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8 Answers

Are ductless minisplits a viable solution for a 200-year-old timber frame retrofit?

Project type: full house renovation; currently down to the stud.
House type: 200 year old timber frame style farmhouse
Location: Milton, NY, USA

We're in the midst of a full-house renovation of a building that sat vacant for 20 years. We replaced the roof and applied closed-cell spray foam in the attic and gable wall extensions. The intention is to closed-cell insulate the remained of the building envelop upon completion of MEPs.

Asked By User-6952768 | Feb 13 18
4 Answers

Questions regarding insulating a 1912 double-wythe brick building

We have a 1912 brick schoolhouse that we are renovating in Michigan. We just demoed the entire floor system including joists and main beam due to extreme powder post beetle and moisture damage.

Asked By 5grams | Feb 15 18
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).

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.

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.

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:

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.

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.

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.

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


Asked By Norman Bunn | Feb 14 18
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