Just wanted to know what it meant:13R Residential Occupancies up to and including Four Stories in Height? What happens when you want to go above Four stories like a hotel that want to use CPVC pipe.
If it is a hotel of four or more stories, NFPA-13 would apply. The rooms would be light hazard, mechanical rooms, storage rooms, kitchens, etc. would be considered ordinary hazard group I. As far as using cpvc pipe it would be acceptable as long as it meet the AHJ's approval, plans and specifications, and NFPA-13. I have used it many times in this type of situation. Some of the places that the cpvc can not be used would be in exposed areas, stand pipes in the stair wells, on a dry system in attic if required.
Get a copy of cpvc catalogs, they have some very good information concerning installation.
Check the listings on the CPVC now. I believe you can install it exposed in Light Hazard areas when using QR sprinklers. There are actually quite a few new listings for CPVC piping in sprinkler systems.