Monday, March 17, 2014

An Air Sealer's Work is Never Done

Well, we are back at it - working on the house again.

No, we do not have our construction loan yet.

Yes, the house is gradually nearing completion.

Yes, this drives me crazy. But we do have assurances that the construction loan will go through. Our contractor is willing to go ahead and get back on the house despite not having the actual loan yet. Thank you, Randy.

Anyway, so I am trying to get to some additional air sealing details. These photos show the water supply Pex tubing in the kitchen which runs from the mechanical room under the floor to the kitchen. In other words, this tubing bridges the thermal envelope. The plumbers sealed it with the orange foam in a can. You can see that the Pex tubing is not completely sealed to this extreme air sealer's standards. The orange foam doesn't cover the entire side. In addition if the tubing moves as in the 3rd photo, it opens up and fails to maintain the seal with the tubing.

So what does a good Air Sealing Specialist do? The choice is tapes or flexible sealants. For this area I choose tapes to make a good seal with the tubing.

I used Pro Clima Unitape with a flexible hole in the center to run the pipes through. 

Then I reinforced the seal with one of my favorite tapes - Pro Clima's Tescon Vana.  Love this stuff. I also use it on holes in my work jeans. 

For the vent pipe, I went with Siga Wigluv tape. 
One area I have to air seal and I don't really know how is around the electrical boxes.

It's not really needed because the boxes are in a space in front of the insulation layer and do not penetrate the thermal envelope. (Remember the thermal envelope on this house is sealed at 3 levels - taped on the exterior,  taped and caulked on the inside every single stud bay, then the dense pack cellulose was blown into the stud bay covered with a completely air sealed vapor permeable membrane, Intello Plus. I still like the idea of having redundant layers of air sealing layers so I do want to seal around the boxes. Not to mention that the inspector said we have to because that is where the thermal envelope is usually sealed and that is what they expect. But I don't really know how to do this. More internet study.

We are getting ready to tile the mechanical room because we need it so we can have some heat. We've chosen a wood look tile from Home Depot that is only $2.39 sq. ft. John really likes it. 

I'm going to install it over Schluter Ditra membrane to uncouple the tile from the floor to help prevent cracking. I figure in the laundry room I need to do that.

Well, that's sort of where we are now. Lots more going on - 4 inch red oak floors have already been  installed, doors will probably be installed tomorrow, followed by window trim. So we are getting somewhere. I'll try to keep you better informed the last half of this month.