C402.2.6 Insulation of radiant heating systems.Radiant heating system panels, and their associated components that are installed in interior or exterior assemblies shall be insulated to an R-value of not less than R-3.5 on all surfaces not facing the space being heated. Radiant heating system panels that are installed in the building thermal envelope shall be separated from the exterior of the building or unconditioned or exempt spaces by not less than the R-value of insulation installed in the opaque assembly in which they are installed or the assembly shall comply with Section C402.1.4.
EXCEPTION: | Heated slabs on grade insulated in accordance with Section C402.2.4. |
[Statutory Authority: RCW
19.27A.020,
19.27A.025,
19.27A.160 and chapters
19.27A and
19.27 RCW. WSR 22-14-091, 23-12-101, and 23-20-021, § 51-11C-40226, filed 7/1/22, 6/7/23, and 9/25/23, effective 3/15/24. Statutory Authority: RCW
19.27A.025,
19.27A.160, and
19.27.074. WSR 16-03-072, § 51-11C-40226, filed 1/19/16, effective 7/1/16. Statutory Authority: RCW
19.27A.020,
19.27A.025 and chapters
19.27 and
34.05 RCW. WSR 13-04-056, § 51-11C-40226, filed 2/1/13, effective 7/1/13.]