User Guide

Plumbing Design Assistance Manual l Appendix E – Expansion arm and loop calculations l 139
Table E-1: PEX pipe expansion arm calculations ½" to 3"
2½" PEX pipe expansion arm
Delta
T (ΔT)
Run
(ft)
Delta L
(in)
Flexible arm
length (in)
L1
(in)
L2
(in)
PEX with PEX-a Pipe Support, strut and strut clamps has a thermal expansion rate of 0.08"/10°F ΔT/100 ft. (2.03mm/5.56°C ΔT/30.48m).
60
50 0.24 9.52 1.90 3.81
60 0.288 10.43 2.09 4.17
70 0.336 11.27 2.25 4.51
80 0.384 12.05 2.41 4.82
90 0.432 12.78 2.56 5.11
100 0.48 13.47 2.69 5.39
70
50 0.28 10.29 2.06 4.12
60 0.336 11.27 2.25 4.51
70 0.392 12.17 2.43 4.87
80 0.448 13.01 2.60 5.21
90 0.504 13.80 2.76 5.52
100 0.56 14.55 2.91 5.82
80
50 0.32 11.00 2.20 4.40
60 0.384 12.05 2.41 4.82
70 0.448 13.01 2.60 5.21
80 0.512 13.91 2.78 5.56
90 0.576 14.76 2.95 5.90
100 0.64 15.55 3.11 6.22
90
50 0.36 11.67 2.33 4.67
60 0.432 12.78 2.56 5.11
70 0.504 13.80 2.76 5.52
80 0.576 14.76 2.95 5.90
90 0.648 15.65 3.13 6.26
100 0.72 16.50 3.30 6.60
100
50 0.4 12.30 2.46 4.92
60 0.48 13.47 2.69 5.39
70 0.56 14.55 2.91 5.82
80 0.64 15.55 3.11 6.22
90 0.72 16.50 3.30 6.60
100 0.8 17.39 3.48 6.96
110
50 0.44 12.90 2.58 5.16
60 0.528 14.13 2.83 5.65
70 0.616 15.26 3.05 6.10
80 0.704 16.31 3.26 6.53
90 0.792 17.30 3.46 6.92
100 0.88 18.24 3.65 7.30
120
50 0.48 13.47 2.69 5.39
60 0.576 14.76 2.95 5.90
70 0.672 15.94 3.19 6.38
80 0.768 17.04 3.41 6.82
90 0.864 18.07 3.61 7.23
100 0.96 19.05 3.81 7.62
2½" PEX pipe expansion arm
Delta
T (ΔT)
Run
(ft)
Delta L
(in)
Flexible arm
length (in)
L1
(in)
L2
(in)
PEX with PEX-a Pipe Support, strut and strut clamps has a thermal expansion rate of 0.08"/10°F ΔT/100 ft. (2.03mm/5.56°C ΔT/30.48m).
130
50 0.52 14.02 2.80 5.61
60 0.624 15.36 3.07 6.14
70 0.728 16.59 3.32 6.64
80 0.832 17.73 3.55 7.09
90 0.936 18.81 3.76 7.52
100 1.04 19.83 3.97 7.93
140
50 0.56 14.55 2.91 5.82
60 0.672 15.94 3.19 6.38
70 0.784 17.21 3.44 6.89
80 0.896 18.40 3.68 7.36
90 1.008 19.52 3.90 7.81
100 1.12 20.58 4.12 8.23
150
50 0.6 15.06 3.01 6.02
60 0.72 16.50 3.30 6.60
70 0.84 17.82 3.56 7.13
80 0.96 19.05 3.81 7.62
90 1.08 20.20 4.04 8.08
100 1.2 21.30 4.26 8.52
160
50 0.64 15.55 3.11 6.22
60 0.768 17.04 3.41 6.82
70 0.896 18.40 3.68 7.36
80 1.024 19.67 3.93 7.87
90 1.152 20.87 4.17 8.35
100 1.28 22.00 4.40 8.80
3" PEX pipe expansion arm
Delta
T (ΔT)
Run
(ft)
Delta L
(in)
Flexible arm
length (in)
L1
(in)
L2
(in)
PEX with PEX-a Pipe Support, strut and strut clamps
10
50 0.04 4.24 0.85 1.70
60 0.048 4.65 0.93 1.86
70 0.056 5.02 1.00 2.01
80 0.064 5.37 1.07 2.15
90 0.072 5.69 1.14 2.28
100 0.08 6.00 1.20 2.40
20
50 0.08 6.00 1.20 2.40
60 0.096 6.57 1.31 2.63
70 0.112 7.10 1.42 2.84
80 0.128 7.59 1.52 3.04
90 0.144 8.05 1.61 3.22
100 0.16 8.49 1.70 3.39