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27 Answers

As an energy adviser in Manitoba, I see a lot of basements with cast-in-place joists. If the header space is filled with concrete up to the underside of the floor deck, the advice is easy: Cut R-5 XPS to fit, caulk or foam it in, and glue the vapour barrier.

While I'm at it - how about the rim joist space parallel to the joists?

In Energy efficiency and durability | Asked By Geoff Ireland | Dec 10 11
15 Answers

I looked at a house today that has a couple of wood-burning fireplaces. They are back to back in separate rooms. One of them has metal-framed glass doors that are tight fitting but not gasketed; the other has mesh curtains. They both have old-school metal dampers right above the firebox, the type where you can reach in, grab a short metal arm, and open or close the damper by engaging notches in the arm on a pin. They both have small make-up air inlets in the firebox sides that are run to the exterior. They both have stubs for gas log lighters.

In Mechanicals | Asked By David Meiland | Jan 7 11
9 Answers

Hi. I own a bungalow in Minneapolis, MN built 1921 with a poured concrete foundation. I am finishing 1/2 of this basement as a legal bedroom, and wish to put in drywall walls and ceiling. My wife and I have lived here for seven years, and have had nary a drop of water leak through the foundation and into our basement. No mold or mildew problems, either, though it can get humid down there in the warmer months, for which we use a dehumidifier.

In General questions | Asked By Jesse P | Feb 25 11
24 Answers

Hello

In General questions | Asked By Ali Good | Apr 25 10
5 Answers

I live in Anchorage, Alaska (zone 7) in a early 70's split entry home. The original construction consists of 2 x 4 walls, but an addition to the house 2 years ago was built with 2 x 6 walls.

In Energy efficiency and durability | Asked By jon kunesh | Dec 7 11
40 Answers

There’s a lot of talk about the benefits of exterior insulation, but also the downsides of rigid foam materials—that is, the chemicals involved, future disposal issues, wrong-side vapor barriers, susceptibility to fire and pests. It is possible to use rockwool / mineral wool as an alternative, but this is not often discussed or practiced, at least in this country. That may be largely due to the lack of compressive strength of rockwool compared to foam boards, requiring some strategy to support the cladding other than simply driving screws through the insulation.

In Green building techniques | Asked By Thomas Jefferson | Oct 24 10
17 Answers

Green roofs: raise your hand if you've done `em. I want to talk about absolute-minimal approach.

I'm about to get one set up on this outbuilding, and on reviewing the necessary layers, I'm wondering if I can strip the layers down to as few as possible.

Generally, the layers necessary are:
waterproofing layer
root barrier
insulation
drainage
growing medium
plants

Since we will probably be installing by putting trays of sedum in lightweight growing medium down, here's what I see:

In General questions | Asked By Minneapolis Disaster, 6B | Nov 16 11
3 Answers

In planning the construction of my house I may have some of those "obvious in hindsight" questions. When the exterior foam insulation begins to exceed the depth of a standard receptacle or lighting fixture box, how do you support them? Obviously you want to minimize the amount of insulation removed so providing solid blocking all the way back to the wall is out. I am picturing long screws through the back of the box and foam to solid blocking, with plastic spacing tubes around them to prevent crushing the foam due to fixture/receptacle movement.

In Green building techniques | Asked By Nathan Spriegel | Dec 9 11
21 Answers

I live in Alberta, Canada (great white north). I built a new house myself and wanted extra insulation. I purchased 1" styrofoam that has foil on both side which passes as a vapour barrier (P2000 is the manufacturer).

In Energy efficiency and durability | Asked By Adam Willert | Jun 11 10
3 Answers

Schematic diagrams demonstrating the use of rigid foam insulation under slab on grade frost wall foundations always show the rigid foam under the slab and less frequently under the footer or on the external surface of the stem wall. If the goal is to have an optimal thermal break barrier under this type of foundation construction why not place the foam both under the slab and completely around both sides of the stem wall and under the footer? It seems to me that this is the only way to create a complete thermal break for the foundation.

In Green building techniques | Asked By Tim Ward | Dec 8 11
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