Solid ABS ASTM D-2661 for use above the roofline for DWV vents?

[TheOverThinker]

In my area I can only find ASTM F-628 Foam core pipe, not ASTM D-2661 solid ABS pipe.

Given that, what material can I use for roof penetrations, that will hold up in the sun? I see a lot of roofs with ASTM F-628 foam core pipe vents, where after a few years the vent look chalky and sun damaged. Copper and galvanized of course last a long time. Are there any of the plastics that will be suitable for reasonable roof lifetime? I prefer something that does not depend on paint for UV protection.

 

[James Henry]

In my area I can only find ASTM F-628 Foam core pipe, not ASTM D-2661 solid ABS pipe.

Given that, what material can I use for roof penetrations, that will hold up in the sun? I see a lot of roofs with ASTM F-628 foam core pipe vents, where after a few years the vent look chalky and sun damaged. Copper and galvanized of course last a long time. Are there any of the plastics that will be suitable for reasonable roof lifetime? I prefer something that does not depend on paint for UV protection.[/QUO

Are there any of the plastics that will be suitable for reasonable roof lifetime?

There are no plastics that can withstand the elements for without degradation. I would fabricate the last 16" of the horizontal vent, including the angled fitting and the 3' section of vent that penetrates the roof out of cast iron. you can couple the cast iron and PVC together with a shielded no-hub band. as far as the code for height tie down recommendation, you'll have to look that up for your location.

 

[Sponsor]

 

[Reach4]

Lead roof boot is the most stable. Put a plastic pipe up, put the lead roof boot over the pipe, as you would put a shingle, fold the top of the roof boot over and into the pipe.

It can probably also be used for other types of roof, such as rock and tar. I don't know how it would work with terracotta tile or standing seam.

Edit: PVC plumbing pipe has both solid (ok for pressure) and foamcore (DWV) versions. However PVC should be protected from the sun with paint or other.

PVC electrical conduit has a sun inhibitor. I think it is solid. Two-inch schedule 40 is widely available, if that is the size you are using. Three inch and bigger is not that hard to find. https://www.menards.com/main/electrical/conduit-conduit-fittings-raceways/conduit/pvc-conduit/3652640/p-1444427697666.htm You could glue that into ABS fittings with green transition cement if your local code permits.

 

[James Henry]

There are no plastics that can withstand the elements for without degradation. I would fabricate the last 16" of the horizontal vent, including the angled fitting and the 3' section of vent that penetrates the roof out of cast iron. you can couple the cast iron and PVC together with a shielded no-hub band. as far as the code for height tie down recommendation, you'll have to look that up for your location.

I was posting a suggestion from both of your threads at once.

 

[Plumber69]

Just use cell core, if you are worried paint it black

 

[TheOverThinker]

Consider http://www.sdplastics.com/ultravioletresistance.html

 

[TheOverThinker]

Ok, I'll go with cellular core, but I'm going to cut off the flange from an old fitting,
and glue it on top. That way the weak cellular core material is not exposed to free-thaw.
The fittings are still made from solid ABS plastic.