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14 Answers

In search of an airtight ceiling, I have heard talk of sheetrocking the ceiling & dropping in a 'second' ceiling

In search of an airtight ceiling, I have heard talk of sheetrocking the ceiling and then dropping a 'second' ceiling where lighting and maybe HRV ductwork etc. could be installed. I am wondering how this was accomplished.

For my home I plan to build, a nine foot ceiling in a one story home with trusses, plastic barrier and then sheetrock attached to the trusses. Are 2 x 4's hung down about six inches with some kind of joist hangers, and another layer of sheetrock installed with lighting and HRS ductwork in between?

In Green building techniques | Asked By Steve Vigoren | Feb 13 15
6 Answers

How do I construct a brow roof on the first story of a two-story structure?

See attached file photo. I can find all sort of plans for different brow roofs with the exception of the one in the attached photo. That photo is titled the Stanton House with overhang and credited to Martin Holladay,

In GBA Pro help | Asked By Steve Skalski | Feb 14 15
1 Answer

How come some questions are answered by D Dorsett and others by Dana Dorsett?

Are they the same person?

In General questions | Asked By Alan B | Feb 15 15
1 Answer

Foaming EPS slabs on roof

Planning on a timber frame with 2 layers of 5" eps, staggered joints over cathedral ceiling. This will have 2/4 sleepers on top of eps running up roof for a vented roof. I am concerned about using canned foam between joints as I have been reading about shrinkage, settlement of frame, etc. causing foam joint to crack. Any thoughts or experience using something like foam sill seal between joints? Roll it out along edge of slab, slam next slab against it. Should be flexible enough to move with the house. Any suggestions on a better product to use?

In General questions | Asked By John H. Stehman | Feb 14 15
2 Answers

Can I replace open-combustion HVAC in my attic with a sealed-combustion unit?

Bought a house in NH a few years back and it has gas furnace in attic and i am tired of heat loss, constant running, and melting snow! After I limp the house thru the rest of this winter i am going to explore spray foam insulation (prob close cell so i don't have to deal with vapor barrier etc) and i cant with current furnace. The furnace is 20 yrs old and seems to fire/cycle all night long. The ducts and everything is also in attic. Can i replace this open combustion (or un sealed or whatever the term is) furnace with a sealed unit? Does the returns and ductwork have to be changed too?

In General questions | Asked By Andy Giaconia | Feb 14 15
7 Answers

I keep seeing descriptions of Passivhaus buildings using 90% less heat

But what does this equate in in btus at peak load or kWh/yr?
I know this is a broad question thats different in every climate but i just want some numbers for context, so lets compare two code minimum houses @1000sq/ft, one in climate zone 5 with 4000HDD and the other in climate zone 6 at 5000HDD compared to two identical location passivhaus'
For the sake of argument lets say both buildings have a design temp of -25C


Can these numbers scale with size (would they double at 2000sq/ft or be half at 500 sq/ft?

In PassivHaus | Asked By Alan B | Feb 14 15
10 Answers

Slab on grade questions

I am looking into purchasing a home built in 1973 and want to make sure I do my homework prior to taking the plunge. The garage and den are both at ground level on a slab. The rest of the first floor is built above a crawlspace. The den currently has carpet but I would want to replace it with laminate or wood flooring. Do I need to be concerned about moisture coming through the slab? Is there a way to tell if the slab has a vapor barrier or insulation underneath?

In Energy efficiency and durability | Asked By Daniel G. | Feb 10 15
6 Answers

Attaching rigid foam... with tape?

To attach rigid foam to a concrete wall, most people seem to prefer screws, plastic anchors, or adhesive. Is it possible to simply use tape instead? It could be rolled up into loops to form a double-sided tape loop that has some allowance for irregularities in the concrete (these would go on the back of the foam), and perhaps the side edge could also be taped to the wall with a folded "L" piece of tape, before the next piece of rigid foam is put up.

In Green building techniques | Asked By Nick Welch | Feb 13 15
6 Answers

Insulating Basement in Flood Plain

Hello, my wife and I purchased a flood damaged house in our home town last year. The flood was three years ago and resulted in four feet of water in the first floor. It was considered a 500 year flood, before this the house had never seen water in the first floor in it's 60 years, though the basement has flooded multiple times. We've restored the first floor to that of a normal house and I'm now looking at two areas to work on: my desire to have a basement hangout and weather proofing. I figure the best place to start is where the two meet.

In General questions | Asked By Joseph McGrail | Feb 13 15
5 Answers

LED Filament bulbs

Does anybody have any experience with these new so-called LED filament bulbs?

In Green products and materials | Asked By Aaron Birkland | Feb 2 15
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