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11 Answers

Air sealing and insulation question

I am buying a 1900 bungalow in the white mountains of NH, 10 foot ceilings 4 inch walls. The only insulation now is the attic is capped. The heating is hot air, with unsealed or insulated duct work. The house is one story. We are closing in October, so I'll have no access until then. Where should I start?

In General questions | Asked By Ken Chester | Aug 12 14
1 Answer

Make up air for clothes dryer; exhaust only system

In new construction with an exhaust only ventilation system, is there a need for a make up air source for an electric clothes dryer. I am toying with the idea of some supplemental passive air sources...

In Mechanicals | Asked By Robert Holland | Nov 19 14
7 Answers

My wife needs convincing ...

You all have me convinced that I can change out my Mitsu AC minisplits with some all season heating and AC cold climate heat pumps and save substantially on the energy costs over my 98% efficient boiler.

But my wife is not convinced.

In General questions | Asked By flitch plate | Nov 18 14
1 Answer

Rim joist insulation

I insulated and air sealed my rim joists using 2 and 3/4 inches of polyiso along with one part foam around edges plus an inch or a bit more of mineral wool to get me to my target of R20+. I covered the insulation with 1/2 drywall for a thermal barrier and caulked the top and side edges as well as around plumbing penetrations through the drywall. I did not caulk the bottom edge (at least as of yet) as it is hard to get a caulk gun to the area. This edge is screwed tightly against the sill plate. Given this construction, do I have any condensation issues to worry about? I live in zone 5 (NH).

In Energy efficiency and durability | Asked By Michael Lee | Nov 19 14
4 Answers

What do I do about my backdrafting oil-furnace?

Last weekend after noticing my bath fan wasn’t working. I went into my attic to see what was going on. I found the vinyl flex duct that was snaking across the attic floor full of water, so I swapped the fan for a high-quality model and did a nice job running 4-in. aluminum pipe to the outside. The fan is rated at 70 cfm and now my bath doesn’t fill with steam and my windows are no longer fogged up in the morning.

In Mechanicals | Asked By Patrick McCombe | Nov 19 14
0 Answers

Masonry tie/anchor between concrete wall and stone facade

I am looking for a masonry tie that limits thermal bridging between concrete wall and natural stone or brick facade. The planned wall assembly looks like 6-8 inch structural concrete, 7 inch rockwool insulation, 3/4 inch air gap, 4-6 inch natural or engineered stone facade.
There a wall ties from German manufacturers that reduce thermal bridging. The product is accord to the German DIN Norm and has CE certification that is valid in the EU and Scandinavia.
Are there US product that I am not aware of or is there an inexpensive way to get the foreign products approved by an inspector.

In Green building techniques | Asked By Andreas Ryll | Nov 19 14
4 Answers

Unvented roof underlayment choice

My questions are related to part of the reply Mr. Holladay made to the "Proper Underlayment for Unvented Asphalt Roof" question posted on 11-14-14.

In General questions | Asked By Roger Berry | Nov 18 14
1 Answer

Is there any low- or no-VOC, mold-resistant sheetrock and wall plaster on the market (for basement reconstruction)?

It is my understanding that sheetrock and wall plaster are typically high-VOC items, especially mold-resistant sheetrock.

Also, are carpet tiles a good low- or no-VOC flooring option?

In Green products and materials | Asked By Nathaniel Strosberg | Nov 18 14
9 Answers

Improving the airtightness of an average entry door

It's been cold this week, and I'm fighting drafts around my doors. Most doors have the same air sealing method, involving a foam kerf seal. It's an inexpensive and robust design. (Remember the Stanley magnetic seals?- those were tight, but made of conductive steel). http://www.homedepot.com/p/Frost-King-E-O-1-in-x-7-ft-Brown-Replacement-...

The problem is that the door is not held tightly enough against the seals. But if you use the deadbolt to hold it tight, the deadbolt can be difficult to operate, and it will wear out faster.

In Energy efficiency and durability | Asked By Kevin Dickson, MSME | Nov 17 14
2 Answers

Am I crazy or is the NIST house really confusing?

I was all excited to dig into the details of the NIST NZERTF. I was slowly moving away from SIPS and looking a lot at the PERSIST building method. I was reading articles on the building science center's site about the "perfect wall". All standard building science nerd stuff. Then I get onto the NIST site and click on the "centerfold", the Fire, Plumbing, Mechanical, and Electrical Plans PDF. I started scrolling though the pages and reading all of the details. What should have been a good time went south pretty quick. Looking at DHW I see a HPWH.

In General questions | Asked By Joseph Welker | Nov 18 14
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