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2 Answers

Most cost-effective method for achieving 3 ACH 50?

What are your strategies?

Asked By Nick Sisler | Sep 17 14
18 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
12 Answers

I'm wondering if you can insulate the attic roof rafters

Thanks everyone for your insight. I think the thing I've learned is that if your not going to finish the attic area and the walls to the finished room are insulated you don't have to insulate the roof joist, but you do need to insulate in between the floor joist and the finished walls.

In our doormer, There are two small doors going into the attic area from a finished dormer area, and the walls that are finished have batting. The floor joist in the attic have old blown fiber glass that has settled, so we need to fluff it up or add to it.. Thanks so much everyone.

Asked By kristin burton | Sep 12 14
7 Answers

Better choice of exterior wall construction for new home?

We're building a new home in central Iowa. We're in climate zone 5. We thought we had a final above grade wall spec. Now, we're entertaining a different one. I think the first one is more robust, but I'd like an opinion on the two walls:

Wall 1 from inside to out:
1/2" drywall with latex paint
MemBrain "smart vapor retarder"
2x6 wood stud, 16" o.c.

Asked By Silas Hoeppner | Sep 16 14
4 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
1 Answer

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
26 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
12 Answers

Should my indirect hot water heater have a mixing valve?

I have a 2300 square foot colonial, built 1960 in Massachusetts (Zone 5A), with three zones of fin tube baseboard. There's a 75 gallon whirlpool tub which we almost never use; the two showers are fairly low-flow. Heat loss done by Comfort-Calc.net was 55,840. I use town water, which is very good quality (Quabbin reservoir). I've accepted a bid to replace my heating system with a Lochinvar WHN-85 boiler and SIT40 indirect water heater.

Asked By Daniel Griscom | Sep 15 14
7 Answers

Options for air sealing T&G ceiling with no air barrier installed

Hello all,
I apologize if this question appears a repetitive one, as I have read through a good bit of the Q&As here, but still cannot determine my best course of action.

Asked By Rob Leonard | Sep 14 14
5 Answers

Effectiveness of Roxul "flash and batt" - irregular closed-cell spray foam causing air gaps?

I have a spray foam crew coming Thursday to convert my attic to "unvented" (2x8 rafters). They want customers to do 5". My plan though was to do 4" and then 3.5" Roxul batts to fill followed by a layer of the Roxul board to reduce bridging on the rafters.

Asked By Chuck Swanberg | Sep 16 14
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