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13 Answers

1. Window square footage? 2. "Effective R-value"?

Hello, and a big thank you to all the experienced voices out there who contribute to this blog. We are trying to design a 1700sqft timberframe (slab on grade zone 6A southern Maine). We are looking at windows and after reading this blog for weeks there doesn't seem to be real consensus on how much window area to put on a south wall. I agree that envelope design may have won out over passive gain, but I also agree with some writers that a sunny room just feels better, and it is hard to quantify that. Is there a general ballpark to shoot for?

In Energy efficiency and durability | Asked By Robert Young | May 8 16
6 Answers

Mini split head - mounting location considerations

I'm interested in feedback on what must be a common dilemma with mini splits - where to place the indoor head unit when the best location for aesthetics, function, proximity to the outdoor condenser unit, and gravity condensate draining are often in conflict with each other.

I'm most interested in opinions about how much weight to put on a location that will not require a condensate pump - what are the issues there - but decided to open up the question further as these various considerations are probably a source of struggle to many people.

In Mechanicals | Asked By david jensen | May 11 16
6 Answers

Exterior foundation foam

Hi All,
My original crawl space insulation plan called me for me insulating the interior of the foundation. Well it turns out after reroutingng the downspouts and correcting grade issues I still had water problems. So I dug an exploratory hole and discovered the foundation has no water proofing on it. So since I have to dig the entire foundation out any way to water proof it I might as well install the insulation on the exterior.

In Green building techniques | Asked By Chris King | May 9 16
8 Answers

Minisplits and moisture removal effectiveness

Considering that the better variable refrigerant flow mini split heat pumps, sized properly, are designed to operate largely without cycling off, it would seem that they would offer superior latent load performance (moisture removal) over the typical cycling split system. Is that true in the real world? I'm specifically interested in performance in high humidity environments like here in central Florida.


In Mechanicals | Asked By David Jensen | May 8 16
8 Answers

Another basement finishing question

I recently purchased a home and would like to turn the area into a family room with a wet bar with porcelain tile floors. I am having trouble figuring out what the best way to do this.

Facts about basement area:
- Frame house with brick veneer built in 2006
- Climate Zone 4
- Utilized previously as storage / laundry room
- Semi finished
- 800 sq ft & 9 ft height
- 66% below grade
- Cheap carpet over the concrete slab as flooring
- Drywall seems to be directly affixed to the concrete (see attached picture)

In General questions | Asked By James Wong | May 7 16
6 Answers

Peel & stick membrane on top of ICF exterior walls?

I am building a house with ICF walls....the lower level (3 walls in-ground) we are planning to finish using wire lathe & stucco on the exposed portion and the 1st Flr Level (all above grade) we are planning on installing 3/4" vertical lathe and horizontal Hardiplank.

The question is should I install a peel & stick membrane on top of the EPS foam as a WRB or is the EPS foam sufficient for this purpose? If the peel & stick is recommended, can you recommend a particular make(s) to use? Thanks!

In Energy efficiency and durability | Asked By Jonathan Scholl | May 9 16
15 Answers

Using far infrared heating for in-floor heating of a house

I came across a product....Geo Dream carbon film .....at the GreenBuild 2015 Conference in Washington DC and I am interested in anyone's comments about its use and performance. I have spoken with the North American supplier ....located in Vancouver BC... and some of their installers and everyone speaks very highly of the product and the fact that it can be used as the sole source of heating for the home. We are building an ICF home in Climate Zone 5 and are quite interested in using the product.


Comments welcome! Thanks.

In Mechanicals | Asked By Jonathan Scholl | May 9 16
4 Answers

Serious problem with anti-siphon valves

We have anti-siphon valves on our exterior spigots, as code requires. I understand why these are necessary and that they are important. But they spray water out all over the house siding every time the water pressure changes i.e., if the washing machine is running or someone inside uses a faucet. We are beginning to have problems at the area of the house that is constantly wet. I'm seeing carpenter ants now. Isn't there some better way to prevent siphoning from the garden hose without this issue of water spraying out all over the house siding continually?

In General questions | Asked By L H | May 7 16
2 Answers

Do basement stairs have to be enclosed?

Hi all,

Just checking code. I will have a basement, and at the top of the basement stairs I will have a door. Does the staircase down to the basement have to be enclosed, and a door at the bottom of the stairs?

If it matters, I will have engineered I-beam floor joists between the basement and 1st floor, which I understand have a little bit different fire code requirements?

In Building Code Questions | Asked By Clay Whitenack | May 9 16
7 Answers

Roof structure, insulation and lighting

I am planning a new home in northern Idaho climate zone 6 and have some questions regarding the roofing structure/insulation and lighting within this system. this will be a mostly cathedral ceiling with a flat part across the middle in which I intend to put the lighting and ceiling fans. The thought is to keep these items out of the insulated roof. It will be a non vented roof. I have attached two drawings to help illustrate my thoughts. I would like to build the roof as follows from top to bottom:
1. Dutch Seam metal roofing
2. 2x4 furring strips

In Energy efficiency and durability | Asked By Kyle Rice | Apr 28 16
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