My last post ended with a photo of some electrical conduit sticking out from a wall. My original plan for air sealing these types of penetrations was going to be to stretch a square of neoprene rubber around the conduit, then tape the neoprene to the plywood. Since this was the first piece of conduit to be installed, I let the neoprene sit around the conduit for a while before taping it down, to see what would happen - if anything...
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| That's about half an inch of conduit sticking out there. |
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| What happened was that after a while, the neoprene started failing. The white colour within the cracks is fibre reinforcement... I had thought that this stuff would hold up better- apparently not. Next at bat is EPDM. |
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| I happen to have plenty of this 45 mil EPDM leftover from roofing the sunroom. I cut the circle for the conduit to the size of its inside diameter - that way it stretches the EPDM slightly when it's fitted. Time will tell if it holds up better than the neoprene... I am confident that it will. |
Who - David Byrne and St. Vincent.
Hello Lucas,
ReplyDeleteIn my daydreaming about the elements of a tight house, I had wondered if similar wall penetrations could be sealed with Ice and Water membrane or the rubber which is used for commercial roofing. Had you considered these options?
Jim
Hi Jim,
DeleteYes,the EPDM I used for roofing the sunroom is commonly used for commercial roofing jobs.
I never considered ice and water shield...
I'm not sure it has the same stretchy durability that EPDM has...
For such wall penetrations, why not just use "touch n foam"?
ReplyDeleteHi Greg,
ReplyDeleteI prefer this approach because I'm not sure I trust foam to maintain the seal over the long term.