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3 Answers

2-part spray foam: Store-bought kit or professional application?

New home build in CZ 6A. While discussing my cellulose insulation requirements with a local supplier, he tried to sell me on spray foam for both the rim-joist and below-slab in the basement in addition to the cellulose for my walls. I explained to him that sub-slab spray foam was likely out of our budget and that if I did spray foam in the rim joists it would only be a thin coat for air sealing purposes, and that I would probably do it myself with a store-bought 2-part foam kit.

He made some claims to back up his argument:

In Energy efficiency and durability | Asked By Lance Peters | Dec 1 17
2 Answers

PH questionnaire

I am an undergraduate student in University of Patras and I'm currently working on my thesis about a retrofit PH located in Athens. I am conducting 3 questionnaires about PH. One for the PH adviser, one for the manufacturer/engineer of the PH and finally one for the users/owners of the building. What are the most representative questions someone can ask each person of the category so as to conclude about the general function of a specific PH?
Thank you :)

In PassivHaus | Asked By danaezoupa | Dec 4 17
6 Answers

Window with stone veneer below

Siding to Stone Veneer Transition. Flashing used between two claddimgs at transition point. Windows sit right above stone veneer, and have sloped downward sills as part of the windows themselves. Stone veneer directly below. Slicker Max used rainscreen.
Would anything be required below the window, with an already sloped sill, above the stone veneer. Trying to find something similar to what am describing to upload.

In General questions | Asked By Birdie L | Dec 2 17
9 Answers

2-inch foam on the interior face of the wall: What are my electrical box options?

Due to a foundation snaffu, it looks like I will have to move my 2in. EPS foam to the inside of the wall assembly. Although that seems feasible, it will add some labour and material cost (3/4" strapping everywhere, 3/4" plywood for the kitchen/cabinet area etc.)

I was specifically looking at the extra pain involved in installing electrical boxes. It seems most of the box extension rings I could find are limited to 1.5", which is a bit shy of the 2in. I would require.

In GBA Pro help | Asked By Mai Tai | Dec 2 17
13 Answers

2nd floor is colder than the 1st floor in an ICF home

Hi All,
New home, with the 'guts' built by a (rather poor) contractor.
Walls are 6-8" foxblock ICF with energy sticks. Attic insulation is R50. So should be very tight.

Single stage gas furnace. Installed by amateurs, Builder refuses to adknowledge problem and his trades' incompetence since day 1. Not having a lot of luck bringing them back, and we are speaking through lawyers at this point...let's just say that during the walkthrough we discovered the HRV inlet/outlet lines were reversed, so little/no fresh air was being drawn into the house.

In General questions | Asked By Roberta R | Nov 29 17
2 Answers


I attended a series of exceptional lectures by the German Architect Kay Künzel a few years back associated with Passive House Hudson Valley.

He had the perfect level of German arrogance or dismissiveness that really made me wonder why the things he was discussing aren't more common in my neck of the woods.

In General questions | Asked By Ethan T ; Climate Zone 5A ; ~6000HDD | Nov 30 17
21 Answers

Sizing a ductless minisplit for heating

Hi all,

I'm going to install a ductless heat pump. I settled on LG Art Cool Premier (HYV1 or HYV2). Now I need to figure out system size, and there is too much info.

I have 550 sf addition built in late '80s, which is a split lever open space, and is VERY cold (i've attached some photos)!

It has a large french door (8x10' glass, 3 sections), 7 windows, and 5 skylights. All are double glass.

In General questions | Asked By Levab | Nov 16 17
9 Answers

Ensuring a non-load bearing wall is as such (double stud wall)

Simple framing question (I think) pertaining to double stud wall construction.
Should anything be done to ensure that the 'non-load bearing' wall is truly not bearing any load, such as making it a bit shorter than the load bearing?

The specifics are as follows: A garage with concrete stem walls and interior slab. The exterior wall is load bearing on the stem walls. The interior wall (to be built) will be resting on the slab, therefore should not be load bearing. The load is a simple trussed roof, 24' oc.

In Green building techniques | Asked By Tyler Keniston | Nov 29 17
8 Answers

Sand and filter fabric over foundation drains

We're trying to put in a foundation drain that will be trouble-free for years. Pretty much following the suggestions on this site - using rigid pipe, wrapping the filter fabric around the gravel like a burrito, etc. Now we come to the question of how to protect the filter fabric from getting clogged. We asked our builder how much it would cost to get a load of coarse sand to cover the filter fabric. He came back with a price ($500) but as I asked more questions I found out that what he's really trying to get us to use is #10 gravel. I have some concerns about that ...

In General questions | Asked By William Costello | Nov 30 17
7 Answers

Rigid foam: glue vs. fasteners

I'll be installing 2 inch Thermax to the inside of my poured concrete foundation. I don't yet own a hammer drill, but I'm looking for advise on the best way to attach this material to the wall. I've read about glue only, plastic fasteners, metal fasteners, and strapping. Which are the easiest to install and will last the life of the house?

In General questions | Asked By Andrew G | Oct 31 17
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