goal and reducing
the cost of waste disposal. MIT is now developing plans
to divert all of the school’s organic waste, including
yard waste and food, for composting. This will help to
maximize recycling while minimizing costs, odor complaints,
and the need for workers to carry all that trash.
Interior designers are often involved in the selection and
specification of plumbing fixtures. Let’s start our discussion
of this topic with a brief look at the history of
plumbing fixtures. Indoor bathrooms were not common in homes until
around 1875, but their history goes back thousands
of years. Archeologists in Scotland’s Orkney Islands
discovered a latrine-like plumbing system dating to
8000 BC that carried wastes from stone huts to streams
in a series of crude drains. Hygiene has been a religious
imperative for Hindus since 3000 BC, when many homes
in India had private bathroom facilities. In the Indus
Valley of Pakistan, archeologists have found ancient private
and public baths fitted with terracotta pipes encased
in brickwork, with taps controlling the flow of
water.
The most sophisticated early baths belonged to
Minoan royal families. In their palace at Knossos on
Crete, bathtubs were filled and emptied by vertical stone
pipes cemented at their joints. These were eventually replaced
by pottery pipes slotted together much like modern
pipes. They provided both hot and cold water, and
removed drainage waste from the royal palace. The
Minoans also had the first flush toilet, a latrine with an
overhead reservoir fed by trapping rainwater or by filling
with buckets from a cistern.
By 1500 BC, aristocratic Egyptian homes used copper
pipes for hot and cold water. Whole-body bathing
was part of religious ceremonies, and priests were required
to immerse themselves in cold water four times
a day. The Mosaic Law of the Jews (1000–930 BC) related
bodily cleanliness to moral purity, and complex
public waterworks were built throughout Palestine
under the rule of David and Solomon.
Bathing became a social occasion in the second
century BC in Rome, when massive public bath complexes
included gardens, shops, libraries, exercise
rooms and lounge areas for poetry readings. The Baths
of Caracalla offered body oiling and scraping salons;
hot, warm, and cold tubs; sweating rooms; hair shampooing,
setting, and curling areas; manicure shops; and
a gymnasium. Shops sold cosmetics and perfumes. Up
to 2500 members at a time visited the spas and the adjacent
gallery of Greek and Roman art, library, and lecture
hall. In another room, slaves served food and wine
to spa visitors. All of this was only for men, but women
had their own smaller spa nearby. Eventually, men and
women mixed at spas, but apparently without major
promiscuous behavior, a practice that lasted well into
the Christian era until the Catholic Church began to
dictate state policy.
Plumbing Fixtures
ing barbarians destroyed most tiled baths and terracotta
aqueducts, leading to a decline in bathing and
personal cleanliness during the Middle Ages. The
Christian view at the time emphasized the mortification
of the flesh, and whole-body bathing was linked
to temptation and sin. Nobody bathed, but the rich
used perfume to cover body odors. Outhouses, outdoor
latrines and trenches, and chamber pots replaced
indoor toilets. Christian prudery and medical superstitions
about the evils of bathing led to an end to sanitation
and the rise of disease and epidemics. In the
1500s, the Reformation’s emphasis on avoiding sin
and temptation led people to expose as little skin as
possible to soap and water. There was almost no bathroom
plumbing, even in grand European palaces. A
1589 English royal court public warning posted in the
palace, and quoted in Charles Panati’s Extraordinary
Origins of Everyday Things (Harper & Row, Publishers,
New York, 1987, p. 202), read, “Let no one, whoever,
he may be, before, at, or after meals, early or late, foul
the staircases, corridors, or closets with urine or other
filth.” Apparently this was quite a common problem.
Around 1700, a French journal cited by the same
source noted, “Paris is dreadful. The streets smell so
bad that you cannot go out. . . . The multitude of people
in the street produces a stench so detestable that it
cannot be endured.”
From medieval times on, wastes from chamber pots
were tossed into streets. Legally, wastes were supposed
to be collected early in the morning by night soil men,
who carted them to large public cesspools, but many
people avoided the cost of this service by throwing waste
into the streets. Many cartoons of the period show the
dangers of walking under second story windows late at
night. Ladies kept to the inside of sidewalks to avoid the
foul gutters.
By the 1600s, plumbing technology reappeared in
parts of Europe, but indoor bathrooms did not. The initial
seventeenth century construction of Versailles included
a system of cascading and gushing outdoor water
fountains, but did not include plumbing for toilets and
bathrooms for the French royal family, 1000 nobles, and
4000 attendants who lived there.
Urbanization and industrialization in Britain in the
1700s resulted in overcrowding and squalor in cities.
There was no home or public sanitation, and picturesque
villages turned into disease-plagued slums. Cholera decimated
London in the 1830s, and officials began a campaign
for sanitation in homes, workplaces, public streets,
and parks. Throughout the rest of the nineteenth century,
British engineers led the western world in public
and private plumbing innovations.
