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2 Answers

I am looking to use a detail similar to 4-05055 - metal roof/unvented/cathedral/exterior 4.5" rigid insulation. I have a few questions on the assembly:
1- are the layers of rigid insulation adhered together?
2- what type of fasteners are being used to go thru the first layer of sheathing, thru 4.5" insulation, 2nd layer of sheathing and into rafters? spacing? (I am located in NY - 90 mph ground wind)
3- do you know a relative comparison between this detail and using a SIP panel - cost? installation? structural?

Thank you!

Asked By Linda Zwart | Jul 23 14
1 Answer

This question might have an obvious answer, but I haven't been able to dig up anything on google. If I were to purchase a tear-down property that had an existing uninsulated, fieldstone basement, what would be the best course of action to build a high performance house? Fill it in with dirt then to then create a slab on grade? Tear out the fieldstone and use the existing cavity to create an insulated basement (while also hopefully re-using the fieldstone on site for something useful like a wall)?

Asked By Ethan Fahy | Jul 21 14
14 Answers

Hello,

I'm looking to pour a basement slab as follows:

6" washed 3/4" stone- compacted
2" XPS
vapor barrier

Next I'd like to tie the PEX to mesh and pour. That's the problem. Masons hate this, PEX can get cut when control joints are cut. Chairs holding up the mesh just get crushed or are a trip hazard.

If the PEX is attached to the foam, not thinking you can put the vapor barrier over the foam / PEX, plus the PEX is under 4" of concrete, and I understand it should be within the 4" of concrete.

Seems this very point is a sticking point in the overall theory.

Asked By Ted White | Feb 23 14
3 Answers

Hi All,

We are using Foamglas for insulating under our slab as well as the slab edges (monolithic slab on grade). It is a requirement to leave a 2" gap above the Foamglas on the slab edges for termite inspections. Are there any options to satisfy this requirement, but not have the thermal gap? Perhaps industrial strength velcro or something :) ?

Thank you,
Stacey Owens

Asked By Stacey Owens | Jul 18 14
4 Answers

I have a weirdly designed house.

The attic in the lean-to addition has 2x6 joists (actual 2x6 - old wood). The joists sit directly on top of the wall framing for the ouside wall, and extend outward from there. They're notched to sit flat on the outside wall header. - there's less room for insulation there, as teh joists are no longer the full six inches.

There was never any room for both insulation and ventilation, so we have a 'hot roof'. It was created using three sheets of XPS foam sandwhiched together, and sealed with copious amounts of canned sprayfoam.

Asked By Anders Ufland | Jul 15 14
17 Answers

I am not in construction or an architect, just someone who would like to live in/build a small, comfortable, energy efficient home. I don’t need and could never afford a Passive House. Don’t even know if one would work where I live. I live in the low desert southwest near Phoenix. Living is very different here than in cold weather areas. And very different than Florida or humid areas of Texas. Outside temps over 100F in shade 5-6 months; highs 115F; nighttime lows 95F for at least 2-3 months. Low humidity 10 months. Little or no drought resistant shade trees.

Asked By Anneal G | Jun 27 14
1 Answer

The cathedral ceiling roof assembly on a recent addition to my house consists of vented fiberglass-filled bays with with an interior layer of 1/2" foil-faced polyiso under the 2x10 rafters.

Investigating a strong odor on hot days, I found that the builder...

Michael Roland,
Nassau, NY

Asked By Michael Roland | Jul 16 14
2 Answers

We are in a 5A climate zone, near Chicago. We wanted to add a retractable pool enclosure up against an existing house that would be used year round. http://www.libart.com/evolution-lean-to-structures

The existing house has a wall construction what has fiber cement siding, 1" rigid insulation with taped seams, Tyvek, 5/8" plywood, 2x6 framing with open cell insulation and drywall on the interior. See attached image. Keep in mind that this wall was build 9 or so years ago.

Asked By Nathan Kipnis | Jul 11 14
4 Answers

In a conversation with a tenant earlier today....

The tenant (a PHD Cello student) had visited Israel last summer. When Green Building came up, he commented that ALL houses in Israel have Solar Hot Water Tanks installed. Ok, I will presume he is off by 50%, still 50% vs .....how many in the USA.....less than 00.1% as a guess. [And I doubt he toured many rural areas vs metropolitan.]

So my question is, what are we doing wrong...or what are they doing right. Yes, I realize the climate is different. Is it the laws, the need, the desire, or is is technical!

Asked By John Granoski | Jul 12 14
1 Answer

We are replacing a roof structure on a portion of our 1832 timber frame home with regular framing (17' x 20'; 20' is horizontal roof span). Due to the 4' kneewall and 5 pitch roof, the ceiling height in the peak of the room is only 8', so we want to retain the cathedral ceiling in this large room. We are using a laminated 14" ridge beam and 2 x 10" rafters (16" OC), with no rafter tails (maintaining the original structure design with the timber frame). We are climate zone 5, Marine (SE Michigan, between the big lakes).

Asked By Emily Rusnak | Jul 12 14
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