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8 Answers

Hi, I'm performing an energy retrofit

Hi, I'm performing an energy retrofit. My house has tiny roof overhangs and will have none after external wall insulation is applied. An unvented attic with internal spray foam and/or external rigid insulation is too expensive. I've found a product called....

My house is in Detroit (zone 5a).

In Green building techniques | Asked By Thrifttrust | Nov 2 17
45 Answers

Region 5 below grade basement insulation techniques with intention to finish

I've probably read most or all of the articles on the subject 5-6 times over, but am still left with many questions as the advice can quickly change as the circumstances do, and it's difficult to keep track of all these factors.

My goal is to finish my below grade basement in 18301 Region 5. Cape cod style home built in 1968. 954 sq ft basement.

In General questions | Asked By Ryan O'Rourke | Nov 19 17
9 Answers

I am looking at building a slab-on-grade house

I am looking at building a slab-on-grade house. I am also trying to avoid having any ductwork (or other utilities) in my attic. Where is the best place to route ductwork, plumbing, electrical, and sewer if I am slab on grade?

I wish to avoid a basement or crawlspace and their associated challenges. I also want to have the ceiling free of penetrations and no ductwork in the attic. Is it OK to run plumbing/sewer/electrical conduit under a foundation slab? I already know I want to avoid running ductwork under the slab, so I'm considering a ducted minisplit with minimal ductwork.

In Green building techniques | Asked By JB487 | Feb 15 18
2 Answers

Damp proofing for deck pilasters

I have 9 20"x20"x96" concrete pilasters on footings to be used as supports for my deck and the columns supporting the roof over that deck. Some of these are almost entirely below grade while others are primarily above grade. Do these pilasters need any sort of damp proofing to prevent freeze/thaw spalling? This is a new-build that will have appropriate drainage in Denver, CO in sandy/clay soil.

My opposing thoughts on this subject are:

In Energy efficiency and durability | Asked By Tony Arcuri | Feb 15 18
3 Answers

How to deal with metal roof condensation?


I have a detached 20' x 23' two storey garage, 100 yrs old, with an open room on the upper floor. The metal roof has a fairly serious condensation problem in late winter/Spring.

I'm in Climate Zone 6 - Montreal, Canada.

The current roof is an exposed-fastener steel corrugated gable. Around 2:12 - 3:12. The metal is screwed directly to purlins, on top of rafters, with no sheathing or underlayment. The attic floor is sloped old wooden boards covered in tar paper (I believe this was the original built-up flat roof). The additional gable structure was built on top of it.

In General questions | Asked By Leo Singer | Feb 15 18
10 Answers

Rigid insulation beneath floor on shed


First time posting and would like to thank you in advance for at least taking the time to read this.

I am building an insulated shed/writing studio for my wife. Looking to make it 12'x8' and was thinking of building it on concrete blocks with 2"x6" studs for the bottom frame. On top of that I was planning on 2" rigid insulation followed by plywood then flooring. Will I be able to put the sill plate on top of this and drill through to the 2"x6"'s? I haven't worked with rigid in this context before.

Putting it on blocks seems the best option in case we wish to move it later.

In Green building techniques | Asked By Allan Manley | Jun 22 17
2 Answers

Brick weep retrofit

Quick intro, I'm an architectural & hvac designer for a engineering firm in Ontario. Before that I worked for a carpenter with a knack for great details and learning from mistakes for all my early years. I'm re-insulating an existing 1970's home in Stirling Ontario. See the attached photo for a wall section. I've run into an issue. There are no existing weep holes and from exterior examination, it would appear there is no flashing. I cannot confirm the existence of a drainage space either.

In Energy efficiency and durability | Asked By Yupster | Feb 15 18
3 Answers

Attic access door recommendation

In my new build i want access to the attic space via a kneewall. What options are there that will provide a good seal and r-value?


Mixed Humid


In Energy efficiency and durability | Asked By Norman Bunn | Feb 14 18
4 Answers

Water-resistant insulation

We are rebuilding many small buildings (Not Houses) that were flood damaged by Hurricane Irma and have a small probability of flooding again. They are 2"x4" framed walls, sheathed with 1/2" plywood, covered with #15 building paper or house wrap and sided with vinyl or cement board. Remediation work included removing all wet drywall and fiberglass insulation, cleaning and disinfecting the wall cavity, and drying the framing lumber and sheathing to a moisture content of 8% or less.

In Energy efficiency and durability | Asked By Anthony Swoope | Feb 14 18
4 Answers

LSL Framing

I'm planning on building a small cabin with some laminated strand lumber (LSL) framing. I'll be doing 24 inch on center, so I'm going with LSLs for some additional strength. Straighter walls and easier installation are added benefits too. LSL lumber is very expensive, so I'd like to just use them for the studs and then use standard dimensional lumber for top and bottom plates. I'm trying to find a cost effective way to incorporate some of the benefits of LSLs. I'm thinking that warping is less of a concern for the top and bottom plates.

Is there any concerns with this approach?

In Building Code Questions | Asked By Rodrob15 | Feb 14 18
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