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2 Answers

Windows installation over foam board

Going to be replacing siding and windows and am planning on installing 1" rigid foam board over sheathing. My main question is with installing the windows, can they be installed directly over the foam board or should I picture frame out around the opening? Or I guess the right question would be what is the best way to install over 1" of rigid. Thanks.

In Green building techniques | Asked By Chris Wollberg | Dec 27 12
2 Answers

Condensaton and icing on new E-Star windows

Hello, I have a new house (under 1 year old) that is E-Star compliant with double-glazed thermopane casement windows. Now that the weather has turned colder I am seeing condensation and icing along the bottom of the interior (room) side of most of my windows. The humidity in the house is pretty low. Is this indicative of defective windows, and how can I make a more accurate determination?

Thanks in advance,

In Energy efficiency and durability | Asked By Edmund Nadolski | Dec 26 12
10 Answers

Sketchy insulation contractor

After many months of research (thanks to this site) I finally hired an insulation contractor for my attic. The contractor was certified by building performance institute and after 4 different estimates I was pretty confident I had selected the correct one.

In GBA Pro help | Asked By Rocky Pembroke | Dec 22 12
7 Answers

Portland cement?

HI, I have been reading about Portland Cement and was wondering your thoughts. It had been written that it can cause fatigue from standing on it as it draws out the energy just like it can drain a car battery. Also has been known as "new barn" syndrome for animals. German employers actually cut out the cement where their employees stand and put a different product to not cause the fatigue.

In General questions | Asked By Kami Kline | Dec 22 12
6 Answers

When does a new boiler installation legally need a service visit?

Hi guys, Im desperate to find out for my pensioner mum when a new boiler installation legally needs a service. The boiler was installed incorrectly and was checked by another boiler installation company 2 and half years after installation who said that if she hadnt had it checked when she did it could have been deadly. Myself and mum didnt think a brand new boiler installation would need a service for at least the first 2 yrs ( a bit like a new car). Can someone please tell me how long "legally" a new boiler installation needs a service.

In General questions | Asked By angie brook | Dec 22 12
6 Answers

Flash and batt insulation

I have a 100+ year-old home in climate zone 6A (Wisconsin) that needs new sheathing and siding, so I figured I may as well reinsulate the wall cavity as I pull and replace the sheathing (currently has R13 batt in a 2x4 wall cavity). After considering a variety of options, I keep coming back to flash and batt and wonder if this will work for me. Most (all?) flash and batt applications are applied from the interior--that is, 1-2" of closed-cell spray foam is applied to the exterior sheathing, batt insulation is installed, and drywall is put up.

In GBA Pro help | Asked By Eric Rinehardt | Jul 27 12
15 Answers

Locating an HVAC condensate drain in a Passive House

What is the best approach for dealing with condensate drains in a Passive House?

We will have 3 mini split cassettes on the main floor and one for the basement for the Passive House we are building in Maine. See our blog at www.EdgewaterHaus.com.

Options we have considered so far:
- Standard local practice is to bundle the condensate drain with the refrigerant coil and control wires directly outside. Unit drains in summer A/C, not in winter heating so no freezing concern. We don't like this approach because the condensate tube is an air pathway into the house.

In PassivHaus | Asked By Roger Normand | Aug 23 12
1 Answer

How to heat indoor pool and combine with dehumidifier?

To build a small indoor pool, about 12'x16'x4', I need to dehumidify the space and heat the pool water. I would like to combine the two functions with a heat pump that uses hot attic air, feeds the pool heat exchanger and a dehumidifier, hopefully I can use the condensed the output from the dehumidifier to dump it into the pool for an extra bonus. What components should I buy? Thanks for any suggestions!

In Green building techniques | Asked By Johannes Notthoff | Dec 21 12
1 Answer

Rim joist insulation

I have several questions about insulating the rim of the 1st floor platform above the basement of my 2001-built house. I have recently found condensation on the rim joist after cold nights under the squares of the open-faced FG bat that had been shoved between the I-joists. I removed the FG and no longer get condensation, but would like to reinsulate effectively.

I plan on installing rigid foam between the I-joists, and need to determine what R value is appropriate for Northern Colorado.

In Energy efficiency and durability | Asked By William Fryer | Dec 21 12
28 Answers

Larsen truss questions

Hello. I was hoping to get some more feedback from the GBA folk.

We have just framed a small house in an area with a -32 design temperature. our plan is to attach a Larsen truss to a conventionally framed wall. the wall detail is as such: 2x4 stud wall, sheathed with 5/8' t+g OSB, 8"-ish Larsen truss, cross-strapped with 1x, rainscreen, cedar siding. we have to use batt insulation because dense-pack or wet-pack cellulose is not available (we will use blown cellulose for the attic).

In General questions | Asked By erik olofsson | Oct 3 12
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