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4 Answers

Airtight sliding doors?

Hi All,

Does anyone out there know of manufacturers of very airtight (ie, passivehouse level, or close) sliding glass doors? And maybe - though this is a long shot - also Dade county (hurricane) compliant?


In Green products and materials | Asked By Cramer Silkworth | Dec 12 11
27 Answers

What to do when the ends of the floor joists are embedded in concrete?

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

If you're gonna have a fireplace....

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

Finishing a room in basement with sketchy poured concrete foundation and related questions...

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

Excessive Frost on Windows


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

REMOTE wall retrofit - the next steps have me puzzled

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

Alternative (Non-Foam) Outsulation Strategy Using Rockwool

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

disassembling the green roof Dagwood sandwich

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
growing medium

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

Penetrations in deep exterior foam

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

Not sure if my vapour barrier is done right or in the right spot. Can you tell me what is right?

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
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