Replies

1. 
   Chris Laumer-Giddens | Nov 15, 2010 11:42am | #1

   Thanks Martin!

2. 
   Riversong | Nov 15, 2010 01:34pm | #2

   It looks like the Riverdale house suffers from one of the primary problems with double stud walls: extension of the floor decks through the thermal envelope to the exterior, thereby creating repetitive on-center thermal bridging.

   It also uses moisture-vulnerable OSB and an interior poly vapor barrier which most cellulose manufacturers warn against (and will void the warranty on one).

   I thought we learned those lessons in the 80s and moved beyond them (except for the preponderance of OSB, which came later).

   I've designed several double-wall homes that don't suffer from those deficiencies - it's not difficult to do.

3. GBA Editor
   Martin Holladay | Jan 23, 2011 06:32am | #3

   For those who have been following the Riverdale project in Edmonton, Alberta, here's a January 21, 2011 update received in an e-mail from Peter Amerongen:

   "Our Riverdale project seems to be using more heating energy than predicted. Early measurements from both Mill Creek and Belgravia seem to be showing higher than H2K predicted heating energy. I don't know where the short fall is. It could be lower passive solar gains is certainly using more heating energy than predicted. It could be lower internal gains than predicted, lower HRV efficiency or just higher heat transmission losses. We need to find out what we can do better. It may be that HOT2000 is over predicting passive solar gains or under predicting heating energy in super insulated houses. It is also possible that we aren't rigorous enough with our inputs."