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5 Answers

Adding thermal mass to an old wood-frame house

Hi. I'm wondering if there's a way to add thermal mass to the floors and internal walls of an old wood frame house without adding so much weight that it compromises the structure. Ideally, I'd like to add more low SHGC glass on the south side wall of a Southwest oriented bedroom, with sufficient overhang to block direct summer sun, but realize that doing so without adding sufficient thermal mass won't result in good heat capture in the Winter.

In Green building techniques | Asked By Noel Kalenian | Dec 3 12
11 Answers

Can Cardinal LoE 180 be applied to both surface #2 and #3 of an IGU ?

I want to install double glazed replacement windows that have high solar heat gain and a low u value. The Cardinal product for this purpose is LoE 180 applied to surface #3. I would like to have the 180 coating applied to both surface #3 and #2 to further decrease the U value but maintain the high solar heat gain attributes of the IGU. My local Marvin window distributor told me that Marvin told him that 180 could not be used on adjacent surfaces as I am requesting. I have not spoken directly to Cardinal about this.

In Energy efficiency and durability | Asked By Tim Ward | Dec 1 12
1 Answer

What is an energy-efficient refrigerator?

Looking for recommendations for an electric refrigerator to use in a solar-powered (photovoltaic system) house. Will also use a freezer as a separate appliance.

In Energy efficiency and durability | Asked By jula bunkham | Sep 9 12
3 Answers

Will I Have Moisture Problems?

I have learned a lot from this forum and have now started to have concerns regarding my home. Our 1900 sq ft ranch style home was built in 2006 and we had little-to-no awareness of the importance of energy-efficiency and green building. We live in a moderate climate, about 35 miles south of St. Louis, MO.

In Energy efficiency and durability | Asked By Ken French | Dec 1 12
2 Answers

Insulation for a cathedral ceiling

I'm working out the details for an addition I'll be building next summer. I'm in northern Minnesota. I'll have a cathedrial cieling at a 10/12 pitch and I'm planning on using 2x12 rafters wo have the room for insulation. The room is 29' wide the direction that the rafters run.
From what I've been reading I don't necissarily need to ventilate the roof as long as I make certain to seal the space very well. I have a couple ideas I'm looking at for that and I'm looking to see if either of my potential ideas have any red flags against them and perhaps pros and cons between them.

In Energy efficiency and durability | Asked By Mark Larson | Dec 2 12
2 Answers

Garage door detail on FPSF

Doing a FPSF w/ an attached garage(heated) in zone 5a. Does anybody have a good detail for an overhead garage door where it contacts the slab? Have a few ideas in mind, but need something that will last. That is one nasty thermal bridge to contend with....

In Green building techniques | Asked By Todd Kalin | Dec 2 12
1 Answer

NYSERDA is producing entertaining videos

Here's a NYSERDA video explaining "whole house" principles:

More videos here:

In Energy efficiency and durability | Asked By Martin Holladay | Dec 2 12
1 Answer

Insulating a barn ceiling

I live in northern New Jersey. I am insulating the room above my barn. The barn is unheated. I am planning to insulate the floor from underneath and cover it with plywood.

My question is whether to use faced or unfaced insulation and if faced is recommended, which way should the facing face?
Thank you

In Energy efficiency and durability | Asked By Randy Aubrecht | Dec 1 12
5 Answers

Air leakage or just interior humidity / stale air?

I have a 1930s home in Sudbury, 4 hours north of Toronto, Ontario. Temperatures get down to -40 degrees C in the winter here. The home is an old log home. 2 years ago, I installed 3" polyiso on the exterior of the house, and replaced the windows with Fibertec, triple glazed windows, high SHGC on south face, mid-low on remaining orientations. I also chose fixed windows for better peformance on north and south walls, as prevailing winds are east-west.

In Energy efficiency and durability | Asked By Aaron Dent | Dec 9 10
7 Answers

Ideal roof overhang length?

I think I have decided on the wall assembly that I want to use but by the sounds of it it spend time concentrating on the wall but very little time on the roof.

I have read several books on sustainable design and affordable or low tax housing. My general plan was to build a rectangular house with a gable end roof on a 4/12 pitch. I had intended to use either a 16” or 24” raised heel truss with 2’ overhangs. I intended to use through fastened metal roofing. My design goals are one and only one roof line.

In General questions | Asked By Shane Fairman | Nov 30 12
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