PLUMBING FIXTURE SELECTION
AND INSTALLATION
On commercial projects, the architect and mechanical
engineer usually select and specify plumbing fixtures.
On residential projects, the interior designer or architect
helps the client with the selection. The interior designer
is often the key contact with the client for the selection
of fixtures, representing their preferences and
providing specification information to the engineer.
Kitchen and bath designers, who usually work for businesses
selling fixtures, often help owners select residential
fixtures on renovation projects.
Several inspections by the local building inspector
are required during the construction process, to assure
that the plumbing is properly installed. Roughing-in is
the process of getting all the pipes installed, capped, and
pressure-tested for leaks before the actual fixtures are installed.
The interior designer should check at this point
to make sure the plumbing for the fixtures is in the correct
location and at the correct height. The first inspection
usually takes place after roughing-in the plumbing.
The contractor must schedule the inspector for a prompt
inspection, as work in this area can’t continue until it
passes inspection. The building inspector returns for a
final inspection after the pipes are enclosed in the walls
and the plumbing fixtures are installed.
The design of the building and the choice of fixtures
affect the water and energy consumption over the
life of the building. The designer can encourage conservation
both by the selection of appropriate fixtures
and by increasing the user’s awareness of the amount of
water being used.
Visible consumption measures allow the user to see
how much water is being used, and to modify use patterns
for better conservation. Rainwater storage tanks
with visible water level indicators outside the bathroom
window show how much water is used in each flush.
Slightly undersized pipes allow users to hear the water
flowing. This is especially useful for outdoor taps, where
water may be left on.
LAVATORIES AND SINKS
Despite the hundreds of lavatory designs available in
the interior design market, few consider the way our
bodies work and the way we wash. Lavatories (bathroom
sinks) are designed as collection bowls for water, but we
use them for washing our hands, faces, and teeth quickly
with running water. Because of the design of the spout,
you usually have to bend at the waist and splash water
upwards to wash your face. Most lavatory fittings dump
running water directly down the drain. They are hard to
drink from and almost impossible to use for hair washing.
Most handles are hand-operated, as the name implies,
and you have to move your hands out of the water
stream to turn them on and off. Foot-operated controls
solve this problem. The sink and adjacent counter area
are often difficult to keep clean and dry.
For cleanliness and durability, lavatories must be
made of hard, smooth, scrubable materials like porcelain,
stainless steel, or resin-based solid surfacing materials.
Look for faucet designs that are washerless,
drip-free, and splash free, and made of noncorrosive
materials. Models are available that have permanent lubrication,
easy-to-change flow control cartridges, and
controlled compression to eliminate over-tightening
and wear on seals. Check for fixed faucet handle travel
and features that make servicing easy.
Faucets that comply with the American with Disabilities
Act (ADA) come in a variety of spout heights,
and feature single-lever, easy-to-grab models, wing handles,
and 4- and 5-in. blade handle designs.
Public restroom lavatories should have self-closing
faucets that save water and water-heating energy. Faucet
flow should be limited to a maximum of 1.9 liters
(0.5 gallons) per minute. Low-flow faucets that use 1.89
to 9.46 liters (0.5–2.5 gallons) per minute employ aerators,
flow restrictors, and mixing valves, which control
temperatures. They function as well as or better than
the 15- to 19-liter (4–5-gallon) per minute standard
faucets. Low-flow aerators save up to half the amount
of water used.
The term “sink” is reserved for service sinks, utility
sinks, kitchen sinks, and laundry basins. Utility sinks are
made of vitreous china, enameled cast iron, or enameled
steel. Kitchen sinks are made of enameled cast iron,
enameled steel, or stainless steel. The building code requires
sinks in some locations, and local health departments
may set additional requirements. Kitchen or
bar sinks in break rooms and utility sinks for building
maintenance are often installed even when not required
by code. Kitchen sinks are limited to a maximum flow
of 11.4 liters (3 gallons) per minute. Foot-operated
faucets free the hands, a great convenience and water
saver at kitchen sinks. The ADA sets standards for accessible
kitchen sinks, including a maximum depth of
15 cm (6 in.). Service sinks, also called slop sinks, are
located in janitor’s rooms for filling buckets, cleaning
mops, and other maintenance tasks. Wash fountains are
communal hand-washing facilities sometimes found in
industrial facilities.
Lavatories and other plumbing fixtures should have
an air gap, a clear vertical distance between the spout of
the faucet or other outlet of the supply pipe and the
flood level of the receptacle. The flood level is the level
at which water would overflow the rim of the plumbing
fixture. Bathroom sinks have overflow ports that
drain excess water before it can reach the end of the
faucet. Air gaps are required to prevent the siphoning
of used or contaminated water from the plumbing fixture
into a pipe supplying potable water as a result of
negative pressure in a pipe. Even if the water pressure
fails, there is no chance of contaminated water being
drawn into pipes as fresh water is drained back away
from the fixture.
BATHTUBS
The Saturday night bath was an American institution
well into the twentieth century. Bathing vessels were
portable and sometimes combined with other furniture.
