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10 Answers

Reading about rainscreen siding systems it seems that the recommended gaps are typically 1/2" to 3/4" between the housewrap and and the back of the siding. Is there any reason why one couldn't do a very large gap using thicker furring material? Maybe around 3" or 4" between the siding and the sheathing for architectural reasons on a remodel? Would there be problems with having that large of a gap?

In Green building techniques | Asked By Kevin Hardy | Jul 26 14
6 Answers

Hi All,

We are using Foamglas for insulating under our slab as well as the slab edges (monolithic slab on grade). It is a requirement to leave a 2" gap above the Foamglas on the slab edges for termite inspections. Are there any options to satisfy this requirement, but not have the thermal gap? Perhaps industrial strength velcro or something :) ?

Thank you,
Stacey Owens

In Green building techniques | Asked By Stacey Owens | Jul 18 14
8 Answers

(Examples of what I am referring to can be seen at: http://vastern.co.uk/wp-content/uploads/2013/03/Splayed-cladding-detail.jpg AND http://www.bartonqualitytimber.co.uk/images/categories/chestnut%20claddi... )

I am not terribly conceded about the cedar: if it is stained all 6 sides with two coats and placed on black painted strapping, then it should handle the elements reasonably well. My main concern is what the substrate behind it should be.

In General questions | Asked By Burke Stoller | Jul 18 14
24 Answers

I had R60 blown into my 1000sqft attic where there was previously only about R11. Baffles were installed in almost every roof rafter. Air sealing of attic floor was performed. This is a low pitch asphalt shingled hip roof over the whole house.

In General questions | Asked By Jeff Watson | Jul 12 14
2 Answers

This question might have an obvious answer, but I haven't been able to dig up anything on google. If I were to purchase a tear-down property that had an existing uninsulated, fieldstone basement, what would be the best course of action to build a high performance house? Fill it in with dirt then to then create a slab on grade? Tear out the fieldstone and use the existing cavity to create an insulated basement (while also hopefully re-using the fieldstone on site for something useful like a wall)?

In Green building techniques | Asked By Ethan Fahy | Jul 21 14
3 Answers

We had our basement encapsulated in the fall last year and made it through winter no issues. They used a thick mil high quality (apparently) vapor barrier and then sprayed /fogged with mold preventative. I don't think there is any more mold - smell is not musty really and I don't get a mold allergy reaction.

In General questions | Asked By jeff weikert | Jul 22 14
19 Answers

I am not in construction or an architect, just someone who would like to live in/build a small, comfortable, energy efficient home. I don’t need and could never afford a Passive House. Don’t even know if one would work where I live. I live in the low desert southwest near Phoenix. Living is very different here than in cold weather areas. And very different than Florida or humid areas of Texas. Outside temps over 100F in shade 5-6 months; highs 115F; nighttime lows 95F for at least 2-3 months. Low humidity 10 months. Little or no drought resistant shade trees.

In Green building techniques | Asked By Anneal G | Jun 27 14
4 Answers

This is probably only a hypothetical question as I doubt I could talk my wife into a composting toilet but…If we have a tight home with balanced ventilation, and if we had a composting toilet that has a small 5W fan continuously exhausting air - how would we provide make-up air?

In PassivHaus | Asked By Scott Tenney | Jul 24 14
3 Answers

Investigation revealed 3 problems: 1) no soffit vent; 2) insulation extending beyond the end of plastic rafter vents closing off the air channel up to the ridge vent; 3) no blocking above the wall to seal up the fiberglass. I've corrected the first two and caulked the ridge on the inside, but am unable to fix the blocking. The odor persists and I fear the fiberglass is contaminated with mold that the revived air flow won't be able to dissipate. Would pulling out the fiberglass (through the soffit to avoid major deconstruction) and filling the bays with foam work?

In GBA Pro help | Asked By Michael Roland | Jul 25 14
3 Answers

As a long time visitor and few years member, I have tried to absorb the lessons, opinions, science and conjecture presented here. However, I now find myself confronted with conflicting theory regarding unvented roof profiles.

For my own project, (high altitude, dry, -10 to 90 F) I have regarded the "top" layer of sheathing in an unvented assembly to be essentially in dead space - not exchanging air or moisture - the underside in contact or glued to impermeable insulation, the top side sealed off from all contact with the locally required ice and water shield over the entire roof.

In General questions | Asked By Roger Berry | Jul 24 14
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