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3 Answers

How to insulate a cathedral ceiling?

I am planning a deep energy retrofit of my home. I am located in Calgary Alberta. Climate zone 3a. Average winter temperature in Dec and Jan is -14c (7 deg Fahrenheit). But it can get down to minus -50f, and -20f is not unusual for extend periods of time during the winter.

In Energy efficiency and durability | Asked By David Richardson | Jan 3 14
6 Answers

Correct basement slab poly install

Getting ready to start a new home and have a few questions about the basement slab. I understand I need the gravel put down first, then XPS, and then vapor barrier before the slab. I keep reading about many different kinds of poly to use as the vapor barrier. I have found this poly and was wondering if it will be suitable? It is Grip Rite 10 mil clear poly sheeting, and it is made from virgin resins. I have also read that it must be black colored poly under the slab. Does the color really make a difference? Thanks for any input/suggestions.

In Green building techniques | Asked By Morris Farris | Mar 16 14
4 Answers

Looking for free or cheap heat loss software

I am looking for a free simple heat loss program so I can play around with various wall, window, floor assemblies? Any ideas?

In General questions | Asked By kye ford | Mar 16 14
10 Answers

Which way does the air flow within the house?

Might be an odd question but I have been trying to understand this for the longest.

With all the windows closed in my single-story house + basement, how can I figure out the direction of natural air flow. I assumed that due to stack effect, I would be able to locate those positive & negative air pressure differences to identify air infiltration/exfiltration.

In General questions | Asked By Jeff Watson | Mar 13 14
4 Answers

Cold weather crawl space insulation

First time home owner- I am planning on installing insulation into a crawl space in an older home in the 5-A Western NY area. It has 3 vented access points to the outside, I placed a thick vapor barrier down and around pillars. There's no heat source except currently poor insulated pipes from the hot water furnace. (soon to be fully insulated). There's no insulation at all going up to the floor currently.

In General questions | Asked By Chris Perry | Mar 17 14
6 Answers

What causes this mildew?

I am trying to understand what is causing the "mildew" striations in the attached image. I am an architect in Southern Louisiana and saw this happening on a local building (not one of mine) and I am trying to understand what can cause this issue, so that I can prevent this on any of my projects. A little background about the picture. The building is in hot-humid climate in southern Louisiana. The picture is taken on the north/west facade. It is a church with a large interior volume.

In General questions | Asked By Scott Welty | Mar 17 14
0 Answers

Where to use Polyiso Rigid Foam Insulation Board

I just bought a home made of all cinder block. The previous owners covered the exterior of the house with Polyiso Rigid Foam Insulation Board and then cedar siding on top of that which i would like to remove and replace with stucco. Should i keep the insulation on the exterior of the house and stucco over it or should I remove the foam and stucco directly over the block?

In addition, I found a stack of about 20 - 2"sheets of the Polyiso foam board in my attic. Can i use these to insulate my basement or should I be using a XPS foam board?

Thanks for your help.

In Energy efficiency and durability | Asked By Dave Sacco | Mar 17 14
3 Answers

Exterior rigid foam insulation

I am well into a 2 year build of a cottage near Ottawa Canada which I believe makes it equivalent to zone 6. I say cottage, but I am trying to build to the standard of a house.

In Energy efficiency and durability | Asked By Mike 88 | Mar 17 14
3 Answers

Zone 3/Central GA 12x32 weekend cabin on 36" above grade piers

Building Envelope Critique Please/Materials purchased and we're about to begin:
1) From interior: 1x6 T&G pine fastened directly to 2x6 studs 24" OC; R-19 fiberglass batts/caulked gaps & seams; 1/2" plywood sheathing; one layer 1/2" pink foam board/taped seams; 4x8 exterior panels. Where is best positioning for my WeatherMate Plus wrap?

In Energy efficiency and durability | Asked By Brad Skeeters | Mar 14 14
4 Answers

What is the best insulation for an unfinished work/craft room in the basement?

I have a basement workroom that I'd like to expand to a craft room for our kids, but it's currently uninsulated poured concrete and freezing in the winter. I was hoping to slap up something like a rigid board insulation, that could be left uncovered, but it seems even polyisocyanurate needs a gypsum board layer.

In Green products and materials | Asked By Laura Braceland | Mar 16 14
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