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8 Answers

Double-brick house in Toronto - how to deal with high indoor humidity after insulating?


First time posting, but I have learned tons from reading many of the excellent articles and postings on this site.

Here's our situation. We live in a double-brick one and a half story house in Toronto that was built in 1949. We have done a number of energy efficient upgrades and are now experiencing consistently high indoor humidity (60%+) which leads me to believe that we have a ventilation problem.

The upgrades we have done:

In General questions | Asked By Leif Schumacher | Oct 10 12
3 Answers

In terms of passive house, Pretty Good House, or net zero energy house construction, how much should be budgeted for control systems that monitor and control humidity, CO2, exhaust, etc.?

I am asking because I've been advised that although a tight house may require smaller sized HVAC equipment, the high efficiency equipment are more expensive and there are expensive control systems not present in conventional house construction.

In Green building techniques | Asked By Lecole Vielle | Nov 18 13
1 Answer

Using Durock and Thinset/Mortar

Not sure if it's just my head. Ready to do the Durock while it's the right temp out before it gets too cold and I have to run the furnace without attic insulation. I have a couple questions that I can't seem to get the answers to:

I have a standard, unmodified Mapei Mortar for laying the durock with. The directions on the bag state not to tape the seams with this product. Not sure why and now what do I use to set the seams with or what kind of mortar will work?

And should I tape and mud the seams now or wait til I'm ready to put my tile in a few weeks down the road?

In General questions | Asked By Geoffrey Cook | Nov 17 13
1 Answer

Masonry Renovation Window Replacement Details

What is the best way or multiple ways to install a highly efficient (low air and energy loss) window detail for installing new custom vinyl windows in a masonry opening? Including backer rod, sealant choices, tapes, etc

In General questions | Asked By Jim Gramata | Nov 17 13
1 Answer

How do you connect the old and the new stucco when patching?

How to you connect the old and the new stucco wall? In the beginning there was a leak due to a crack on the corner side on a stucco wall as we opened it, and opened an area approximately 8.0'' x 3.0'' wide as the projected size to be cut. Now, my question: what is the proper procedure including the material to be used, do you need caulking materials to connect its border between the old and the new stucco? How do you repair the stucco which separates the window glass and the stucco wall, and the existing expansion joints and the new stucco?.

In General questions | Asked By Zosimo Largo | Nov 17 13
6 Answers

Exterior Foam Board in CZ4

I am building a house in KY and I am getting conflicting information from insulation contractors and I was hoping to get some feedback here.

In Energy efficiency and durability | Asked By Will Norris | Sep 28 12
6 Answers

Ice & Water Shield when there's no ice?

I live in zone 4C in Portland Oregon (and at low elevation) where ice damming is, as far as I can tell, a non-issue. We get maybe one light snow per year, and only brief periods of freezing (maybe a few days at most?). I've only been here 8 years but I don't recall ever seeing a single icicle.

Does it still make sense to have I&W shield installed at the eaves, perhaps in case of gutter backup? Is it a good idea in valleys, simply to mitigate risk from heavy rains? Or is it basically pointless?

The roof is 6/12, simple gable with one small hip sticking out perpendicular ("L" shape).

In Energy efficiency and durability | Asked By Nick Welch | Nov 14 13
6 Answers

2 by 8 stud walls

I am getting resistance to building 2 by 6 walls with 4 inches of exterior foam.The builders in my area...Peterborough ,Ontario... say it is too much labor to be cost effective and the build outs to accomodate the windows and doors take them out of their comfort zone .My question is ...can I effectively use a 2 by 8 for exterior stud wall and 2 inches of foam to get the r value I desire ...they use Bibs to insulate ....thanks,Bob

In Energy efficiency and durability | Asked By bob holodinsky | Nov 15 13
1 Answer

What is the difference between heating with a geothermal furnace vs a regular boiler that pulls from a well?

The water is being pulled from deep in the ground then heated by gas to heat the water in the tubes. How would the Geothermal work if I still have to heat water that is pulled from deep in the ground now?

In General questions | Asked By Shelly Gladwwell | Nov 16 13
2 Answers

Resistance to Closed Crawl Space in Zone 4C

Our house project in Zone 4C is nearing the point where we are going to sign a contract. I am planning the equivalent of a Pretty Good House: 60-40-20-10, with a closed crawl space. In our county, radon mitigation is required. After soliciting foundation and framing bids, the developer is giving me resistance on this. He has written to me, saying this:

In General questions | Asked By Gordon Taylor | Nov 15 13
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