A sofa might sit over a tub, or a metal tub would fold
up inside a tall wooden cabinet. Homes had a bath place
rather than a bathroom, and the bath and the water
closet were not necessarily near each other.
Modern bathing is done on a very personal scale,
in private, although tubs for two are currently in style.
Social bathing is limited to recreation, not cleansing, in
swimming pools, bathhouses, and hot tubs with spouts,
jets, and cascades.
Standing water is good for wetting, soaping, and
scrubbing, but running water is better for rinsing. We use
tubs primarily for whole-body cleansing, and also for relaxing
and soaking muscles. We follow a sequence of
wetting our bodies, soaping ourselves, and scrubbing—
all of which can be done well with standing water. Then
we rinse, preferably in running water. Tubs work well in
the wetting through scrubbing phase, but leave us trying
to rinse soap off while sitting in soapy, dirty water. This
is particularly difficult when washing hair.
Moderately priced all-in-one shower/bath enclosures
in acrylic or fiberglass are very common. Fiberglass is the
most cost effective, but acrylic has more durability and
luster. Showers and tubs are often installed as separate
entities, sometimes separated by a half wall or a door.
Tubs are often uncomfortable and dangerous for
people to get into and out of. The design of the tub
should ideally support the back, with a contoured surface
and braces for the feet. A seat allows most of the
body to be out of the water, and makes it easier to enter
and leave the tub safely. A hand-held shower is very
helpful for rinsing body and hair. Bathtubs are made of
vitreous china, enameled cast iron, or enameled steel.
Old-fashioned cast-iron claw-foot tubs are still
available. Thermaformed acrylic tub liners that can be
installed over existing fixtures are a fast and economical
way to upgrade a bathroom. Tubs are available with
integral skirts for easy installation and removable panels
for access.
For high-end designs, deeper than normal tubs
made of cultured marble, fiberglass, cast iron, or acrylic
may include whirlpools. Air tubs have a champagne
bubble–type effect, while river jets simulate the undulating
motion of white water river flow. Underwater
lights, vanity mirrors, and wall-mounted CD/stereo systems
with remote control are other luxurious options.
Some tubs have built-in handrails and seats, while others
have integrated shower or steam towers.
Clients may request big, two-person tubs with
whirlpools, but often they don’t use them as much as
they think they will. Whirlpool baths are available in
a great variety of shapes, including corner tubs 150 by
150 cm (60 by 60 in.) with built-in television monitors.
Consider 183 by 107 cm (72 by 42 in.) a maximum
practical size. As people become more conscious
of water use, they don’t necessarily want to fill up a
1136-liter (300-gallon) tub.
For safety’s sake, all tubs should have integral braced
grab bars horizontally and vertically at appropriate
heights, and no unsafe towel or soap dishes that look
like grab bars. Manufacturers offer very stylish grab bars
that avoid an institutional look. Tubs should be well lit,
and have easily cleaned but nonslip floors.
A shower pan that converts a standard 152-cm
(60-in.) tub to a shower without moving the plumbing
can improve safety. In this process, the old tub is removed
and replaced with a slip-resistant shower pan.
An acrylic wall surround can cover up old tile and unsightly
construction work.
A single-lever faucet offers two advantages. First, the
lever is easier to manipulate than round handles for
those who do not have full use of their hands. Second,
both temperature and flow rate can be adjusted with a
single motion. To protect children and people with disabilities
who have limited skin sensation, scald-proof
thermostatically controlled or pressure-balanced valves
should be used to control the flow of hot water.
Where a bathtub is required to be accessible, the
ADA specifies the clear floor space in front of the tub,
a secure seat within the tub, the location of controls
and grab bars, the type of tub enclosure, and fixed/
hand-held convertible shower sprays. One of the best
tub seats extends from outside the tub into the head of
the tub, allowing a person to maneuver outside the tub
before sliding in.
SHOWERS
Showers are seen as a quick, no-nonsense way to clean
your whole body. They waste lots of fresh running water
while we soap and scrub, but do an excellent job rinsing
skin and hair. With luck, you get a nice invigorating
massage on your back, but a real soak is impossible.
If you drop the soap, you may slip and fall retrieving
it. It is safer to sit when scrubbing, especially the legs
and feet, so an integral seat is a good idea.
Some showerheads encourage water waste. A flow
of 23 liters (6 gallons) per minute is typical, and as
much as 45 liters (12 gallons) per minute was once common,
using 22 liters (60 gallons) for a five-minute
shower. Most codes require limited showerhead flow,
with 9.5 liters (2.5 gallons) per minute being common.
These low-flow showerheads can be designed in new
showers or retrofitted, and save up to 70 percent when
compared with standard models. Smaller pipes and
heads increase the pressure, to give a satisfying shower
with less water. The cost of installing low-flow faucets
or showerheads results in savings of water, lower water
bills, and energy savings for hot water. Domestic hot
water accounts for 40 percent of U.S. energy use. An extra
minute in the shower puts another 0.23 kg of carbon dioxide in the air.
