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2 Answers

Any issues with using rigid foam board as in fill in exterior walls.

200+ year old colonial I am residing from the exterior. Removing everything so I am looking at the back of the horse hair plaster. Could dense pak cellulose or have open or closed cell foam sprayed in from the exterior. The problem is timing. I will be working on this a couple days at a time stripping and sheathing. I have three sides to do and I don't want to coordinate with an installer four or five times to come out when I am ready. So my thought was to use rigid foam (its post and beam) cut roughly to size and spray foam around the edges to seal it in place. Then fill the bay this way.

In General questions | Asked By terry grube | Jul 5 12
3 Answers

Attic insulation

I have 20 year old home in SC that has fiberglass batts between ceiling joists and a few years ago I had blown fiber (12 inches) on top of that. However the area over the attached garage has never been insulated at all. Since we are having record heat I've decided to insulate the garage area since yesterday it was over 100 degrees in the garage. I am not sure that I am getting full benefit out of the
existing insulation due to pot lites and perhaps the soffit vents may be blocked or partially blocked.

In Energy efficiency and durability | Asked By Jerrry Harris | Jul 3 12
6 Answers

Double stud walls & wood shrinkage

My evolving plan for my new house in northern Michigan uses double stud walls. The outer wall sits on the concrete basement walls while the inner wall sits on the floor that sits on an inner stud wall in the basement. The inner stud wall of the basement is separated from the concrete by 3" of XPS. The outer stud wall supports the roof trusses. The inner main floor stud wall is sheathed on it's exterior side and this sheathing is the vertical portion of the primary air barrier. The outer stud wall supports the roof trusses.

In Energy efficiency and durability | Asked By Jerry Liebler | Jul 3 12
1 Answer

Insulating floor of addition

We are adding a 2nd story addition to the back of our house in Portland, Oregon. The addition is supported on columns so the first story is open creating a covered porch. I am trying to decide how to insulate the floor since it is open to below and will have plumbing in the floor.

My thought was to use R-30 unfaced fiberglass batts in the floor, a layer of 2" XPS fastened to the bottom of the floor joists, 2x4 flat sleepers, and then 1x6 T&G.

In Building Code Questions | Asked By David Fischer | Jul 4 12
11 Answers

Most energy-efficient ERV?

I'm planning a net-zero energy home built from SIPs, and am trying to size my PV system accordingly. Unfortunately, I'm finding that the ERV that the home needs eats electrons with relish (one model, if run at the highest setting, will consume about 6 kWh per day if it runs continuously). That said, I don't understand the workings of an ERV to know if it does run continuously or cycles, or what the average daily electricity consumption is. I'm hoping folks on this forum can share their insights.

In Mechanicals | Asked By Claire Anderson | Sep 16 09
9 Answers

Condensation Problem

I decided to liven up this gloomy winter day in the Mid-South, by posting about a problem I recently encountered. I am just posting the information pertaining to the problem and will not add my two cents about the possible solution until we see what others think about this. Pictures are attached.


In General questions | Asked By Grant Dorris | Jan 13 11
1 Answer

Lingering Odor after using 0 VOC Paint

I live in Zone 4C near Seattle.

I painted a bedroom with Benjamin Moore Natura 0 VOC Paint about 35 days ago. I painted two coats of a green color waiting the required time between coats. It was the first time I had used this paint. My wife and I didn't like the color so two days later I repainted it white, again waiting the required time between coats.

In Green products and materials | Asked By Kevin Larsson | Jul 3 12
8 Answers

How to ventilate a hip roof

We are going to be replacing the roof on our house as part of a project to make the house more energy efficient as well as an addition and remodel. I live in NJ - a little bit north of central, so we have pretty good swings in climate between summer and winter. The house has a shallow hip roof, and the house is 42' wide and 26' deep. There are nice large overhangs at the eaves, and we will be putting in lots of venting there, but the question is what to do at the top. There is an old existing power fan, two passive vents and a ridge vent.

In Energy efficiency and durability | Asked By Eric Lavitsky | Jun 27 12
6 Answers

Air-Entrained Concrete Walls?

Has anyone used air-entrained concrete for foundation walls in a cold climate? I don't mean the "Krete" products. The reported R-values are R-3.9 as opposed to regular concretes R-0.08. For an 8" wall you are going to get somewhere around R-30? From reading around a bit it seems you can get a 20mpa (3000#) air entrained concrete mix with 6% air. I wonder what the extra cost would be...would it be worth it from an insulation perspective?


In Energy efficiency and durability | Asked By Tim Shepp | Jul 2 12
7 Answers

I have a friend who is remodeling his attic in Columbia, SC and his builder is telling him that all he needs for insulation

is 5.5 inches ofopen cell spray foam and that this will perform at R49. Of course his existing rafters happen to 2x6s. I recomende furring down and blow in netted cellulose or R30C. Any comments

In Energy efficiency and durability | Asked By Kevin Brady | Jul 2 12
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