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34 Answers

The differences between mass and insulation

The "I installed more attic insulation and now my AC runs more" thread got me thinking about the mass effect a bit.

Asked By Nathaniel G | Sep 15 14
0 Answers

Where Did Vestibules Go?

With all the emphasis on energy efficient building enclosures and air sealing, what happened to the vestibule? A fair amount of thought goes into the energy penalty small leaks represent to a well sealed house, but surely opening the main entry represents a significant air change, especially if it is windy or you are talking to someone who has knocked on your door.

Asked By Malcolm Taylor | Sep 18 14
0 Answers

Air and moisture proofing.

I am going to be renovating a 1950’s house in Toronto, ON. It’s a 1 ½ storey that we are making 2 storey with adding addition on the back and attached garage. The plan for the 2nd storey is wrap the outside in Blueskin then cover in 3” Roxul Comfortboard IS, Strap and vinyl side. 3 of the 1st floor brick walls are to be left in place, which I also want to cover in 3” Roxul strap and vinyl side, but unsure what to use under it to keep the air and moisture out.

Asked By Dave B | Sep 18 14
0 Answers

Thoughts on Insulating Renovation

I ‘m trying to decide what insulation value to go with on a house we are renovating in Toronto, ON. It’s a 1 ½ storey that we are making 2 storey with adding addition on the back and attached garage. The 1st storey walls are to be left, 1950’s double brick walls no insulation. The 2nd storey I would like to go with either 2x6 with R24 Roxul or 2x8 R28 or 2x4 x2 with 3xR14=R42 and 3”Roxul Comfort board IS R12 on the outside., So I get either R36/R40/R54, but on the main floor inside I can only go 2x4 R14 or 2x6 R24 max, plus I’ve been told the brick =R4????

Asked By Dave Bentley | Sep 18 14
6 Answers

Conditioning and venting a small cellar - Western NY

Gentlement, what do you advise?

Option 1 - Supply and return of conditioned air approach: Seal the cellar and exchange conditioned air a supply and return approach using 2 or more floor vents/registers between cellar and the main house envelope. Possibly use humidity controlled booster fan in a vent.

Option 2 – Supply only, positive pressure approach: Use one vent pathway only, for pushing conditioned air into the cellar (no exchange with the house). Humidity controlled in-line vent fan.

Asked By flitch plate | Sep 17 14
19 Answers

Liability insurance - what would that cover?

1. Does liability insurance cover issues related to removing improperly installed open-cell foam in an attic on the underside of a roof (i.e. all those horror stories about roof rot, or open-cell continually off-gassing or smelling weeks after it was installed, etc..)? Or is that a different type of insurance?

2. Should I specifically ask for the details in the Liability insurance to find out specifically what it covers, is that something contractors should be willing to share?

Asked By George G | Sep 12 14
2 Answers

Seeking underlayment material for exterior wall shingles.

I own a home built in 1965. It has cedar shingles as the exterior wall surface. I will be rebuilding a section of one wall as part of a project to replace a rotted window.

The problem is that the original construction includes a material that I can't find, and I'm not sure what could be used as a substitute.

Asked By Don Boettger | Sep 18 14
9 Answers

Most cost-effective method for achieving 3 ACH 50?

What are your strategies?

Asked By Nick Sisler | Sep 17 14
6 Answers

Tudor half-timber battens and exterior stucco — rainscreen assembly

Hi, I am having a house built in a Tudor style.
What are the effects of Tudor half-timbered battens on a stucco's rainscreen layer?

The lower half of the house will have a stone exterior.
The upper half will have a stucco exterior.

I have read the article “To Install Stucco Right, Include an Air Gap” and understand the importance of having a ventilated rainscreen gap in the stucco assembly.

Asked By Ani Brown | Sep 17 14
6 Answers

Has the Oak Ridge study on convective heat loss in blown fiberglass been updated to cover newer materials?

I'm evaluating blown cellulose vs. blown fiberglass (Knauf Ecofill). The Oak Ridge study is often quoted regarding the drop in R-value of blown fiberglass when the temperature differential is high. However the tested fiberglass density (.4 - 5 lb/ft^3) is much lower than the newer fiberglass.

Asked By Neil Weinstock | Jul 21 14
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