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2 Answers

Should I ventilate my crawl space or seal my crawl space?

I live in the northern part of Utah about 50 miles south of the Idaho Utah border and it's fairly dry all year long except in the early spring months, and I'm not sure if I should ventilate my crawl space or seal it off. I have read several websites that tell me that ventilated crawl spaces in the dry states in the western US are okay to have, then I've had several websites tell me ventilating a crawl space is altogether bad no matter where you are. I would very much appreciate if somebody could help shed some light on this for me.

In General questions | Asked By Casey Mallory | Oct 24 12
2 Answers

Do ordinary curtains provide ANY energy/heat saving benefit?

Some years ago I read that "ordinary" curtains & miniblinds do not provide much in the way of energy/heat saving.

In Energy efficiency and durability | Asked By kathlene kelley | Jan 7 12
6 Answers

XPS below rafters in cathedral ceiling zone 4

We are finishing off some attic space (most over a garage, some over main part of house) for very occasional use as a guest bedroom, kid's playroom. Total sq ft is about 350, with cathedral ceiling (8 ft at the collar ties) with ridge vent and soffits. I'm fairly certain that the roof structure is just shingles, paper and plywood. Air vent baffles were installed between all 2 x6 rafters and OSB was used as backing behind the 5 ft knee walls (and was thoroughly air sealed).

In General questions | Asked By Rob Silbajoris | Oct 17 12
3 Answers

How to fill the smallest of cracks with foam or silicone

I'm trying to fill some small spaces in between 2 x 6 roof decking that sits on top of finished timber frame rafters at the point above the exterior wall. The deck boards for the finished ceiling inside are the same ones that continue to the outside where they become the finished soffit boards.
These boards are not tongue and groove and were freshly milled when installed. They have since shrunk and left gaps of 1/16 of an inch to a 1/4 inch allowing for outside air to pass through the gaps and into the interior loft space.

In Energy efficiency and durability | Asked By Dave Cummings | Oct 23 12
5 Answers

Rigid foam insulation Int/Ext & Condensation

I've heard a lot of varying opinions on sheet foam insulation and the topic of condensation. Just want to check that I'm choosing an appropriate method of insulating my home.

I will have 2" of rigid EPS foam insulation on the exterior attached to the outside of existing shiplap through to the studding. Over the foam I'll install building paper, then either Hardie Board or Stucco. On the inside of the home, there is some old kraft paper stapled to the shiplap. In the wall I'm installing 3" of rigid foam, then a vapor barrier sealed with acoustic seal.

In Energy efficiency and durability | Asked By Chris Cameron | Oct 19 12
6 Answers

Crawl Space

We're in the beginning stages of renovating and adding a second floor to a 1,200sf waterfront camp (zone 6A) that will become a "pretty good house", better than code and air tight as possible. The current crawl space is about 30" - 36" high and has a layer of 6mil poly with a thin layer of clean sand for ballast/protection and 8" CMU foundation and sump pump. There is evidence of water about 3" up the wall where the ground slopes (half the crawl space) which I'm told by locals happens when the lake floods on very rare occasions.

In Energy efficiency and durability | Asked By Gerry Smith | Oct 19 12
5 Answers

How can I best install rigid foam as I finish my attic?

Hi folks,

I'm finishing off my attic. The plan is to use fiberglass between the old true 2x6 rafters, which will be vented with baffles. I then want to put lots of rigid foam on top of the rafters, as I'm in a cold climate in upstate New York. I'm thinking 4 inches.

How can I find screws to long enough to fasten the furring strips through the foam to the rafters?

Will the foil-faced foam act as an adequate vapor-barrier as long as I seal the seams with aluminum tape?

Need I use any special drywall on top for adequate fire protection?


In Green building techniques | Asked By J Stair | Oct 19 12
27 Answers

Rainscreen Roof?

I've seen lots of info about rainscreen walls, what about roofs? I'm planing on using a standing seam metal roof, 10/12 pitch. Should I be considering rainscreen details for this?

In General questions | Asked By Eric Mikkelsen | Oct 13 12
3 Answers

What are the pros and cons of pouring concrete in an existing crawl space, and how thick should it be?

I admit I am a bit of neat freak, but the idea of have a nice concrete floor in the crawl space appeals to me.

This is a spacious crawl space: 20x24 feet and nearly 6 feet tall. It houses the propane furnace and the electric water heater.

The walls I believe are concrete black. The floor is currently stone and dirt above a white plastic sheet which shows through in a few places. The crawl space opens to a smaller basement below it.

I believe the crawl space s currently vented to the outside (a couple of small, probably ineffective vents), and I am also considering sealing it.

In Green building techniques | Asked By Moya Mim | Oct 18 12
4 Answers

Spray foam basement ceiling to block moisture and improve efficiency?

Upstate NY--The homeowner bought a home not realizing that it was in a flood plain. Over the last 5 years the basement and crawl space have flooded up to the rim twice, taking out the boiler and water heater, which have been moved upstairs. When it's not flooded, the basement + crawl have high moisture levels which is causing mold upstairs as well. We've been asked to fix moisture and improve efficiency. Ideally, we'd raise the building three feet, but the money isn't there.

Here's the question: can we spray foam the basement rim and ceiling and install an HRV upstairs?

In Energy efficiency and durability | Asked By Bennett Sandler | Oct 17 12
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