I had to enforce one the other day that made sense but it was a little late because the old option has worked for 30 years that I know of ;
Inspected a slab Friday that had a 4 inch PVC pipe ran in the slab . Code now calls for metal incased in concrete. The metal will rust out but the concrete will be there.
PVC has worked for 30 years of my knowledge but is not rated for heat.
This only got addressed after many questioned whose job it was to install : Heat and air or the plumber . It was neither . It now belongs to the plumber as the codes have addressed it. Before it took no license to install, as many carps did it because the trades fought over it here .
Now we address the electrician to run the hose above fart fans above insulation height. He says its the H@A guys job !
Tim Mooney
Replies
I had a client tell me the same thing. However, I found this recently on the IRC web site.
IRC Section G2437 (Clothes Dryer Exhaust) is amended by adding section G2437.5.3 to read as follows:
"G2437.5.3 Under slab installation. Exhaust ducts for domestic clothes dryers shall be permitted to be constructed of schedule 40 PVC pipe provided that the installation complies with all of the following:
1. The duct shall be installed under a concrete slab poured on grade.
2. The underfloor trench in which the duct is installed shall be completely backfilled with sand or gravel.
3. The PVC duct shall extend not greater than one (1) inch above the interior concrete floor surface.
4. The joints of the PVC duct shall be solvent cemented."
Interresting to say the least.
What I wrote was added to the Arkansas Plumbing Code .
Im not in the office , but at home , so I dont have reference here to print.
My problem with what the site says doesnt address somthing happening to the PVC such as a possible melt down. I know it shouldnt be an issue . The plumbing code does say the metal pipe shall be surrounded completly in concrete so that the concrete it self will act as the opening surrounding the metal pipe.
Tim Mooney