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1 Answer

Why can't I save the information I've found on your site?

I found an article on vermiculite in an attic and I want to print it for my client... How do I accomplish this?

In Green building techniques | Asked By Myrna Walker | Sep 9 15
4 Answers

Zehnder ComfoTube code issue

I am an architect working with a contractor/homeowner who is currently building a new home for his family in St. Paul, Minnesota.

He has installed a Zehnder HRV with associated Comfotube piping and insulated air intake and exhaust according to Zehnder's layout and specification. However, our HVAC inspector will not approve the system as it does not meet their ducting requirements - it is not UL listed nor is it a type 0 or type 1 assembly.

In Building Code Questions | Asked By L Alm | Aug 5 15
5 Answers

How to use rigid foam insulation in roof space

Context: Central Pennsylvania. Want to convert vented (sofit and ridge vent) cathedral attic space into conditioned space. No plans to replace the roof. Roof cavities are 7.25". Cost is important, but so is DIY-ability.

Plan so far: Cut and cobble XPS into cavities between trusses, sealing all the way to exterior wall. Assembly stack spray foamed in place:
1.25” ventilation
2 layers of 3” XPS
1.25" ISO on inside face covering roof trusses

In Energy efficiency and durability | Asked By Mark Sentesy | Sep 9 15
6 Answers

Unvented roof, Zone 3B, foam-free

Hi Martin,

First off, I have read a wealth of articles on the subject of unvented roofs, by yourself and Joseph Lstiburek. I started with your “How to Build A Cathedral Ceiling” article and read pretty much everything related to this from you and Lstiburek. The conclusion being that for an unvented roof you either install closed-cell spray foam between the rafters, or rigid foam above the sheathing at a thickness dictated by your climate zone to keep the sheathing warm enough.

In GBA Pro help | Asked By Joe G | Aug 26 15
1 Answer

Insulating existing barn with board and batten siding?

Hello,

I have an existing post and beam barn in Massachusetts that my wife and I would like to convert to a workshop/studio space. It's clad with existing rough cut vertical pine siding to which I plan on adding vertical battens to seal it up better.

I would also like to insulate. Preferably with Icynene to get a tight seal and discourage rodents from nesting in the exterior cavities. The Icynene dealer suggested open cell and said that a weather barrier isn't necessary(?)

In General questions | Asked By Evan Halstead | Sep 8 15
2 Answers

How long will closed-cell polyurethane foam retain its greater-than-5 R-value?

The laws of physics and thermodynamics state that a stable R-value higher than about 5 is impossible to achieve when using air as the trapped gas in an insulating material due to the thermal conductivity of air itself. Most materials using air will be lower than than due to the thermal bridging of the structure itself, which is why EPS has an R-value that tops out in the mid 4s. XPS, polyiso and polyurethane boast higher R-values than this because the trapped gas is not air, but rather, some blowing agent with a lower thermal conductivity than air.

In Energy efficiency and durability | Asked By Nate G | Sep 8 15
2 Answers

Why would someone buy a heating (gas fuel) and cooling package unit?

Hi!

I recently moved to CA and have started seeing a lot of homeowners installing heating and cooling package units, usually installed on the roof. These systems are gas-fueled, with a max AFUE of 81 or so. Why would someone buy one of these units instead of a full Air Source Heat Pump to do heating and cooling?

For example: http://www.lennox.com/products/packaged-units/LRP14GE/

Thanks for your help!
Whitney

In Mechanicals | Asked By Whitney Larsen | Sep 8 15
6 Answers

Cavity insulation with exterior rigid foam

I'm looking for advice on stud cavity insulation. Walls will be (from outside in) LP smartside lap siding, 3/4" rainscreen gap, 6" EPS foam (R-24), self-adhering vapor/water/air barrier, OSB, stud cavity, then interior wall covering which will be either T&G pine or drywall with latex paint. My main floor walls are 2x4 and the basement walls are 4' below grade ICF and 4' above grade 2x6. I live in zone 7a - eastern North Dakota.

In Energy efficiency and durability | Asked By Adam Emter | Sep 5 15
2 Answers

Is closed cell foam insulation worth the cost for a 75 year old home with 2x4 exterior walls?

I am remodeling my 75 year old home. I am gutting the interior walls and adding a full dormer. The exterior walls are 2x4. Is it worth the cost for closed cell foam insulation or is a traditional fiberglass insulation sufficient? Thanks, Paul

In Energy efficiency and durability | Asked By Paul Hanson | Sep 6 15
9 Answers

Improving hot water heat pump tank efficiency with free dryer heat

Hi. I have been thinking about how to improve my GE electric hot water heat pump efficiency, particularly in the winter months. It is located in a very well insulated utility room off the garage (larger than recommended minimum volumes). The by-product of using the heat pump is cool, dry air, which in turn creates a cold room calling for accessory heat to warm the room back up to temp for the heat pump to then work efficiently again. I find the room temp is fluctuating up and down in conjunction with the use of heat pump this not making it as efficient as it could be.

In Energy efficiency and durability | Asked By Matthew Michaud | Sep 7 15
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