Putting on new roof (with new plywood sheathing) on mid-70's 2-story house. We're in unincorporated King County WA, 502 ft above sea level. Septic system pumped regularly. Surrounded by cedars, so often get large branches whacking on roof. Squirrels, raccoons, etc. at times.
Would like to improve, or better, eliminate, 2 existing roof plumbing vents on front roof (esthetics, occasional heavy snow load, and previous leak issues). I assume the 2 vents are for the ground floor sink/toilet and the 2nd floor sink/toilet/bathtub, which are vertically one above the other. Toilets are Totos installed by Love Plumbing 3-4 years ago.
Have recently read about Air Admittance Valves (eg Studor, Oatey). We would leave other bathroom roof vents (at least one, as I believe is required) in place. Assuming that AAVs are ok by code, would appreciate some advice on the following:
1. how would a plumber verify that the 2 bathrooms on the front of the house are using the 2 existing front roof vents and that one or both could be "converted" to using AAVs? Aside from diagramming the visible fixtures and connections, would the plumber need to look into the attic? If so, just a pop head and good light through access door or would they need to crawl into attic? It's fairly low slope and not easy to access.
2. Understood about the possibility of needing access panels cut into walls for bath or toilets.
3. What happens to the "old" stack pipe, does it need to be removed completely or can it just be "capped" below and left in place running up into the attic but cut off and capped below the roof deck?
4. All work would be done by a licensed plumber. Does this kind of work require an inspection?
5. How much work is involved, assuming things go well, i.e. one visit to determine work, second visit to complete? The reason I ask is that we need to coordinate with roofing progress to avoid having open penetration. The existing roof is very fragile, so we can't have anybody up there to remove vents or cover them over prior to the new roof being started, but if we need Co. inspection then that will complicate the timing.
I hope the following picture will help explain. Thank you for your comments.
Would like to improve, or better, eliminate, 2 existing roof plumbing vents on front roof (esthetics, occasional heavy snow load, and previous leak issues). I assume the 2 vents are for the ground floor sink/toilet and the 2nd floor sink/toilet/bathtub, which are vertically one above the other. Toilets are Totos installed by Love Plumbing 3-4 years ago.
Have recently read about Air Admittance Valves (eg Studor, Oatey). We would leave other bathroom roof vents (at least one, as I believe is required) in place. Assuming that AAVs are ok by code, would appreciate some advice on the following:
1. how would a plumber verify that the 2 bathrooms on the front of the house are using the 2 existing front roof vents and that one or both could be "converted" to using AAVs? Aside from diagramming the visible fixtures and connections, would the plumber need to look into the attic? If so, just a pop head and good light through access door or would they need to crawl into attic? It's fairly low slope and not easy to access.
2. Understood about the possibility of needing access panels cut into walls for bath or toilets.
3. What happens to the "old" stack pipe, does it need to be removed completely or can it just be "capped" below and left in place running up into the attic but cut off and capped below the roof deck?
4. All work would be done by a licensed plumber. Does this kind of work require an inspection?
5. How much work is involved, assuming things go well, i.e. one visit to determine work, second visit to complete? The reason I ask is that we need to coordinate with roofing progress to avoid having open penetration. The existing roof is very fragile, so we can't have anybody up there to remove vents or cover them over prior to the new roof being started, but if we need Co. inspection then that will complicate the timing.
I hope the following picture will help explain. Thank you for your comments.
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