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1 Answer

Gaps Suggestions for Cedar Rainscreen Application

Our house is in the PNW and we will be siding it with 2 layers of 30 min felt and 1X4 cedar horizontally connected to vertical 1X1 ripped Trex Decking furring strips. We are adding fiberglass screening to the top and bottom.

Because of the wasp and other creatures and their desire to inhabit warm dark spaces, we were wondering if anyone had a good rule of thumb for gaps between the boards.

Our plan is for a 1/8th inch gap. Should we simply cover the entire surface behind the boards and atop the battens in the screen material, or will that have its own problems?

In Green building techniques | Asked By Buzz Remde | Sep 28 13
2 Answers

Will we need a sealed combustion boiler with bathroom fan ventilation?

We are building a "fairly tight" house in Central NH. It will be 2x4 construction with BIBs insulation and 2 " of polyiso foam on the exterior. We were planning on using a natural draft propane boiler for our heat, but we are now wondering if the negative pressure will cause problems. We were not planning on installing an HRV, but using bathroom fans on timers for ventilation. We are doing all the designing and general contracting for the house ourselves, and my husband is a plumber, so he will be doing the heating system (forced hot water).

In Mechanicals | Asked By Kim Krotz | Sep 28 13
1 Answer

Preferred subfloor material and adhesive for minimum off-gassing?

Does some subfloor and adhesive rate better than others for minimum off-gassing? Regular OSB is the least expensive, but are some brands better than others? and the same with subfloor adhesive; is there a healthier brand for indoor air quality or is it all about the same?

In General questions | Asked By Eric Mikkelsen | Sep 28 13
2 Answers

Slab on grade polyethylene placed below or above foam board insulation

Is there any issue placing the plastic sheeting under the foam board insulation to protect it from punctures caused by rebar placement and tears during the pour?

In General questions | Asked By bob holodinsky | Sep 28 13
6 Answers

To vault or not to vault the great room?

My husband and I are getting ready to have our retirement house built in northwestern Virginia (zone 4A). We're going for a "Pretty Good House" in terms of insulation, windows, etc... It seems that most floor plans with a master bedroom on the main level have a "great room" (approx 18x20) with a 2-story vaulted ceiling. Guest rooms are upstairs, which is perfect for us. We can orient the exterior wall of the great room to face south for passive solar gain in the winter.

In Energy efficiency and durability | Asked By Cindy Steinkamp | Sep 21 13
2 Answers

What is the best approach to insulating an unvented cathedral ceiling?

This project consist of a small ceiling area equating to roughly 80 sf. There is no form of venting currently as it was a 3 season sun roof converted from a back porch so perhaps it wasn't intended to be used as room full time. I'm in the process of changing that though, insulating what I can of the room with studs exposed. Through my journey reading over the various methods on insulating cathedral ceilings, spray foam seems the be the weapon of choice to attack an unvented ceiling space and this would be an option for me if it was affordable ($700+).

In Green building techniques | Asked By charles biek | Sep 26 13
1 Answer

What economical material to use to stop possible moisture wicking?


I am replacing bottom plates of interior walls that rest on a cement floor.

I would like to stop any possible wicking of moisture from the concrete floor to the 2x4 bottom plate.
I am considering stapling 30 min tar paper to the bottom of the 2x4 plate and then foam sill gasket material over the tar paper.
Don't know if this is a good idea or not. Is it possible to get a reaction between the tar paper and the foam sill gasket.
Don't know if foam sill gasket wicks moisture or not.

In General questions | Asked By Bill Will | Sep 27 13
6 Answers

Window flashing: no nail fin, 2" foam, rainscreen, siding

I am working on some details for a project and want to bounce a question off people here.
Wall structure is 2x6 frame, 1/2" sheathing, 2" foam (2 layers 1"), 3/4" strapping, siding.
Most details and all I have done place the nail fin on the outside of the foam with the strapping over the nailing fin. However for this project the Inline windows do not have a nail fin and we do not want to go with the expensive brick mould to add them.

In General questions | Asked By Jesse Lizer | Aug 7 12
3 Answers

Do mini-split systems qualify as a heating system for home loans?

I recently heard that mini-splits will not qualify as a heating system for Home loans because they can not provide full heating in the coldest New England temperatures. Is this true?

In Mechanicals | Asked By Ed Whitaker | Sep 25 13
7 Answers

Who makes a decent fiberglass entry door?

I've been looking at Therma Tru, Pella, and Jeld Wen. Ideally, I'd like an Energy Star door that seals well and offers decent quality. The contemporary style of our home means the door will be mostly glass, so that part is as important as the frame.

Thanks in advance for your suggestions.

In Green products and materials | Asked By Steven Knapp | Aug 25 13
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