Lots and lots of Sprayfoam

Yesterday they started sprayfoaming our little laneway house.  Although sprayfoam is often used in certain applications as part of house construction, the unusual thing about this house is we are using a whopping 7.5" of closed-cell sprayfoam, installed on the outside of the building.  This acts as a big blanket that completely envelops the house.  Green Building Advisor calls sprayfoam the "King of Insulation".

First layer of closed-cell sprayfoam being installed.  All finished trim and windows have been masked-off to protect from over-spray.

Closed-cell foam has an R-value of 6 of 6.5 per inch.  This means the sprayfoam provides at least R45 on the outside of the house, plus it acts as our air barrier and vapour barriers.  

The closed-cell foam has to be built up in layers.  I looks like they can put on about 2" to 3" of foam each pass, so it will take them a few days to completely fill the 8" cavity.

Today while I was watching the contractor work (the job is so big the they actually using TWO sprayfoam rigs at the same time to do the job), I was thinking it seems a bit crazy to put on this much insulation because it is a lot of work (and cost).  But then I realized it is like pre-buying all of my fuel / energy now.  By superinsulating the house, I've built in keeping the house warm now, at the outset.  I won't have to buy a bunch of energy for the remainder of the life of the building because all of the insulation reduces the heating needs of this home by 90% over a conventional home.

The sprayfoam contractor is Energy North Construction and so far they seem to be doing a good job.  They've been pleasant to deal with, accommodating and responsive.  This job is unusual, but they were keen to tackle it.  

As bonus content, here is a little video of dancing sprayfoam guy: