Tuesday, April 19, 2011

Poly Vapour barrier passes! Really? But we're not perfect...

Wow~ another green sticker for passing the vapour barrier/insulation installation!  But I must admit, I'm a little surprised.  We have a bunch of gaps/holes in the vapour barrier and stuff we still need to fix. I found a bunch of places were we still need to use some [or a lot] of acoustical sealant to fix the vapour barrier to the wall. Or to something. And today, I spent some time taping up the slits the electrician made in the vapour hats of the pot lights in the attic. And I checked the loft floor windows. And I ran out of sticky tape. Doh!

Today, we had a couple of netzero home gurus drop by!  Peter Amerongen & Bob Heath dropped by to check out our progress. I wish they would have came by a month ago! I'm sure they could have talked me out of using sticky red tape and had all sorts of suggestions. Like how to use acoustic sealant around electrical outlet vapour hats without using a half a roll of tuck tape to ensure a good seal. And there was a discussion about polyurethane vs. epoxy on floors. And a very helpful tip not to put anything against the triple paned windows on a hot day, as Bob has shattered the middle glass pane because of the super heated air space causing too much pressure. Weird. But it was great to have them over to talk shop. And hope we can all learn much more from each other.


  1. Hello Shafraaz,

    Can you expand on the comments about Polyurethane vs epoxy? Would you also explain the warning about how items in contact with triple pane glass will cause overheating in the air space?

    Thanks Jim

  2. We were discussing /wondering if putting polyurethane down over the concrete floor would create "bubbles" where there are cracks and pits in the concrete like epoxy would.

    And apparently Bob experienced that his windows became extremely hot in between the air space of the middle glass pane and the inside glass pane in his triple glazed window. So hot, that the slightest pressure from the inside actually caused the middle pane to shatter. Thus, don't throw anything at the window or push on the window on a hot summer day... He warned that this was a condition of high heat gain windows in particular. I wonder if the glass panes were made too big for the frame?

  3. The problem occurs on cold, sunny days if an item is placed on the window ledge against the inner pane of the window unit. The item (in my case it was a down vest left by a contractor) traps heat against the inside surface of the inner pane while the outside surface of the inner pane is still cold. This temperature difference causes uneven expansion of the glass and causes it to crack.

    The problem with the middle pane was mechanical damage during shipment from Winnipeg. I found it remarkable that they could break the middle pane of a triple pane window without damaging either of the outer panes.


  4. Bob and Shafraaz, Thanks for the notes.
    When I was a kid living near Quebec City, the glass in our dryer cracked. The dryer sat in the basement near the back door. The technician said that the cold (-30 F) air dropped down. The temperature stresses between the inner and outer surfaces of the glass caused it to crack.
    Your window advice sounds similar. -Jim