Air admit valve or exterior vent? Posted: Apr 26, 2007 12:17 PM Reply
Hi, the regs say I can fit an air admittance valve on the end of my soil stack vent. The soil pipe has an horizontal run inside the roof space of a ground floor extension. This would save be making a hole in the extension pitched roof for an exterior vent. This relieves negative pressure but not positive, so are there any big disadvantages to doing this? Thank you