When helping children bathe, you should be able
to reach the controls from the outside without wetting
your arm. Even with soap in your eyes, you should be
able to manipulate controls from inside without seeing
them. Adjustable handheld shower wall bars allow each
person to adjust the showerhead to the perfect height.
Shower controls and heads are available grouped together
into a cleanly designed panel. Some showers feature
multiple shower sprays and a steam generator. Systems
that allow the sprays to be moved accommodate
people of different sizes, and some systems come with
programmable showerheads.
Where there is more than one shower in a public
facility, the ADA requires that at least one must be accessible.
There are two types of accessible showers: transfer
showers and roll-in showers. Accessible showers have
specified sizes, seats, grab bars, controls, curb heights,
shower enclosures, and shower spray units. How the
bather with disabilities will enter the shower is an important
design issue, particularly if a person is in a
wheelchair. For the bather who can physically transfer
from a wheelchair to a shower seat, the seat and grab
bars must be positioned to facilitate that entry. For those
who must shower in a wheelchair, the threshold cannot
be more than 25 mm high to permit roll in, and
the shower floor must be sloped to contain the water.
Moderately priced shower stalls are made of fiberglass
or acrylic. More upscale options include marble
and other stones, larger sized ceramic tile with borders,
glass block, and solid surfacing materials. Pre-plumbed,
all-in-one shower enclosures that include a steam generator
are also available. Shower pans are typically made
of terrazzo or enameled steel and are available in solid
surfacing materials as well. Barrier-free shower pans are
available. Grab bars, seats, anti-scald valves, nonslip
bases, and adjustable shower arms all add to safety.
Different kinds of shower seats are available—
adjustable, fold-up, and stationary. Regardless of type,
the seat must be installed where it will allow a seated
bather to reach the showerhead, valves, and soap caddie.
An adjustable showerhead can be hand-held by a
seated bather or bracket-held by a standing bather.
Grab bars, positioned to help the bather enter and
exit the shower, cannot extend more than 38 mm
(1.5 in.) from the wall; this is to prevent a hand or arm
getting caught between bar and wall. Walls behind the
seat and grab bars must be reinforced to support up to
114 kg (250 lb). This is done by installing 2 4 or
2 8 blocks horizontally between framing joists.
Controls should be installed above the grab bar.
Shower enclosures are usually enameled steel, stainless
steel, ceramic tile, or fiberglass. Frames for shower
doors come in a variety of finishes. The handle that
comes with the door can be upgraded to match the bathroom
decor. Etched glass doors add a design element to
the bathroom. Glass panel anti-derailing mechanisms
add to safety. Open, walk-in styles of showers with no
doors are also an option.
Heavy glass frameless enclosures that can be joined
with clear silicone are available up to 13 mm
thick, although the thinner 10 mm is usually adequate.
Body sprays with lots of jets pounding right at
a frameless door will inevitably leak, so pointing them
against a solid wall may be a better option. A vinyl gasket
can deter leaks, but may defeat the visual effect of
the frameless glass, and is unlikely to be effective for
very long. Totally frameless enclosures always lose a certain
degree of water, and glass doors generally don’t
keep steam in and don’t retain the heat as well as framed
doors. Complete water tightness may encourage mildew
growth, so a vented transom above the door may be
necessary.
Prefabricated modular acrylic steam rooms are
available in a variety of sizes that can comfortably fit
from two to eleven people. They include seating and
low-voltage lighting. An average steam bath consumes
less than one gallon of water. Steam generators are usually
located in a cabinet adjacent to the shower enclosure,
but may be located up to 6 meters (20 ft) away.
Look for equipment with minimal temperature variations,
an even flow of steam, quiet operation, and steam
heads that are cool enough to touch. Plumbing and electrical
connections are similar to those of a common residential
water heater. Controls can be mounted inside
or outside the steam room.
Modular saunas combine wood and glass in sizes
from 122 _ 122 cm (4 _ 4 ft) to 366 _ 366 cm (12 _
12 ft). There are even portable and personal saunas that
can be assembled in minutes. Heating units are made
of rust-resistant materials and hold rocks in direct contact
with the heating elements. Models are available in
cedar, redwood, hemlock, and aspen.
Showers may be required by code in assembly occupancies
such as gyms and health clubs, and in manufacturing
plants, warehouses, foundries, and other
buildings where employees are exposed to excessive heat
or skin contamination. The codes specify the type of
shower pan and drain required.
There are alternatives to our typical showers and
tubs. Traditional Japanese baths (Fig. 13-1) have two
phases. You wet, soap, and scrub yourself on a little stool
over a drain, rinse with warm water from a small bucket,
then (freshly cleansed) you soak in a warm tub. An updated
version uses a whirlpool hot tub for the soak. Locate
the hot tub in a small bathhouse with a secluded
view, and you approach heaven.
