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68 Answers

Why haven't steel-framed homes become more popular?

I am in the planning phase of building a home in the NJ-NY area, Climate zone 5. As I investigate my options; SIPS, double wall stick 2x4 wood, 2x6 wood, ICFs, CMU, Larsen trusses, etc.. and the myriad of permutations to insulate each one (spray foam, cellulose, hybrid batt & flash, exterior rigid foam/iso panels, etc....) I came across STEEL. My goal is as high R-value as I can get within reason $$, with hope of upwards of R-30 final values. That said, I need some objective input.

In Green building techniques | Asked By Sal Lombardo | Dec 27 12
9 Answers

Insulation options?

Zone 3 remodel (gutted)

Please help decide how to finish off the insulation on the inside.

from the outside
zip r6 sheathing
1" xps
block wall

essentially r11 on the outside of the block.

I have started to put 1" xps on the interior of the block wall and 1" furring strips... I am realizing that this is taking up 2" of space... and I have the ability instead (and probably a lot easier) to just frame a 2x4 wall on the inside instead.

I am spray foaming the roof deck with 8" of open cell.

In General questions | Asked By Dean Sandbo | Jun 22 16
2 Answers

Crawl space drainage

The best I can tell there is a spring (seep) under my house.

This is not an uncommon is our area. Most everybody has a spring or seep in their yard or around the foundation or both.

In General questions | Asked By Eric Dolly | Jun 23 16
3 Answers

How to calculate soil heating storage capacity?

I need to know how much heat in BTU can I store in a specific volume of a soil. I am using the underground soil of greenhouse as thermal mass storage. Right now I just know the volumetric heat capacity. But I want actual number of BTUs that I can store inside the soil. Do I need to measure the temperature variation through out the soil and then calculate the heat storage capacity?

In Green building techniques | Asked By Siddharth Patil | Jun 23 16
5 Answers

Insulate on top of rigid foam?

We insulated the concrete walls of our basement with 2" rigid foam XPS insulation. We taped and caulked seams. Our insulation contractor says it meets code as is (R-10) and we studded it out and plan to drywall it. Some of the space is finished but most of it isn't. One wall is partially exposed to air on the exterior. Should we add in some mineral wool or dense packed cellulose between the studs? We have mainly dense pack netted cellulose and mineral wool throughout the rest of the home. Thank you!

In Green building techniques | Asked By Kara English | Jun 22 16
11 Answers

Sizing a whole-house fan for a larger house?

Hi All,

Considering a whole house fan for our soon-to-be-built "Pretty Good House" in Central KY, zone 4A.

The house is on the larger size, and the calculations for the type of WHF I need are off the charts in terms of what is available in the marketplace (I assume), what I have attic venting for, etc.

So, keeping in mind that the fans in the marketplace are about, say, one third or one half the size it needs to be sized correctly, is there still a benefit to including one in our build?

In General questions | Asked By Clay Whitenack | Jun 21 16
3 Answers

Notched I-joist fix

We had a plumber notch our new home's engineered i-joist when installing a tub drain. We were furious but that is besides the point at this time. We are attempting to get it repaired.

Per the building inspector's recommendations, we contacted the joist company. They suggested cutting a 13" section of the damaged part of the joist and heading it off with smaller i-joist sections attached perpendicularly onto the two adjacent i-joists.

In Building Code Questions | Asked By Kara English | Jun 22 16
11 Answers

Poly and Canadian building codes

This comes up quite frequently and I thought it might be useful to lay out what is actually required by the code. My description relies on the BC Building Code, but I am fairly confident it applies to all provinces that have based their codes on the NBC.

The code requires all building assemblies to include an air barrier and a vapour barrier.

The air barrier can consist of a variety of sheet or panels materials. It can be located anywhere in the assembly. That is the inner, intermediate or outside surfaces of the assembly (

In Building Code Questions | Asked By Malcolm Taylor | Apr 4 16
2 Answers

Vapor barrier yes/no?

I am looking to insulate a new, unvented,sealed, cathedral ceiling assembly on 2 x 10 joists. I plan on shooting 3 inches of closed cell urethane foam (r18 to r20 value) directly under the plywood or aspenite roof deck, after which, I will fill the balance of the rafters with 6 inches of Roxul batt (r22 value). I will also apply ice and water shield atop the plywood roof deck, then strap it, then lay down my metal roofing. My question is, do I need to apply or should I need to apply, a vapor barrier underneath the batt before installing my ceiling gypse?

In General questions | Asked By Jean Blain | Jun 22 16
2 Answers

I am building an extension to our existing home and am preparing to insulate the roof

I am building an extension to our existing home and am preparing to insulate the roof which is a low-slope (2:12) cathedral ceiling. I am building the roof using 2 x10 rafters. The roof assembly will be completely sealed.

Many Thanks,
Jean Blain
Gatineau Quebec

In General questions | Asked By Jean Blain | Jun 22 16
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