Sealing Thermopex through the foundation

[DeerMeadowFarm]

I've finally made the leap to but an OWB. I dug my trenches this weekend and purchased my Thermopex. My buddy is an electrician and has a concrete core cuttting machine. My question is, how do you seal the Thermopex to the foundation? Aerosol foam? Silicone?

Thanks!

 

[DaveBP]

Bear in mind that ant and termites will interpret spray-can foam below the surface as a welcome mat and doorway.

 

[DeerMeadowFarm]

Bear in mind that ant and termites will interpret spray-can foam below the surface as a welcome mat and doorway.

OK....suggestions then?

 

[DaveBP]

The first thing that comes to my mind is the mastic modeling clay stuff that is used to seal around electric service cable entrances through wall and foundations. Weather proof and insect proof, I think. Duxseal is one brand name as I remember. Should be able to get that at any Lowesdepot. If you heat it up it gets pliable enough to caulk around the space between your pipe and wall. Tough to work with when it's cold.

I wouldn't count on it to mechanically hold the duct in place though. Clamp on the inside of the wall to be sure the thing is not pulled out of the wall from soil movement.

Don't know if it's the most appropriate material, I just happen to have a bog block of it I found at the dump.

 

[Frozen Canuck]

Foam would be preferred, just make sure to put a heavy coating of foundation mastic over the foam once it has cured to deter pests, Then repair the membrane on the foundation (if it has one), allow to cure then backfill

 

[mikefrommaine]

Hydraulic cement.

 

[goosegunner]

+1 on the hydraulic cement

 

[DeerMeadowFarm]

Great tips; thanks!

 

[flyingcow]

Hydraulic cement.

thats how my Thermopex was done. Looks good

 

[kabbott]

whenever I run pipes through foundations i use a PVC sleeve and hydraulic cement... then
use a fernco reducing coupling on the outside from the sleeve to the pipe, allows for some
flex and stays water/bug tight.