TOILETS, URINALS,AND BIDETS
In 1596, Queen Elizabeth had a toilet installed by Sir
John Harrington, who came from Bath, giving us two
euphemisms still in use today. A high water tower was
located on top of the main unit, with a hand-operated
tap for water flow to the tank, and a valve that released
sewage to a nearby cesspool. Harrington’s toilet was connected
directly to the cesspool, with only a loose trapdoor
in between. The queen complained about cesspool
fumes in this toilet without a trap. The new toilet fell
into disuse because Sir John wrote an earthy, humorous
book about it, which angered the queen.
British watchmaker and mathematician Alexander
Cummings put a backwards curve into the soil pipe directly
underneath the toilet bowl in 1775, which retained
water and cut off the smell from below. Cumming’s
patent application for a “stink trap” introduced
the trap that has been used on all subsequent designs.
What most of us call a toilet is technically called a
water closet. Toilets are not usually designed to facilitate
proper washing while eliminating. A toilet seat that
provides a cleansing spray is available from several
American manufacturers for use on existing toilets.
Bidets, which are popular in Europe and less often seen
in the United States, are designed for personal cleansing.
Toilets are available without a separate toilet seat,
with a warmer for the seat, and with warm water within
the toilet for washing.
Water closets, urinals, and bidets are made of vitreous
china. Toilet bowls could never be leak proof and
free of contamination until all the metal and moving
parts were eliminated. In 1885, an English potter named
Thomas Twyford succeeded in building the first one-piece
earthenware toilet that stood on its own pedestal base.
Porcelain toilets will not accumulate bacteria-harboring
scratches when cleaned. His toilet design is essentially the
same as the one used in the modern bathroom.
The height of the conventional toilet seat is a compromise.
A lower toilet seat is healthier for the average
person, as it approximates a squatting position, but is
more difficult for standing male use, and for some elderly
people or people with some disabilities. Higher
toilets provide more support. Toilets are often used as
chairs in the bathroom, and low ones are not at a comfortable
chair height. The standard toilet is somewhere
in between the lower and higher limits. Toilet manufacturers
offer toilets with seats at the same height as a
standard chair seat, marketed as comfortable for people
of all ages and statures. The recommended height for
a toilet that is accessible for people with disabilities is
457 mm (18 in.). Toilets are available at this height, or
an existing toilet can be retrofitted with special thick
seats or with a spacer ring placed between the toilet rim
and a standard seat. In addition, a grab bar next to the
toilet will help the user get up and down. Urinals for
use by men in wheelchairs are either wall mounted at
lower heights, or floor mounted.
Water closets and urinals can’t be designed to have
the type of air gaps found in lavatories. For example,
water closets and urinals in public buildings have a supply
pipe connected directly to the rim. Consequently, it
is a legal requirement in most areas that at each fixture
where a connection between the supply and waste
plumbing is possible, a vacuum breaker must be installed
on the supply line. When the pressure fails, air
is allowed to enter the line, destroying the siphon action
and preventing contaminated water from being
sucked into the system. You may have noticed the
chrome plated flush valve on every public toilet fixture;
this contains the vacuum breaker. Vacuum breakers are
also manufactured for outdoor faucets, where the end
of a hose may be left in a swimming pool or garbage
pail full of water.
Most codes require that all water closets specified
for public use have elongated bowls and seats with open
fronts. Specific clearances are required on each side and
in front of the bowl. Automatic flushing controls add
to the toilet’s accessibility and keep toilets clean. They
work by radiant heat from body pressure or by reflecting
a light off the user and back to the control. Toilets
designed for handicapped accessibility are usually wallhung
and have elongated fronts.
The ADA doesn’t apply to private residences, but
many designers incorporate the principles of universal
design to accommodate present or future needs of their
clients. The Federal Housing Act (FHA) applies to multiple
unit housing built with government funds, and
may require partial or full accessibility or provisions for
easy conversion of some units. Structural reinforcement
for future grab bars and wall-mounted water closets may
be required, and is a good idea anyway.
Toilet Plumbing
Our modern toilet (water closet) emerged in the 1940s
with tanks that hold about 19 liters (5 gallons) of water
mounted on the backs of the bowls. When you trip the
handle on the toilet, a flapper valve opens in the bottom
of the tank, releasing the water to flush waste away
and rinse the bowl clean. A portion of the water flows
out around the top rim, swirling to wash down the sides
of the bowl (Fig. 13-2). Most of the water flows rapidly
through a hole near the bowl bottom and propels waste
out through the drain trap.
The volume of water needed to do a thorough job
determines the size of the tank, so some tanks are bigger
than others, depending on the bowl design. Once
the tank empties, the flapper valve falls closed, and the
tank and bowl refill from the household water supply.
Water closets have large traps that are forced to
siphon rapidly during the flushing process and are refilled
with fresh water to retain the seal. The water closet
must be vented nearby to prevent accidental siphoning
between flushes. The small supply piping available in
houses can’t provide the quick, ample rush of water necessary
to operate a toilet’s siphon trap. Instead, water is
slowly collected in a tank at the back of the fixture. In
public buildings with frequent flushing of toilets, slowfilling
tanks could not keep up with the demand. Consequently,
commercial toilet installations use larger supply
pipes with special valves to regulate the strength and
duration of each flush.
