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5 Answers

Where is the humidity in my apartment going?

I live in a 680 sq ft concrete construction high-rise rental apartment in Redwood City, CA, with electric heat only, and I have a problem with dry air in the (fortunately short) heating season. I have to run my drug store vaporizer nearly 24/7 just to keep humidity over 30%. I go through several gallons of water a day, and my sinuses really don't like it when humidity goes much below 30%. This is crazy. Where is all that moisture going?

In General questions | Asked By Jacob Weel | Feb 24 13
11 Answers

Window installation with full-thickness masonry: planning for eventual replacement?

Basic question: what is the best way to design a window installation behind a masonry full-thickness veneer wall such that eventual window replacement is possible while maintaining the integrity of the drainage plane?

In Energy efficiency and durability | Asked By Andy Chappell-Dick | Feb 28 13
9 Answers

Looking for a cost-effective HRV or ERV system or design

Building in South Eastern Washington State. Very tight envelope. Using a combined HVAC System (ductless Heat pump and ducted) Thank You

In Energy efficiency and durability | Asked By Dan Easton | Feb 26 13
6 Answers

Packaged terminal heat pumps

I hear lots of talk about ductless minisplits but not much about packaged terminal heat pumps. Why not?

In General questions | Asked By erik olofsson | Feb 27 13
1 Answer

Air sealing and fire blocking PEX and PVC penetrations

What do I use to meet code-required fire blocking and good weatherizing/air sealing for the circumferential individual tube/pipe and ganged tubes (a cluster of tubes), penetration gaps for PEX-to-wood (and plywood) and PEX-to-PVC pipe, and for PVC-to-wood, and PVC- & PEX-to-drywall?

In General questions | Asked By Oak Orchard | Feb 26 13
4 Answers

Batt insulation

A while back I read an article that was talking about how batt insulation is not an air barrier. Air can just flow right through it lowering the R-vaule to almost nothing. A fact that I was already aware of. I got to thinking about underneath my own house, a vented crawlspace, I have insulation in between my joists that is exposed to air, without an air barrier on the underside of it. Is the R-19 batt insulation I have under my house preforming at a much lower value because the air can get through it? Please forgive my ignorance.

In Energy efficiency and durability | Asked By Matt Edwards | Mar 1 13
1 Answer

Minimum exterior foam sheathing thickness for a double wall design?

I read the article: http://www.greenbuildingadvisor.com/blogs/dept/musings/calculating-minim... and am questioning what R-value of exterior polyiso is needed to satisfy the moisture conditions in a double wall assembly: 2, 2x4 walls with 3.5" cavity in between. Zone 7/8. In a linear calc., I'd expect ~ R-30. Is this a correct assumption?


In Green building techniques | Asked By Matthew Michaud | Mar 3 13
0 Answers

Range hood recommendations for tight Canadian house

Any recommendations for budget island range hood that sucks 200 - 250 CFM or so that's available within Canada? I see some for $650- $850 here but in the US I've noticed some for $400 or so from AKDY. Any BC dealers? Most island range hoods would likely create a small tornado if there was any smoke with 750 CFM or more but I imagine with 6 speeds maybe one could find a less breezy setting. But why pay for all that extra power and wasted heat?



In Mechanicals | Asked By Patrick Walshe | Mar 4 13
2 Answers

How do I air seal a wall cavity?

I am looking for a cost effective DIY way to air seal the inside of a wall cavity during new construction. I am sure this has been written up someplace on this site, but I cannot find it.

In Green building techniques | Asked By Eric Heerdt | Feb 21 13
1 Answer

Steam heat questions

I purchased a home in Millinocket Maine and wish to have the most efficient heat possible. Currently there are steam radiators. I have a fan of Rinnai hot tankless hot water heaters and read they make "boilers". Would they work for "steam heat". Being a non-techinical person , I don't know and don't know what questions to ask.

In General questions | Asked By Kate Clark | Feb 23 13
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