When planning a new
layout for a bathroom, several factors have to be taken into account. Specific
codes exist that regulate the placement of fixtures such as toilets, bathtubs,
or sinks in the bathroom. These guidelines exist to ensure that the finished
bathroom is both practically designed as well as safe. It is also important to
know what categories bathroom layouts fall into. Below you will find
information on the codes and regulations for different fixtures as well as
categories of bathroom layouts.
Toilets
- No other fixture is
allowed to be within 15 inches of either side of the toilet’s middle point.
- The space between a
toilet and the fixture next to it must be at least 4 inches.
- There must be at least
24 inches of uninterrupted space in front of the toilet, and at least 36 inches
between the toilet and the opposite wall.
*An exception to this rule: the path
of an opening door may swing through the 24-inch space in front of the toilet.
- When separating the
toilet from the rest of the bathroom, the enclosure must be at least 36 by 66
inches.
Sinks
- Sinks need a distance
of 15 inches from the midpoint to a wall.
- If two sinks are
installed, they must be at least 30 inches from the each other’s centerline.
- There must be at least
2 inches between a sink and another fixture.
- A sink cannot be placed
on an opposing wall from a toilet unless there is at least 36 inches between
the two fixtures. This does not apply if existing fixtures from an old bathroom
are being replaced.
Showers
- Showers need at least
24 inches from the entrance of the shower to the nearest wall or fixture.
*30
inches is recommended for easier access.
- The shower stall itself
must have an area of at least 34 by 34 inches, however at least 36 by 36 is
recommended.
Bathtubs
- Bathtubs need at least
21 inches from the open side of the tub to a wall or fixture.
*30
inches is recommended for easier access.
- Most bathtubs are about
60 inches long by 32 inches wide, but can be as large as 72 inches by 48
inches.
- A corner bathtub is
around 60 inches by 60 inches on average.
BATHROOM DESIGN TERMINOLOGY
- Half bathroom consists of only a toilet and
sink.
- Three quarters bathroom
consists of a toilet, sink and shower, but does not have a bathtub.
- Full bathroom has a
toilet, sink and combination bathtub/shower.
- One and a half bathroom
has a toilet, sink, bathtub, and shower fixtures.
*Shower and bath fixtures are
separate in this design
OTHER SPECIFICATIONS
Drainage & Vent Pipes
Drainage and ventilation
pipes can be made out of PVC or ABS pipes. This is usually a matter of
contractor preference. While PVC has a higher level of heat resistance from
sunlight than ABS does, the ABS has a wider range of chemical resistance than
PVC.
- Toilets need at least a
2- or 3-inch wide drainage pipe.
- As most toilet drains
are at the 12-inch mark, drainage pipe should be installed 12 inches from the
finished wall. (Roughly 13 inches from drywall.)
- Toilets need at least
2-inches of ventilation pipe.
- Sinks require a 2-inch wide
or larger drain that will intersect with a 3-inch wide horizontal run.
- Sink drains should be
installed at least 19 inches above the floor to be compatible with standard
sink height.
- Sink vent pipes should
be at least 2 inches in diameter.
- Bathtubs and showers
require at least a 2-inch wide drain that intersects with a 3-inch wide horizontal
run.
- The main stack is the
central pipe all drain pipes connect to. These should be at least 3 inches in
diameter.
Supply Pipes
Older supply lines may
have been made from copper so if you find yourself replacing existing fixtures
it may be required to purchase copper parts. If installing a new bathroom
entirely, current commonly used parts are made from PEX pipe.
- Bathtub/shower supply
lines are usually 1/2-inch to 3/4-inch in diameter, depending on the valve.
- Sinks and toilets tend
to have a standard 1/2-inch diameter pipe.
- If installing a stub
out for a sink, it should be 19 inches above the floor. If there are two sinks,
the stub outs need to be at least 8-10 inches apart.
- If installing a stub
out for a toilet, it should be at least 8 inches above the floor.
Tub and Shower Fittings
- Tub controls should be
at least 26-28 inches above the floor.
- The tub spout should be
at least 6-8 inches above the top edge of the tub.
- The shower head should
be at least 74-76 inches above the floor.
- The flow/temperature
control for the shower needs to be at least 46-48 inches above the floor.
CONCLUSION
It is important to
remember that the figures above are general guidelines, but do not apply in all
situations. It would be wise to research local plumbing codes for specific
regulations on distances. Whether you are remodeling an old bathroom or
designing a new one, it is important to be economical with the space available.
It is equally important to find a balance between functionality and convenience,
while adhering to local regulations.