Toilets That Conserve Water
Approximately 70 percent of the water flushed down
traditional-sized toilets isn’t required for effective
sewage transport. If a toilet predates 1985, it probably
uses between 19 liters and 28 liters (5–7.5 gallons) per
flush. The older the toilet, the more water it probably
uses. Studies performed in Massachusetts show that in
an average 3.2 person household where each person
flushes four times a day, the 27 liters (7 gallons) per
flush toilet uses 123,770 liters (32,700 gallons) of water
a year. Even a 13-liter (3.5-gallon) toilet reduces water
use per household to 62,074 liters (16,400 gallons) per
year. Studies done at various places around the country
show that toilets account for anywhere from 35 to 42
percent of all indoor household water use.
Low-consumption toilets lower building water use
by 30 to 40 percent. This reduces the load on municipal
sewer systems and saves fresh water supplies. Beginning
in 1994, it became illegal to make or sell in the
United States any toilet that uses more than 6 liters (1.6
gallons) per flush. These toilets became the center of
controversy when the law got ahead of technology, resulting
in steep price increases, problems with performance,
and unhappy consumers. Once they decided to
take a serious look at water consumption levels and
water conservation, fixture manufacturers responded
with only slight modifications in the basic product design.
The flush valve on existing water closets was shut
off prematurely, and less water was used with minimum
changes to the china fixture. What resulted has contributed
more to the negative impressions about 1.6 gpf
(gallons per flush) low-consumption toilets than any
other factor. Repeated flushing was often necessary to
clean the bowl after use.
Even so, two 6-liter flushes still use less water than
the former 13 liters (3.4 gallons) per flush, and most
times only one flush is actually needed. Over time, manufacturers
found ways to increase the swirling effect of
the water and clean the bowl better. To achieve lowconsumption
gravity performance, the size of the trap
and other openings were decreased. This resulted in a
stronger siphoning action to withdraw the waste, and
much improved performance. Still, there was double
flushing going on, and modifications continued to be
made to enlarge the trapway and water surface areas.
Although no longer legal for new installations in
the United States, many older, higher consumption toilets
are still in place in existing buildings. Older styles
include two-piece, lower pressure models, shallow trap
models, and one-piece styles that eliminate the seams
between the tank and the toilet. The mechanical systems
range from flush-valve commercial toilets to wash down
toilets, siphon jets, siphon vortex toilets, and blowout
toilets. These styles range between 9.5 liters (2.5 gallons)
and 30 liters (8 gallons) per flush. Toilet dams installed
in toilet tanks limit the amount of water used in
existing toilets.
Watersaver toilets use 6.4 liters to 13.2 liters
(1.7–3.5 gallons) of water per flush, which may not be
enough of a water savings to meet strict U.S. requirements.
They use a conventional flushing action, but save
water by employing higher water pressure and better
bowl shapes, better methods of filling and emptying,
and improved trap configurations.
Some toilets conserve water by offering variable
flushing controls. Dual cycle controls allow you to
choose how much water you need, as do vertical flush
sleeve valves. Pressure-reducing valves save water coming
in on supply lines.
There are two types of ultra-low-flow (ULF) toilets
currently available to homeowners that meet the legal
requirements: the gravity ULF and pressurized ULF.
Gravity ULF toilets have steeper-sided bowls to increase
the flushing velocity. The tanks are taller and slimmer
than older models, raising the water higher and increasing
the flushing power. These taller tanks also hold
more than 6 liters (1.6 gallons) of water, but the flush
valves don’t release it all, harnessing only the force of
the topmost 1.6 gallons. The tank never empties its entire
capacity, and it’s a clever way to increase flushing
power.
Pressurized ULF toilets look conventional from the
outside but use a unique air-assisted flush mechanism
inside the tank. The pressure-assist vessel inside the toilet’s
tank traps air, and as it fills with water, it uses the
water supply line to compress the trapped air inside. The
compressed air is what forces the water into the bowl,
so instead of the pulling or siphon action of a gravityfed
toilet, the pressure-assist unit pushes waste out. This
vigorous but somewhat noisy flushing action cleans the
bowl better than gravity units.
Pressure-assist flushing systems (Fig. 13-3) reduce
water use by elimination of leakage and double flushing.
The U.S. Department of Housing and Urban Development
(HUD) has calculated that a fixture can leak
up to 95 liters (25 gallons) per day, depending on the
age of the parts inside, but the pressure-assist unit holds
the water within the tank, eliminating leaks. A larger
water surface keeps the bowl cleaner, and a larger trapway
and fewer bends eliminate stoppages. Because the
water is contained inside the vessel within the tank, condensation
doesn’t form on the toilet tank. Fewer moving
parts reduce maintenance.
