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11 Answers

Site built ventilation baffle moisture issue

I installed site built rigid foam ventilation baffles per GBA article http://www.greenbuildingadvisor.com/articles/dept/musings/site-built-ven...

In General questions | Asked By Michael Prisco | Nov 17 17
2 Answers

1-1/2" wide rigid foam strips on interior of wall studs?

I was recently speaking with a contractor who said a builder he knows of is installing 1-1/2" wide strips of rigid foam on the interior side of each wall stud to stop thermal bridging. He is doing this as a more affordable method than applying rigid foam to the exterior. He is the installing furring strips for drywall. Is anyone doing this? I am also curious how thick these strips would have to be to effectively stop thermal bridging. It seems reasonable to me but I want to make sure this approach would be beneficial.

In Energy efficiency and durability | Asked By Brian Ducharme | Nov 17 17
1 Answer

Primary Damper for Tulikivi wood stove?

Climate zone 6, Minneapolis.

I had a Tulikivi wood stove installed last week. The double wall stainless steel chimney has not been installed yet. There was no plan for a primary chimney damper. I feel the need to be able to close or reduce the draft when there isn’t a fire going. It would be left completely open when we have a fire going.

In General questions | Asked By jim sweazey | Nov 17 17
9 Answers

Helping my insulation contractor make the right decisions. :)


Good insulation contractors around here are hard to find. A lot of people are doing the work without understanding many of the techniques shared on this site and others. I talked to the person I am considering for my new house and I think I could use your help in educating him a little.:)

1) Radiant barrier in attic

In Energy efficiency and durability | Asked By Norman Bunn | Nov 17 17
8 Answers

Flashing Bottom of Window flange?

I've noticed that a lot of builders will omit taping over the bottom flange of a window once it has been installed. Sides are taped/flashed and the top flanged covered by WRB flap. Yet, bottom flange is left exposed.

I presume this is to allow water to drain from the assembly. But is this really necessary- especially if weep holes are left uncovered? Will this result in air leakage at the bottom of window?

In Energy efficiency and durability | Asked By Rick Evans | Nov 16 17
4 Answers

How to insulate rim joist that doesn't breathe on the exterior side?

The home was built is 2012 we are in Zone 5b just north of Indianapolis. We are the original owners and have pics during construction phase (unfortunately they were not custom builders and would not let us help with design details. e.g. we couldn't get them to insulate exterior basement walls and below the slab with rigid foam- which is now MADDENING).We are about to finish the unfinished basement. What is the correct way to insulate a rim joist on a modern house?

In Green building techniques | Asked By user-6955054 | Nov 16 17
7 Answers

Grounding a Steel Deck Frame

I'm building a weekend cabin designed along the lines of a fire lookout tower. As I am in an wooded area with high potential for wildfires, I am trying to use materials which minimize fire risk. The building footprint is a 22' square and will be constructed using Faswall blocks covered with steel siding and a steel roof. The upper level will have a wraparound "catwalk"-style deck about 15' above ground level. The deck frame will be constructed of hollow structural steel supported by braces anchored to the building walls and the actual decking while probably be a composite decking material.

In General questions | Asked By David Williams | Nov 12 17
1 Answer

Poor Man's Thermomass

The previous conversation got off on a tangent about material costs and PWF... There was not much uptake on my "Poor Man's Thermomass" idea: http://www.greenbuildingadvisor.com/sites/default/files/poormansthermoma...

Since drawing that detail, I have thought about replacing the EPS with rockwool, and have done some research on what the backerboard could be. I understand it can't be Hardibacker or Durock. Perhaps there is another subgrade cementitous board which would be applicable?

In Green building techniques | Asked By Ethan T ; Climate Zone 5A ; ~6000HDD | Nov 15 17
19 Answers

Marine Zone 4 — Wall insulation — addition

Zone: Marine 4
Location: Seattle, WA
House Built: 1915
Square footage: 900 ft2 single story with 900 ft2 finished basement.
Wall height over basement: 12 ft
Current siding: Cedar, Paint in poor condition.
Insulation: not much, some fiberglass bat stuffed in nooks and crannies as they opened walls in the past. And dirty so there is plenty of air gaps.

GOAL: Comfort

In Plans Review | Asked By User-6933356 | Oct 11 17
2 Answers

Should I use a poly-type Membrain sheet or vapor retarder paint for ceiling?

I'm at a crossroads with how to deal with the ceiling vapor retarder in my new construction home in climate zone 5.

I'm prepping for drywall, and am wondering if I should apply Certainteed Membrain vapor barrier to the underside of the studs on the ceiling, and then just have the ceiling drywall screw attached...


Should I have the ceiling drywall glued and screwed and use vapor retarder paint instead.

I plan on blowing R60 cellulose in the attic when done, and am concerned about it's weight on the drywall.

In Green building techniques | Asked By Adam Peterson | Nov 14 17
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