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9 Answers

"Crinkled housewrap" or tar paper under exterior foam?

In the "Mind the Gap" article at http://www.buildingscience.com/documents/insights/bsi-038-mind-the-gap-eh -- If I understand correctly, when covering a plywood or OSB sheathed wall with foam, Lstiburek recommends a "crinkled housewrap" between the foam and the sheathing for diffusion redistribution. Would tar paper/building felt work in this situation?


In Energy efficiency and durability | Asked By Trying to Learn | Nov 4 10
0 Answers

Green homes on wheels

Hans please tell us more about your green home on wheels!

In General questions | Asked By Michael Chandler | Nov 6 10
2 Answers

Compact space heating equipment

In the (hopefully) near future I will be jacking up my 800SF bungalow to gain some extra square footage for 2 bedrooms, a small bathroom, and a rec room. I was working on the floor plan last night, and currently I am heating with and oil fired furnace (forced hot air), in the plan I am quickly realizing that I really do not have a whole lot of room for a bulky furnace, nor do I want to sacrifice headroom for ducting. My thought was to convert to a gas fired boiler and put baseboards or rads in the upper floor, and radiant slab in the basement.

In Mechanicals | Asked By Mark Pennell | Nov 5 10
4 Answers

Installing an HRV retrofit

We have a 26 year-old home, that according to an energy audit, is too tight. It is a split level with the basement finished. We were told that we would need to install an HRV. However, we live in North Pole, Alaska and our heating system is a baseboard boiler system, hence, no ductwork. We get plenty of condensation on our windows in the winter (almost a foot last year), mold in the bathrooms (bath fans are old and not moving enough air), and our oven vent just recirculates the air, doesn't acutally move it outside.

In Energy efficiency and durability | Asked By sara mattox | Nov 5 10
55 Answers

Rigid exterior insulation with vertical siding

I am looking for the most cost-effective and energy-efficient way of installing exterior rigid insulation where vertical siding will be installed. I want to minimize thermal bridging of the wood stud framing. I have explored blocking, stripping, extra layer or OSB or plywood sheathing. Nothing is looking quite right yet. Any ideas?

In Green building techniques | Asked By Claire Remsberg | Oct 28 09
4 Answers

Wall Assembly

I am building a house using advanced framing techniques. Right now the wall assembly is gypsum, dense packed cellulose, bldg paper, 1" EPS, and stucco. The problem is, my husband hates stucco and wants siding. However, my architect is telling me there is no way to attach the siding and/or window trim. My assumption is a layer of OSB will compromise my energy efficiency. We live in Sacamento (mild climate). Any suggestions? Thanks.

In Green building techniques | Asked By Laura Sainz | Nov 5 10
14 Answers

Cool Roofs?

I am in the process of selecting the new roof for my house. I was going to choose one of the roofs that are rated by the coolroofs.org. It states cool roofs has the following benefits:

Energy savings and global warming mitigation
Reduction in urban heat island effect and smog
Improved occupant comfort
Comply with codes and green building programs

In Energy efficiency and durability | Asked By Amy Builder | Nov 2 10
3 Answers

XPS or EPS Foam on the outside of SIP

We are considering adding a layer of either XPS or EPS foam on the outside of a SIP panel house. This allows us to break the thermal bridges resulted from the wood around windows and the corners where SIPs join. Also it adds a little more R-value to our structure.

The question is about the vapor layer. One of the potential wall assembly from inside to outside is Gypsum, SIP, XPS, Furring, then cement siding. The thought is to use the XPS as insulation as well as a vapor barrier.

Another possible assembly is Gypsum, SIP, EPS, House wrap, furring, then cement siding.

In PassivHaus | Asked By Roger Lin | Nov 3 10
2 Answers

Cathedral Ceiling Insulation

In the April/May 2010 issue of Fine Homebuilding there was an article on Thermal Bridging by Martin Holladay. Included was a roof detail for limiting thermal bridging through cathedral ceiling rafters which applies to a remodeling project I am doing to my residence.Please provide information on the fasteners and procedures used to fasten the polyiso and then the furring strips to the ceiling rafters.

Thank you.

Fred Nazare

In Energy efficiency and durability | Asked By Fred Nazare | Nov 4 10
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