Pressure-assist toilets install in the same space as
conventional toilets, and require 138 kPa (20 pounds
per square inch, psi) of water pressure, which is typical
in residential housing. Pressure-assist toilets are used in
homes, hotels, dormitories, and light commercial applications,
and are available in handicapped accessible
models. More and more states are mandating the use of
pressure technology in commercial structures, primarily
to prevent blockages.
In 1986, a severe drought brought the water supplies
of San Simeon, California, to a severe crisis level at the
same time that the wastewater treatment plant demand
was reaching full capacity during the peak use season.
The choices were rather grim: new, supplemental water
sources, additional waste treatment capacity, or more rationing
that would close some of the motel rooms that
the city depended on for income. The alternative on
which the city finally settled was replacing all toilets with
low-consumption pressure assisted types, which reduced
water consumption in the town by 39 percent compared
to the older 3.5-gpf toilets. As a bonus, bowl stoppages
were almost completely eliminated.
With a central compressed-air system, very low water
consumption can be achieved. The Microphor flush toilet
has a design with two chambers for a flush that uses
only 1.4 liters (1.5 quarts) per flush. In the Envirovac
system, a vacuum is used to provide a 1.4-liter flush. This
system can be used in basements, as the sewer line may
run horizontally or even vertically.
Some toilets use a mechanical seal rather than a
water trap, and use only about 5 percent of the usual
amount of water. Chemical toilets use even less.
An alternative type of toilet is made by Incinolet.
Figure 13-3 Pressure-assist toilet tank.
Available as a toilet or a urinal, it has no plumbing connections
and reduces waste to a small volume of ash.
It requires connection to electric power and a 10-cm
(4-in.) diameter vent to the outside.
Composting toilets, sometimes called biological
toilets, dry toilets, and waterless toilets contain and control
the composting of excrement and toilet paper by
aerobic bacteria and fungi. Aerobic digestion generally
produces much less odor than anaerobic processes. The
composting process transforms the nutrients in human
excrement into forms that can be used as a soil conditioner.
Composting toilets can be installed where a
leaching field or septic tank, with their inherent problems
and expenses, are undesirable or impractical, including
areas that have placed limits on new septic systems,
and in parks and nature sanctuaries.
All composting toilets require a continuous supply
of room air drawn into the composting chamber and
vented out through the roof to provide oxygen for the
aerobic microorganisms that digest the wastes. Composting
toilets eliminate or greatly reduce water for
flushing but increase energy consumption, although the
amount needed to run a fan and keep the compost from
freezing is small, and is often supplied by a solar panel
on the roof. Grates, screens, electric fans, and ventilation
chimneys can provide ventilation. Airtight lids on
the toilet, screens over vents, proper maintenance, and
keeping kitchen scraps from the composting toilet will
deter unwanted insects. Some government agencies require
a permit before installing a composting toilet.
Urinals
Urinals reduce contamination from water closet seats
and require only 46 cm (18 in.) of width along the wall.
Urinals are not required by code in every occupancy
type. They are usually substituted for one or more of the
required water closets. Many bars and restaurants install
urinals in addition to the number of required toilets
to accommodate large crowds. The wall-hung type (Fig.
13-4) stays cleaner than the stall type, but tends to be
too high for young boys and for men in wheelchairs.
Where urinals are provided, the ADA Accessibility Guidelines
(ADAAG) requires that a minimum of one of them
comply with access requirements: a stall-type urinal or
a wall-hung fixture with an elongated rim at a specified
maximum height above the floor. Clear front space must
be allowed for a front approach.
Although uncommon, urinals can be built into residential
walls for pullout use, where they might be a solution
to the eternal male/female toilet seat dilemma.
Waterless urinals use a floating layer of a special biodegradable
and long-lasting liquid that serves as a barrier
to sewer vapors in the trap while still allowing urine
to pass.
PLUMBING CONSIDERATIONS
FOR APPLIANCES
Although such appliances as dishwashers and clothes
washers are not usually considered to be plumbing fixtures,
we are including them here as an aid to interior
designers, who frequently assist clients in selecting
them, and who locate them on their plans. We also discuss
appliances under the section on electricity.
A conventional dishwasher uses 45 to 68 liters
(12–18 gallons) of water per cycle, much of it heated
beyond the 49°C (120°F) household hot water supply.
Optional shorter cycles use around 26 liters (7 gallons).
Washing machines use 151 liters to 208 liters
(40–55 gallons) per full-size load cycle. Older-style
washers with “suds savers” allowed soapy, hot wash
water to be reused. Newer models have wider water
quantity and temperature selections, saving water and
energy. Front-loading machines greatly reduce the quantity
of hot water used per wash cycle. They also give you
cleaner clothes with less detergent and less energy than
agitator-type machines, and reduce wear and damage to
clothes.
Dishwashers and clothes washers have relatively
simple plumbing requirements. Be sure to leave adequate
space for access, especially in front of front-loading
machines. Both dishwashers and clothes washers use
vacuum breakers to prevent clean and dirty water from
mixing. Kitchens need regular water supply lines for the
sink and dishwasher, and waste lines for the sink,
garbage disposal, and dishwasher.
