of the floor joists. The face-to-face measure-
ment for the vertical length of 3⁄4″ pipe can
be made by first securing a length of the
appropriate diameter pipe to the underside of
the floor joists. Depending on the direction that
the floor joists run, either the 1⁄2″ pipe to hose
bibb B or the 3⁄4″ pipe to the water heater must
be fastened to the lower edge of the floor joists.
The other pipe is run in the space between two
floor joists. If the horizontal 3⁄4″ pipe to the water
heater runs below the floor joists, a 3⁄4 × 1⁄2 × 3⁄4
reducing tee should be installed at the end
of the vertical 3⁄4″ pipe. If the 3⁄4″ horizontal pipe
to the water heater runs between two joists, a
350
Section 3 Plumbing System Design and Installation
Figure 20-2. A whole house water filter is installed in the pipe run from the water meter. If unfiltered water is
acceptable for hose bibbs, a branch pipe can be run to the hose bibbs before the water enters the filter.
Below floor joist
to hose bibb B
Between floor joist
to water heater
Building
water
service
90° ell
3⁄4″ × 3⁄4″ × 1⁄2″
Reducing tee
3⁄4″
3⁄4″
1⁄2″
90° ell
Union
MIPT
adapter
Water
filter
MIPT
adapter
Union
MIPT adapter
Ball valve
Meter
yoke
Meter stop
Water
meter
3⁄4″
1⁄2″
Between floor joist
to hose bibb B
Below floor joist
to water heater
3⁄4″
Alternate Layout
1⁄2″ 90° ell
1⁄2″
3⁄4″ × 1⁄2″ × 3⁄4″
Reducing tee