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33 Answers

Ductless minisplit - completed Manual J


Asked By Jeremy Archer | May 1 17
2 Answers

Stucco patching (no air gap possible)

When patching historic stucco, what's the best WRB to use?
Here I'm patching a couple hundred sf of 1938 stucco, installed with over single layer of paper (quite thin tar paper apparently, where it can be found, which is not everywhere due to termites).

Do I go with two layers of Grade D paper, and hope the outside layer wrinkles to create a bit of an air gap? I'd like to go with a drainage mat, but there's a need to match the existing wall thickness.

What's the best practice for stucco patching?

I have read:

Asked By Bryce Nesbitt | Dec 15 17
20 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
2 Answers

Is closed-cell foam risky in this assembly?

I’m building a new home on the southern border of CZ 7 in Minnesota. I have 3” of Halo Exterra EPS over Zip with 2x battens. The 2 X 6 wall will be filled with R21 fiberglass batts and no interior vapor barrier.

The floor system is 18” trusses, top chord on one end, bottom chord bearing on the other. I plan to spray foam the top chord bearing truss spaces because they have concrete on the exterior. I am considering spraying the exterior wall of the bottom chord truss space as well, but that has foam on the exterior.

Asked By Dave Ahlquist | Dec 14 17
1 Answer

Garage Wall Insulation


Asked By Mike McLaine | Dec 14 17
1 Answer

Does insulation under the flooring + a sealed floor = vapor sandwich?

I have a pier & beam house in Austin with cold floors. I'm considering insulating the underside of the flooring, by either stapling polyiso foamboard across the floor joists and then sealing the joints with tape, or else having closed-cell foam sprayed into the joist bays. If I then seal the hardwood flooring, will that create the dreaded "vapor sandwich", because I'd be locking in moisture from both sides? If so, can I proceed anyway if I run a dehumidifier in the living space and test the moisture content of the wood before sealing?

Asked By Michael Bluejay | Dec 15 17
1 Answer

Historic renovation

This might be the first of many questions I for this community. I've been lurking for awhile and heard about this site from the guys on FHB.

Asked By twoodson | Dec 15 17
12 Answers

Air sealing strategy for north Idaho ranch

I'm working with a builder who is not a "green builder". My perception is he does practice good technique in terms of installing and sealing windows and doors but has not been tasked with achieving a low air infiltration in the past.
In order to get to my goal (3.0 ACH50), I put together this strategy, see attached. My thought is to identify the actions he will execute to get to my goal.
Does this list look like it is enough? Am I missing any big bang for the buck items?

Asked By Steve Wolfe | Mar 9 17
17 Answers

Help selecting a heat pump

Hi Guys,

I'm going to be meeting with my builder this week, and he wants to show off the furnace of his choice, which is a Dettson Chinook. It's a small modulating natural gas unit, that can be paired with their Alize heat pump.

It's a pretty neat unit, designed to allow for very long cycle times, often measured in hours. The problem I have is that the heat pump portion kind of sucks in cold weather, it uses proprietary small high velocity ductwork, and a proprietary thermostat to control it all. It also has a short~ish warranty.

Asked By Stephen G | Dec 11 17
11 Answers

Workshop with dwelling above: Heating advice?


Asked By User-6964558 | Dec 12 17
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