FIXTURE LAYOUT AND
INSTALLATION
As with other plumbing, fixtures should never be installed
in exterior walls where there is any chance of below-
freezing weather. Small-scale fixture plumbing will
fit into a 15-cm (6-in.) interior partition, but wall-hung
fixtures require chases 46 to 61 cm (18–24 in.) thick.
Plumbing chases are required where there are more than
two or three fixtures. Plastic pipes are not allowed in
residences in many jurisdictions.
Fixtures should be located back-to-back and one
above the other wherever possible for economical installation.
This allows piping space to be conserved and
permits greater flexibility in the relocation of other partitions
during remodeling. Wherever possible, locate all
fixtures in a room along the same wall.
Bathroom fixtures should be located with space
around the fixture for easy cleaning and for access for
repair and part replacement. Faucets and toilet valves
are subject to constant repairs, and drains must be kept
free of obstructions. Waste piping clogs with hair, paper,
cooking fats, and tree roots. When water supply piping
fills with mineral scale, it must be replaced, which
is something to be checked when the bathroom is undergoing
a major renovation. Access panels may be required
in the walls of rooms behind tubs, showers, and
lavatories. Trenches with access plates may be required
for access to pipes in concrete floors. Water heaters are
especially prone to scale from mineral-rich water, and
their electrical or fuel-burning components need periodic
attention.
Prefabricated bathrooms are available, with manufactured
assemblies of piping and fixtures. One-piece
bathrooms have no seams between the fixtures and the
floors. Fixture replacement is difficult and expensive,
and access for plumbing repairs must be provided
through adjacent rooms.
Some types of occupancies present special plumbing
design challenges. Plumbing fixtures for schools
should be chosen for durability and ease of maintenance.
Resilient materials like stainless steel, chromeplated
cast brass, precast stone or terrazzo, or high-impact
fiberglass are appropriate choices. Controls must be
designed to withstand abuse, and fixtures must be securely
tied into the building’s structure with concealed
mounting hardware designed to resist exceptional forces.
Prisons employ extreme measures to prevent plumbing
fixtures from becoming weapons. Heavy-gauge stainless
steel fixtures with nonremovable fittings are very expensive
and require tamper-proof installation.
COMPRESSED AIR
AND VACUUM LINES
In some urban locations, vacuum lines, compressed air
lines, or high-pressure water mains for driving tools
were once run below streets as utility systems. Today,
gas, electric, and steam are the only energy utilities in
common use. An electric-powered compressor in some buildings
furnishes compressed air, which is supplied through
pipelines for use in workshops and factories. Compressed
air is used to power portable tools, clamping
devices, and paint sprayers. Air-powered tools tend to
be cheaper, lighter, and more rugged than electrical
tools. Vacuum lines are installed in scientific laboratory
buildings.
The design of bathrooms and public restrooms involves
not only the plumbing system, but also the mechanical
and electrical systems. There are special space planning
considerations in bathroom design as well, which have
an impact on the plumbing layout.
DESIGNING PRIVATE
BATHROOMS
The minimum code requirements for a residence include
one kitchen sink, one water closet, one lavatory,
one bathtub or shower unit, and one washing machine
hookup. In a duplex, both units may share a single
washing machine hookup. Each water closet and bathtub
or shower must be installed in a room offering privacy.
Some jurisdictions require additional plumbing
fixtures based on the number of bedrooms. Many
homes have more than one bathroom. Here are some
guides to terminology and to area requirements.
The basic three-fixture bathroom with lavatory, toilet,
and combination tub/shower is designed for one
user at a time. You should allow a minimum of 3.25
square meters (35 square ft), although elegant master
baths may be much larger. A compartmented bathroom
has the lavatory in a hallway, bedroom, or small alcove,
with the toilet and bath in a separate space close by. The
toilet can also be separate, with its own lavatory. Compartmented
bathrooms are very convenient for couples
or multiple children using the components simultaneously.
They are often found in hotels. A guest bath generally
includes a lavatory, toilet, and shower stall, rather
than a full bathtub. You should allow a minimum of 3
square meters (30 square ft). The term half-bath refers
to a lavatory and toilet, and uses about 2.3 square meters
(25 square ft). The classic powder room under the
stairs is a half-bath. If located near the mudroom entrance,
they work very well for kids playing outdoors,
allowing a quick visit without tracking dirt through the
house.
Bathrooms are often the victims of the one-size-fitsall
philosophy. Pullout step stools help children at lavatories.
Counters and mirrors at varying heights for seated
and shorter people help accommodate everyone.
Within such a usually limited space, storage can become
a major problem. Families often buy toilet paper
and other supplies in bulk, and need storage for at least
some of these supplies within the room and the rest
nearby. Towels should be stored within the room. Multiple
users can leave a plethora of toiletries and grooming
supplies on counters and shelves, and building in
