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41 Answers

Best way to have a wood fireplace?

We are building a custom house, and are nearing our final planning stages before bids with our architect. We are planning to have a wood fireplace on the ground floor, within the building envelope. When it is burning, it will likely to burned with any glass doors on the fireplace open, for aesthetic reasons. It is only going to be used as a heat source as an occasional backup. What are the best ways to minimize the energy problems of an wood fireplace? It'll probably be a zero-clearance type of fireplace. My husband will not agree to a gas or wood stove, so don't even suggest it!

In Energy efficiency and durability | Asked By Clara Kim | Feb 22 15
9 Answers

Foil-faced batt insulation effect on wall construction?

I’m in the process of planning energy retrofit for my house located in Philadelphia (zone 4A)
Existing wall construction consists of t1-11 over 2x4 framing with foil-faced batt insulation. The plan is to add 2 layers of 2” polyiso to the exterior taping joints making polyiso my WRB. Is there any concern that moisture trapped in the wall cavity won’t be able to dry to the interior due to foil faced batt insulation?

thanks!

In GBA Pro help | Asked By Michael Kalustov | Feb 27 15
5 Answers

Dense packing cellulose - height of cavity

What are the thoughts out there on how tall a cavity in this double stud wall can be before there are concerns?

Here's the wall:

There's an outer 2x6 wall, 16" O.C., and an inner 2x4 wall also 16" o.c. There's a 6" space between the inner and outer studs, for a cavity depth of 15".

The first floor walls are 9' tall, with an 18" deep floor truss above. In other words, there will be a 10.5' height of cellulose. The second floor is about 8'4".

In General questions | Asked By Graham Fisher | Feb 28 15
4 Answers

Sturbridge, Massachusetts — electric boiler

Sturbridge, MA. Have abundant PV, similar to Ed Jones' question. Need electric boiler recommendations. 40 panel ground mount lease. Put in at the height of recent depression. VG deal.

Property has small slab, under 900' sqft,, 3'' foam under and sides. low e glass, 2x6 walls.

Have abundant solar PV, no electric bill, even this winter. I do clean the panels after storms.

Current fuel is wood, we do not need to discuss.

I would rather use up more solar electricity, instead of sell it back to the grid.

In GBA Pro help | Asked By howard kelley | Feb 28 15
4 Answers

Multi split with ceiling fans?

I am looking into a multisplit heat pump system for our deep energy retrofit project. We are used to leaky homes with ceiling fans in all bedrooms while sleeping. We find the moving air to be very comfortable while sleeping. In fact we noticeably miss the fans when traveling even when there is a dedicated Hvac like in a hotel room. In general, is the modern usage of the term 'comfort' (meaning stable temperature and humidity) consistent with our desire to feel the lightly moving air when sleeping?

In Mechanicals | Asked By alok khuntia | Feb 27 15
4 Answers

Insulation question

I have an apartment want to add insulation from the exterior.
It is a block building 1950's vintage. Walls in the inside are stripped with 3/4 furring strip. Insulated with 3/4" fiberglass with vapor barrier on inside. Finished inside with plastered walls.
I am thinking of adding foam sheet insulation to the outside of the building. I do not want to trap in moisture and cause mold problems. .
What is the proper way to do this. I do my own work. If anyone can guide me in the right direction I would appreciate it.

Thank You,

In Green building techniques | Asked By Charles Craig | Feb 24 15
12 Answers

"Pretty good house" window choices

Hi, we are in the design stage of a high efficiency retrofit and addition to an 1888 Victorian house in the Chicago suburbs. Our architect and his preferred builder are leading many of the Passive house projects in the area and are very interested in getting our project to approach those standards. Although i think it would be very cool as well, i am finding that the technical approaches and costs simply don't justify the benefits. In doing my own research, i am leaning towards designing for "pretty good" near net-zero instead of near-passive.

In Green building techniques | Asked By alok khuntia | Feb 27 15
2 Answers

How to properly vent a modfied gambrel roof?

Hi,
My family and I purchased a 2 story modified Gambrel style home 5 years ago. By modified, I mean that the vertical roof sides go all the way to the foundation. So we have sloped interior walls upstairs and downstairs.

In Green building techniques | Asked By Charlie Baxley | Feb 23 15
5 Answers

I'm converting a barn to a residence

The slab is not insulated, and there are no below-grade details beyond the posts that support the structure. My architect is resistant to insulating on top of the slab. He worries that if I don't leech heat into the soil...

The slab is 64' x 46', and 4" thick. The central section was tapered toward center drains, so we have some leveling to do. We are in zone 5, I believe, and temperatures have recently dropped to -18F, though that is unusually cold. My concerns are comfort as well as avoiding condensation that might degrade floor coverings and encourage mold growth.

In Energy efficiency and durability | Asked By Dean McCracken | Feb 25 15
4 Answers

PERSIST in South Florida?

this question is for those familiar with PERSIST style building techniques.
I am considering building a home using PERSIST construction instead of CBS construction in south Florida.
(1) Does anyone know if Grace IWS would effectively stop termites?
(2) would exterior stucco be sufficient in protecting XPS from deterioration and infestation?

In Green building techniques | Asked By John B | Feb 26 15
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