User Guide

Plumbing Design Assistance Manual l Chapter 6 – Installation methods l 79
Expansion-compensating devices
As a generally accepted practice, an
expansion-controlling device with xed anchor
points or a continuous run of PEX-a Pipe
Support with xed anchor points is installed
every 65 ft. of straight-length piping in a
domestic hot-water system. Always install the
device at the mid-point of two xed points (see
Figure 6-37).
Fixed anchor points
To account for expansion, use xed anchor
points to restrict piping movement. Ensure
xed anchor points are constructed with
materials that will provide rigidity to the support
system and use a pipe clamp that will restrain
the specic piping material.
When installing strut-type applications, Uponor
recommends using rubber-lined strut clamps to
aid in the restriction of movement.
Expansion arm
The exible arm should be long
enough to prevent damage; place
support clamps far enough from
the wall to allow for longitudinal
thermal expansion.
For a list of calculated
exible arm lengths, refer
to Appendix E.
Expansion loop
The same applies for an
expansion loop. However, the
arm length (LB) must be divided
into three sections.
For a list of calculated expansion
loop legs, refer to Appendix E.
Two hole open short angle
Steel strut
All-threaded rod
Two hole open short angle
Strut clamp
Uponor PEX pipe
Steel strut or other
approved device
Fixed anchor point
Fixed anchor point
LB
L ∆L
Fixed anchor point
Fixed anchor point
L2 L2
L1
L
∆L/2 ∆L/2
Figure 6-37: Fixed anchor point
Figure 6-38: Expansion arm
Figure 6-39: Expansion loop