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2 Answers

Converting can lights

I have 8 recessed/can lights in my home. They are not ICAT rated, so there is currently no insulation around these fixtures. No air sealing, either. We're adding cellulose insulation within the next few weeks, so I'd appreciate some advice on how to deal with these dang lights.

We priced replacing with ICAT fixtures, but it's too expensive. Also considered removing them entirely, but that's even more expensive and time-consuming. We ordered some LED retrofit inserts (Cree C6), but they are too bright (625 lumens) and the depth of the light causes shadows that we dislike.

In General questions | Asked By Green Heron | Nov 22 15
4 Answers

Insulating with nailbase panels

I've been thinking about building with SIPs and am waiting for a quote from a local dealer. But, I've also had an idea about using nailbase panels that could be cheaper. What about framing with 2x4 studs and then sheathing with nailbase panels but with the foam side facing in, and the OSB side facing the outside? I could then spray foam the interior a couple inches, and be able to attach cladding directly to the OSB. Any thoughts on this? Has anyone tried this before or think it would be effective? (Building in Michigan - climate zone 5) Thanks.

In Energy efficiency and durability | Asked By Brian W | Nov 20 15
2 Answers

Using well water for air conditioning

A random thought occurred to me while I was thinking about the Chiltrix system. For air conditioning, water at about 55 degrees would be circulated through the fan coils. That is about the temperature of the water coming out of my well all year. If the system was only used for air conditioning, could the well be the source of the cold water as opposed to running a compressor? I don't see a problem with this idea, but I expect that if it was simple at least some people would be doing it. Am I missing a major flaw?

In Mechanicals | Asked By Reid Baldwin | Nov 21 15
2 Answers

What is the best way to have a 28' chimney pipe cleaned on a high efficiency wood stove?

I just wasted 48.00 and was told my high efficiency wood stove can not be cleaned from the inside up because of the smoke baffle inside of it? I didn't even know it had one. They are telling me I will have to rent a cherry picker because my roof is to high and steep to clean it from above. Plus I assume now my chimney cap is not the correct one because I found out it leaks. Not around the wall but down the pipe, I found my ash drawer full of water. Other than getting rid of my wood stove I wonder if you have any comments or suggestions?


Susan Evans

In General questions | Asked By Susan Evans | Nov 21 15
18 Answers

Specific advice on Mitsubishi mini-split system in region 5

Have had several local companies provide quotes on Mitsubishi mini split systems for my home. Have seen wildly different Manual J calculations, as well as different recommendations on equipment, some conflicting. Can give more info if requested.

In General questions | Asked By Ryan O'Rourke | Nov 18 15
13 Answers

Moisture management for tiny house subfloor?

My husband and I are just about to start building a tiny house on a trailer in Nashville, TN, and I'd like to make sure our subfloor does a good job of protecting against moisture, as well as drying out when necessary. Any advice would be greatly appreciated!

Our current setup, from bottom to top, is:

- Steel trailer frame
- Metal flashing
- 2x4 framing filled with Roxul, anchored to steel flanges on the trailer using bolts
- 3/4" Advantec with taped seams, which will connect to ZIP system sheathing as our air barrier
- Cork floating floor

In General questions | Asked By Michaela Riley | Jun 20 15
2 Answers

Foam insulating a roof that has 1x8 sheathing with large gaps between the boards?

I have a sixty year-old house, and want to spray foam in the attic, on the underside of the roof. The roof sheathing consists of 1 x 8 boards, and the spacing between the boards varies from 1/4" to 1/2". There is an ice and water shield underlayment and asphalt shingles on the roof. I have two questions: When the foam is applied will it expand through the gaps in the sheathing and cause the underlayment and shingles to lift? Do I somehow need to seal the gaps before the foam is applied? Will it make a difference if I choose to use open or closed cell foam?

In Green building techniques | Asked By Ron | Nov 18 15
6 Answers

Sealing in flame retardant foam in furniture

Hello all,

I recently learned that polyurethane foam in furniture oftentimes has flame retardants that are carcinogenic. These flame retardants escape from the furniture and become a part of the household dust which can be breathed in or swallowed. I have seen suggestions to buy new furniture that has no fire retardants or replace the flame retardant foam with non flame retardant foam. All of these options are quite expensive. Does anyone know if it is possible to encapsulate flame retardant foams so the flame retardants cannot escape into the air or at least greatly reduce the spread?

In General questions | Asked By John Doe | Nov 20 15
4 Answers

Air quality sensor / controller?

After much time spent thinking about an air exchange system retrofit for my home, I'm amazed at the installed cost, and am left questioning the necessity of it all. I reputable installer has quoted me $3,500 to $4,000 for a HRV-based air exchange system, so I'm wishing for a cheaper and/or more scientific way to determine my home's ventilation needs, other than something that just vents continuously regardless of conditions.

This article intrigued me:

In Green building techniques | Asked By Ryan Griffin | Nov 20 15
18 Answers

Do screws through exterior insulation reduce the wall R-value?

I was in a Net Zero Building class this weekend and there was mention that screws that are used to attached exterior insulation reduce the whole wall R-value by 39%.

The screws are attached from the outside thru the rainscreen, insulation, WRB, sheathing and into the framing.

This individual referred to an article from Energy Design Update (no issue was noted). I'd check but $600.00 for a subscription is too rich for my pockets.....

Any help here on the article or data at least, with other references?

In General questions | Asked By brad hardie | Mar 1 15
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