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6 Answers

Air seal complex joint

I have a polyiso/wood and polyiso/polyiso joint that I want to air seal. So far I have been using spray foam to accomplish the task. Even with the low expanding, "flexible" window type foam, I'm not very impressed with the integrity of the seal. The foam tears somewhat easily and seems to separate with even modest amounts of force against sealed pieces. I know this problem has been covered extensively. Tapes and gaskets seem like they might be tough to use on this 3D joint complex joint. Caulking seems like it may be more robust but difficult because the gap isn't uniform.

In Green building techniques | Asked By Brian C | Dec 24 14
6 Answers

Closed-cell spray foam on roof deck... shingle underlayment choice?

Good day,

I'm planning on doing spray foam insulation on the underside of my roof deck.

I'm about to start shingling next week, and was planning on using synthetic roof paper instead of tar paper.

Then I read an article saying that on unvented roof assemblies (what this will be), most synthetic roof underlayments should NOT be used.

I did some digging, and the product I had planned to use called "Rhinoroof" has a perm rating of 0.5, aka it would create a vapor sandwich between my shingles and under deck roof insulation.


In General questions | Asked By Mark Helmrich | Dec 19 14
7 Answers

Sprayfoam house and real stone cladding. Wall sheathing?

Good day,

This is my first post, but I want to comment how much I've enjoyed reading topics on this q&a forum.

My question is regarding a new house I'm building. Zone 8 climate (cold!) similar to Alaska, 2x6 framing 16" OC walls, 1/2" OSB sheathing, no basement. Right now I'm just finishing up framing.

I've been dead set on using closed cell spray foam all around...on the interior wall cavity at 3" thick, 4" on the roof deck and 1.5" on the floor.

In General questions | Asked By Mark Helmrich | Dec 15 14
87 Answers

Modern (hydronic) heating and what all should start to know as of 2014

I stumbled upon this site to do with researching an update to a (hydronic) heating system I installed two decades ago.

So much has changed mainly the best change is the access we all have now to information.

This is the best read I have had off the internet to do with modern current (hydronic) heating.

Dana, besides your wealth of help here, this pictorial is great for the visual types like me.


In Mechanicals | Asked By aj builder, Upstate NY Zone 6a | Dec 4 14
3 Answers

Roof and ceiling design advice wanted for steel building

Hello, I have been reading a lot of posts here on roofing and insulation but could still use some advice on my project, any advice or suggestions would be greatly appreciated. I am building a steel building in Hawaii climate zone 1, 3500Sq'. Building shape either 60x60 or 30x125 with a 12 to 14' eave height. This is a live work / garage building for a small farm. The building will have a lot of awning windows up high on the walls. I would like some insulation to block the suns heat and to reduce the sound of rainfall.

In Energy efficiency and durability | Asked By Stan jones | Dec 23 14
5 Answers

Basement insulation

We just bought our first home. The basement is mostly finished, except for a side room that contains the furnace, washer, and dryer, and some storage space. We'd like to finish that room and put a small office at the end.

In General questions | Asked By Cory Kaufman-Schofield | Dec 22 14
4 Answers

Basement slab retrofit questions

I have an older home built in the 1950’s. I’ve insulated the basement walls with rigid foam and a stud wall with batts. This has made the basement more comfortable, but I still have a lot of moisture in the air based on the dehumidifier that I run frequently. I’m fairly certain that the existing slab must be un-insulated and is missing any poly or other moisture barrier under it.

In Green building techniques | Asked By Mark Fredericks | Oct 27 14
3 Answers


Why can't we click on a name and be able to send email ?

I am ajbuilderny and it is a gmailaccount.

In General questions | Asked By aj builder, Upstate NY Zone 6a | Dec 22 14
7 Answers

What to do about the existing housing stock?

Many of the articles and the focus here concern new construction, but this is an aging country with a mostly sufficient existing housing stock that dwarfs the new construction market by orders of magnitude. And these houses have the kinds of problems that make informed builders like you guys cringe.

In General questions | Asked By Nathaniel G | Dec 22 14
8 Answers

How to handle SE/SW orientation? And any experiences with Richlin windows?

I'm planning a not-quite almost-passive retrofit to a 1,400 sq. ft. 1-1/2 story Cape Cod in Minneapolis (shooting for R-40 walls & R-50-80 roof). I'm looking for a US window manufacturer who can come close to European quality without the high cost, lead time and shipping impact. Oh yeah, and the windows must be standard crank-out casement as I have no interest in tilt / turn (I've used them plenty in Europe).

In PassivHaus | Asked By Ryan Griffin | Sep 29 14
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