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10 Answers

Foam insulation and vented attic

I am in the process of buying a house with open cell spray foam on the attic roof. The vents were left open for gas combusting furnaces. We are in Austin, Tx.
My budget to address the problem if there is one should be enough to cover any number of scenarios.

In Green products and materials | Asked By Heidi Hicks | Dec 16 14
27 Answers

B&G's low flow Vario ECM circulator - stupid efficient pumps

http://bellgossett.com/pumps-circulators/small-circulation-pumps-booster...

What I discovered as a result of the research stimulated by this GBA dialogue is that my circulator controlled hydronic heating will not work with a smart pump like the Alpha, Bumble B or the new Taco model.

In General questions | Asked By flitch plate | Dec 16 14
25 Answers

Foam-free builds

All the talk about sub-slab foam levels has me thinking. What floor systems easily allow foam free construction? Pier construction immediately comes to mind, but beyond that?

In General questions | Asked By Malcolm Taylor | Oct 4 14
6 Answers

Retrofit insulation of an exterior wall

I want to insulate my exterior wall and have the room gutted. I am in the Poconos of Pennsylvania and in Zone #5 I believe. I have 2x6 walls with Tyvek wrap, OSB siding and vinyl siding. The walls had R-19 faced fiberglass batts that were installed poorly. Currently all of the wall cavities and studs are exposed and are in perfect condition. The studs, tyvek and insulation have absolutely no moisture issues at all. They look like the day they were installed 22 years ago. I want to insulate but have questions about vapor issues. I sealed the rim joist with closed cell spray foam.

In General questions | Asked By John Divincenzo | Dec 17 14
7 Answers

Housewrap under vinyl siding

Ok, I'm getting educated and made some decisions. To recap, I'm residing with vinyl after stripping down to plywood sheathing (1/2" plywood over 2x4 studs, fiberglass batt, poly vapor barrier, sheetrock, zone 5). I've decided to go with 3/4" rigid foam over the plywood and under the vinyl which is R3 and very water vapor permeable. Can only fit 3/4" thickness insulation board (long story). Probably going to use Progressive Foam HalfBack H2O with water management system (grooves toward sheathing to drain any leaked in water). Want to add house wrap (Tyvek or Typar).

In General questions | Asked By george baloga | Dec 17 14
29 Answers

Any experience with an unheated (but insulated) slab as a finished floor? Will it be uncomfortably cold?

We are building a 1000 s.f. single-story home in Northwestern Ontario (climate zone 7) on a very tight budget. It will be well-insulated (walls R-40, roof R-60), and have triple-glazed windows, etc. An energy efficiency consultant calculated our heat loss as 16,800 Btu/hr at -32.8 F. The foundation is a short ICF stem wall with a 4" concrete slab (R-20 insulation underneath). Heating will be accomplished with the combination of a high-efficiency woodstove and electric baseboard, and we might add a mini-split down the road.

In General questions | Asked By Beth Turner | Dec 11 14
38 Answers

Heating with modulating condensing units

So far my looking into the use of a modulating condensing unit has left me with
the following;

They are high tech
They cost more than some older tech
They need good water with proper hardness and PH
They need a tech that is trained to maintain them
They do not condense if the return water is above 125 degrees.
Many install set ups include primary, secondary and what I call tertiary loops which to me add cost.

I can't understand how we go from $1000 to heat water to $8000 for all the parts for a fairly basic

In Mechanicals | Asked By aj builder, Upstate NY Zone 6a | Dec 15 14
7 Answers

Flow control valves for radiant floor heating

I have high efficiency house in central Vermont. It has radiant tubing in the floor for heat. I am trying to get the on demand hot water heater, a Takagi, and the circulator pumps to run as little as possible. Electricity is the biggest obstacle. The house is off grid with PV and batteries. Both are a little on the small side. The house has 6 zones with flow valves on each. No zone is over 400 feet. Tubing is 1/2 inch PEX. Current Delta T when three or more zones are open is 10 degrees. I currently have all flow valves wide open.

In Mechanicals | Asked By Jon Olson | Dec 16 14
6 Answers

Has GBA ever tested polyester fiber insulation made from clothing?

Has GBA ever tested polyester fiber insulation made from clothing? If so, what were the results and who makes it in North America?

Apparently, there is a huge push to use PET from recycled plastic bottles but little push to use recycled poly fabric. Some 75 to 80 % of Pet is used in fabric and it is largely going to landfills.

In General questions | Asked By Brian Timlick | Dec 16 14
4 Answers

Is Advantech better than plywood for subflooring?

My block and beam 1940's house had original tongue and groove 3/4 " pinewood floors in the original rooms of the house. This was the only floor. I've been checking around, and the best advice I've received is to use 3/4 Advantech over the original floors, before laying new 3/4" hardwoods. I believe this to be good advice, but is Advantech needed over regular plywood? And is 3/4" plywood needed over 1/2" plywood?

Thanks for any input.
NM

In Energy efficiency and durability | Asked By N Madrid | Dec 15 14
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