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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?

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!

Asked By Kara English | Jun 22 16
12 Answers

Does anyone have experience with Zehnder ComfoFlex?

We are building a new house and in the final stages of design. The design includes an HRV and Zehnder ComfoTube looked great until I discovered that it is not UL listed. So, I'm curious if anyone can provide feedback on ComfoFlex. There isn't much on the intertubes...

Asked By Trevor Fontaine | Feb 9 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?

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.

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 (

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?

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

Asked By Jean Blain | Jun 22 16
5 Answers

Dimple board on a pre-cast concrete basement

I just had a pre-cast basement installed that uses 8000 psi concrete. The majority of the basement is below grade. They told me that I don't have to do any type of water proofing, but since I haven't back-filled yet, I'm going to go ahead and do it anyways for peace of mind. I like the idea of the dimple board membrane except for the fact that you have to nail it into the wall. I don't want to create holes in a wall that is solid! Any ideas if I can install the dimple board without nails?

Thanks in advance!

Asked By Andy Spears | Jun 21 16
4 Answers

How to repair the concrete sill under our front door?

We've been having some issues with water leaking into our basement under our front door. We have a metal threshold over a concrete sill, and our front porch is a concrete slab about 4'x6'. There are a number of weatherproofing issues we need to address, but the most urgent is the concrete sill under the door which has been crumbling for a while and presumably is the source of our leak. I've removed the threshold and cleared out most of the loose concrete so I could see what was underneath. Here are a few photos:


Asked By Cory Kaufman-Schofield | Jun 16 16
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