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0 Answers

Looking for local GBA contractor in Chicago IL

Hello, I am looking for someone in the Chicago IL area to help guide me in building an underground roof. Do you have a list of contractors that are Green Builders in the IL area? Thank you!

In GBA Pro help | Asked By bawhitn | Oct 19 17
2 Answers

Recognizing unsafe vermiculite removal

We have lived in our 1960s built home for about 5 years, and are trying to make some improvements. A low ceiling needed to be opened, maybe add some skylights, as well as redoing electrical work in the ceiling.

In Energy efficiency and durability | Asked By iinva | Oct 19 17
3 Answers

Low-ceilinged small bathroom in Zone 4, built in 1930: How to insulate?

The home has a metal roof with good dow corning underlayment. It is sloped and is a low ceiling at outside wall. I wanted to use Closed cell spray to Insulate . I have been closing up all soffit vents. I have to gable vents on house. My concern is having roof deck rot. Should i leave a 1/2 inch gap and vent to attic ? The area is a wrap around porch connected too main house that has been closed in over the years. The ceiling joists rest on top plate of main house.

In Energy efficiency and durability | Asked By Greenconfusion | Oct 18 17
3 Answers

Plywood sheathing over rigid foam

THIS IS LONG BUT PLEASE BEAR WITH ME. Any advice on this project would be greatly appreciated! My home is located in the 6A zone. To start I purchased a home 3 years ago and decided I wanted to replace the windows and doors. The house was built in 1978. Upon further inspection of the home (which my home buyer inspector did not catch) I discovered that my house does not have any wood sheathing. It was built with 1in blue tounge and groove styrofoam board and had aluminum siding attached to it nailed to the wall studs. The rigid foam was never taped at the joints either.

In Plans Review | Asked By Rg14 | Oct 18 17
7 Answers

Heat loss, can lights in cathedral ceiling

The information about replacing or retrofitting can lights with LED fixtures has been really helpful. However, I have a cathedral ceiling with what I think are standard can lights, with a diameter of 7.5" within the can, and about 9.5 " total diameter including trim--the ceilings are about 18' high so I am having a difficult time getting to one to carefully measure.

I cannot find anywhere residential can light LED retrofits for this size. I've looked at what Cree offers, as well as Home Depot and Lowes, and they all max out at 6".

In Energy efficiency and durability | Asked By JWBDSR | Oct 17 17
0 Answers

Multiple condensers vs multiple heads

A quick search found little info , I am curious on the virtues for multi head ductless vs multiple stand alone mini splits. How much of a penalty would be paid for electric usage? I see more wiring , having a breaker and disconnect for each, however the upside that if one went down you would have backup. Obviously you would need to do this in a situation where you had heads on different ends of a larger home. My other thought is you could mix and match units.

In Energy efficiency and durability | Asked By scott mangold | Oct 19 17
2 Answers

Insulating a beehive for winter

Bees seem to need our help more and more these days. They do not hibernate, but cluster together to create warmth, and subsequently create moisture by breathing. That can turn deadly unless there is a little ventilation. Therefore, there are openings top and bottom for ventilation and for bee flights on nice days. Traditional hive wraps are black roofing felt (tarpaper), or a black plastic covered fiberglass blanket "wrap," or my current 1" silver foil-faced rigid foam. I like the idea of 2" foam (strapped like a box around the hive) but wonder what will happen in the elements.

In Energy efficiency and durability | Asked By Brownew | Oct 16 17
19 Answers

Are my minisplits modulating or short cycling?

Hello- first of all this site has been an incredible resource. I did most of my own research in adding 4 mini splits to my 1940's home. It was primarily for AC and heat for the shoulder seasons as we really enjoy our 1 pipe steam heat (although older boiler). I went with 2x Fujitsu (not XLTH) condensers with 2 heads each. A 12k per floor (open kitchen area, top of stairs, attic playroom), and 7k in the master.

Home has been retrofitted with new windows, open cell in the rafters, blown-in in the walls, etc...so definitely on the tighter side for it's age.

In Mechanicals | Asked By Kjmass1 | Oct 4 17
6 Answers

Vapor barrier needed if interior walls are horse-hair plaster?

I plan to put new, pre-stained cedar shingles on the exterior of my 1920s bungalow this spring. This is the only side of the house that hasn't been renovated. Earlier renovations to other parts of the house revealed tar paper under the shingles, so I assume we'll find the same thing under these shingles. The interior wall is horsehair plaster and there is no insulation (this is the only exterior-facing wall in the house that still has horse-hair plaster). I've read some confusing posts about Tyvek/Typar and moisture barriers. Do they create moisture problems with horsehair plaster?

In Energy efficiency and durability | Asked By bonbar15 | Oct 16 17
8 Answers

Summer cabin retrofit

We bought a 70's tongue and groove cathedral roofed cabin in Meyers Ca. I think the winter is a region 5. The current shingles are unfortunately in too good a shape to tear off but ultimately i will put 6" of cc foam and a cold raised seam roof with some sort of screen to prevent spark entry. I have spent the last 60 days of spare time addressing the down slope water issues by installing a french drain and water proofing the foundation and removing the mostly fallen fiberglass from under the 4' centered beam crawl space.

In Energy efficiency and durability | Asked By Mike Wanless | Oct 16 17
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