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9 Answers

Without natural gas, is there a better option than electric baseboard heat?

I am currently designing a home to build, that is to be the best compromise of sustainability and affordability. This home is 800 s/f and will have a passive solar heat design, and a wood stove to use our local biomass resource of beetle kill pine, however I need a third heat system for the house (what the City considers to be the primary system). Although natural gas is very cheap in CO, we decided we would rather put the money to run a gas line and install a furnace toward a net metering PV system, since we have the optimal climate for this.

In Mechanicals | Asked By Curt Lyons | Mar 7 14
12 Answers

Metlund D'Mand hot water recirculation pump

I am thinking about installing hot water recirculation pump to reduce hot water usage. Metlund D'Mand hot water recirculation pump seems to be a good choice since it's passive and does not use energy until you push a button when hot water is needed.

In Green products and materials | Asked By Rian Bart | Dec 2 10
5 Answers

Two layers of poly sheeting?

Would it be okay to put two layers of poly under a basement slab? The layers would consist of 4" of gravel, one layer of poly sheeting, one layer of XPS foam board, another layer of poly sheeting, and then the concrete slab.

Would this be beneficial or would it be overkill? I am building in central KY if that has any implications. Thanks for any input.

In General questions | Asked By Morris Farris | Mar 17 14
5 Answers

R-25 exterior rigid foam in Maryland, USA

I was given 50 sheets of 4x8 R-25 rigid foil faced foam that was left over from a commercial building project. I also have 35 sheets of 4x8 R-10 blue board. I live in Maryland just outside of Washington, DC. I plan to add an addition on to the house this summer. The existing house is all masonry with no insulation. I would like to use the 2" R-10 board to cover the existing brick section and them add cement siding and new windows,

In Green building techniques | Asked By James Eric | Mar 17 14
5 Answers

How to insulate/seal in tight spaces

Hi, I've got about 14" where the ground floor was bumped out 2.5" over the walkout basement. The joists run perpendicular, so there are about a dozen little "bays" roughly 30"x14" where the outside ir circulates and makes it feel like you're stepping on a slab ice in the kitchen above. I've caulked outside, but bridging fitted at the openings to the basement, along with various wiring runs and vents make it virtually impossibly to get a caulk gun or expanding tape into all the corners inside the bays.

In Energy efficiency and durability | Asked By Laura Braceland | Mar 17 14
1 Answer

Are we creating issues in single-family homes as we seal attic leaks and push the neutral pressure plane closer to the ground?

I just read Joe Lstiburek's article BSI-075: How Do Buildings Stack Up? and started wondering - are we creating issues in single-family homes as we seal attic leaks and push the neutral pressure plane closer to the ground?

In GBA Pro help | Asked By Gary Hamer | Mar 17 14
3 Answers

How to insulate a cathedral ceiling?

I am planning a deep energy retrofit of my home. I am located in Calgary Alberta. Climate zone 3a. Average winter temperature in Dec and Jan is -14c (7 deg Fahrenheit). But it can get down to minus -50f, and -20f is not unusual for extend periods of time during the winter.

In Energy efficiency and durability | Asked By David Richardson | Jan 3 14
6 Answers

Correct basement slab poly install

Getting ready to start a new home and have a few questions about the basement slab. I understand I need the gravel put down first, then XPS, and then vapor barrier before the slab. I keep reading about many different kinds of poly to use as the vapor barrier. I have found this poly and was wondering if it will be suitable? It is Grip Rite 10 mil clear poly sheeting, and it is made from virgin resins. I have also read that it must be black colored poly under the slab. Does the color really make a difference? Thanks for any input/suggestions.

In Green building techniques | Asked By Morris Farris | Mar 16 14
4 Answers

Looking for free or cheap heat loss software

I am looking for a free simple heat loss program so I can play around with various wall, window, floor assemblies? Any ideas?

In General questions | Asked By kye ford | Mar 16 14
10 Answers

Which way does the air flow within the house?

Might be an odd question but I have been trying to understand this for the longest.

With all the windows closed in my single-story house + basement, how can I figure out the direction of natural air flow. I assumed that due to stack effect, I would be able to locate those positive & negative air pressure differences to identify air infiltration/exfiltration.

In General questions | Asked By Jeff Watson | Mar 13 14
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