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3 Answers

Provide make up air for a wood stove

Make up air

In Green building techniques | Asked By Thomas Williams | Oct 5 13
3 Answers

Concrete slab

I have a 1,000 sq ft concrete slab with copper tubing inside. Live in cold climate. To complicate matters, the interior walls are are poured concrete. I'm thinking of switching to baseboard heat with 1" rigid foam onto of the slab then plywood on top of the foam and then flooring.

Not sure if the concrete walls will be a problem with this approach ?

I would consider having the old radiant heat copper tubes tested, but I've heard that since it was built in 1950 they may not last another 50 or so years.

Any thoughts?

In Energy efficiency and durability | Asked By dan scott | Oct 10 13
5 Answers

Best approach for attic insulation?

I recently moved in to an early '70s Colonial in zone 5. The attic is poorly insulated with a couple of inches of loose-fill that looks like fiberglass.

The attic has newer AC (not heating) equipment, including an air handler and some flexible insulated duct on the floor (not suspended). It's also poorly ventilated, with 2" ventilation grilles in the soffit about every 10 feet, no ridge vent, a gable vent on one end and a small vent in the roof on the end opposite the gable vent. Finally, the asphalt shingle roof is in decent shape but approximately 17 years old.

In General questions | Asked By Andy Martin | Oct 9 13
3 Answers

Best way to insulate PEX attached to subfloor on new home?

Building new home. We are installing infloor heat in our basement (cement) and the basement will be fully finished. We are also installing floor heat for a main level (ranch home), attaching the pex to the bottom of the subfloor. Wondering what the best method for insulation (if any) is required.

We will have open web floor trusses. Basement ceilings will be fully finished. Thanks in advance

In General questions | Asked By keith schmidt | Oct 3 13
3 Answers

Everything at GBA is "Green Pro"?

Hey guys, I have no access to any story in the newletter as if it's all pro. John jnmbailey@comcast.net

In Webinar Follow-up Q&A | Asked By john bailey | Oct 9 13
1 Answer

SIP roof details

I have read a lot of what is already on GBA forums, but I could not find answers to a few questions.

I live in northern Minnesota (Zone 3 = can be very cold!) and am building my first home, SIPs over timber frame. I am preparing for a standing seam metal roof and I have three questions about roof detailing.

In Energy efficiency and durability | Asked By LynnAnne Vesper | Oct 10 13
1 Answer

Is it OK to have an unvented attic?

My attic was recently insulated with spray foam insulation, and it is now an unvented attic. Are there any concerns I should be aware of with this system? Do the benefits outweigh any potential risks? What are the pitfalls?

In General questions | Asked By adriana mcgarity | Oct 10 13
1 Answer

Adding 2" foam to exterior of building - window trim detail?

Looking at a job: old farmhouse, solid wall construction, rough sawn 2x12 installed vertically.

Will be removing siding, adding 2" foam to exterior.

Windows have replacement low-e windows. Will remove window trim.

Looking for ideas on window trim (PVC detail).

In Energy efficiency and durability | Asked By Mark E Thibault | Oct 9 13
9 Answers

Confirmation of manometer outcome

I am looking to get a ball park estimate of the cfm of a range hood exhaust in a restaurant. I saw that to do a bathroom exhaust fan you create use a flow hood with a certain size hole. Instead I am going to use the building as the "flow hood." I am going to measure the pressure differential between the outside and inside with no fan running. Then I am going to turn the fan on and measure the pressure difference. If I subtract those two outcome it will give me Pa. of the exhaust hood. Then, based off of a trusty YouTube video, the formula to convert the Pa.

In General questions | Asked By Matt Edwards | Sep 26 13
1 Answer

What is an appropriate sized minisplit head for a 27'x32' basement with four 32"x12" windows in zone 4A (Long Island, NY)?

I will be insulating the top ~1.5 ft. that is above the foundation to R-15 but the cement block foundation walls will not be insulated until the basement is finished sometime in the future. For now, this area will only be used for laundry and storage but will be a play room in the future. I received a proposal for a 12000 btu unit but from what I've seen from online calculators, this may be too little. Any advise would be appreciated. Thank you.

In Energy efficiency and durability | Asked By Kevin Schramm | Oct 8 13
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