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1 Answer

Zone 2 wall insulation code

Was reviewing the IRC for insulation requirements for zone 2. Wood frame walls at 13 and mass walls with exterior foam at 4. Why the difference? And this brings up the real question which is: I'm about to put rigid foam on the exterior of a single story block house......any idea what the r value I should shoot for before reaching the point of diminishing returns?

Asked By Robert Brown | Feb 5 15
4 Answers

How to insulate a cathedral ceiling under an exposed metal roof?


Asked By Jennifer Duffy | Feb 2 15
9 Answers

Help to plan foam insulation with AC ductwork inside 4 1/2" high rafter bay cavity in roof assembly.

Our house was built around 1850 and has no insulation or air sealing in the roof. The finished attic has a partial cathedral ceiling, and the high velocity 4" AC flex ductwork runs from the air handler which is located behind a kneewall in the attic, up one side of the cathedral slanted ceiling (7ft), across the flat part of the ceiling (about 10ft), and partially down the other side of the slanted ceiling, through rafter bays which are only 4 1/2" deep, due to the very old house construction. Ceiling material is plaster lathe.

Asked By James Berry | Feb 2 15
2 Answers

How to insulate valleys in a cathedral ceiling to avoid ice dams?

We're in a maritime climate on the west coast of Newfoundland, Canada. Climate is zoned as 6 but we have mild winters with averages around -10 C. We get warm spells followed by cooler days, not your average climate 6 winter.

Asked By OLIVIER van lier | Feb 1 15
11 Answers

LPG infloor heat with HWH with a heat exchanger in the HWH is too expensive to run!

I have the above home on a monolithic slab. ...LPG to run the HWH and a heat exchanger pipe running through the HWH to heat my floor...TOO DANG EXPENSIVE TO HEAT MY HOME THAT WAY! Suggestions on how to make it more efficient would be appreciated. A air to water heat pump? A heat pump water heater with a heat exchanger pipe running through the HWH? A solar system of some sort?

Asked By Ed Jones | Jan 25 15
0 Answers

Mud sill seal

In the FH article about air sealing a mud sill they used a EPDM product. The mud sill was 2x6 but it looked like they used the gasket intended for 2x4 material. I believe the product is available in both 2x6 and 2x4 widths and was wondering why the intended product was not used. If the 2x4 gasket is acceptable it would save some $.

Asked By Robert Brown | Jan 22 15
2 Answers

Insulating solid brick house

Hello! I've been reading this forum for awhile now and there's so much good information about insulating I don't know which direction to head in. I have a 1950s ranch in Michigan that is under renovation. I currently have most of the walls exposed and wanted to know the best way to go about this. It's a solid brick (like small cinderblock?) house with furring strips and 2 layers of drywall on the inside. On the outside I have furring strips with vinyl siding.

Asked By Jeff Hogarth | Jan 9 15
5 Answers

Condensation prevention for houseboat insulation

Hi, this is a revisit of the question about trying to prevent condensation and water damage while insulating, but in this case for a marine houseboat. We are talking a 3/8" steel hull, 1" air gap, with wooden frame and "rockwool" insulation bats just under 6 inches deep, then vapor barrier, wood veneered plywood sheeting interior walls. Vessel will have hydronic radiant floor heat using grooved plywood with aluminum face for the PEX tubing, and engineered wood flooring, just under 8' deck to deck height. A 15 ft beam, and a LOA of 92 ft..

Asked By John Shank | Jan 16 15
2 Answers

Cathedral attic moisture

I have an attic converted to living space where the roof is also the cathedral ceiling. Most bays go from soffit to ridge and are insulated with fiberglass and a foil barrier with a Duravent installed so that there is always an airspace from soffit to ridge. Those bays are mostly fine. The areas I'm having a ton of ice and moisture on the sheathing is where the bays are interrupted and there is only a ridge vent. Should I fill the bays solid with spray foam? Or should I at least foam up the ridge vent from the inside on those bays?

Asked By steven pereira | Jan 13 15
6 Answers

Flat roof assembly in a hot humid climate

We are going to construct a very modern home with low pitched roofs (1/4" per foot on 5 separate roof levels) being constructed of 18" trusses, utilizing Advantech sheathing for the deck, then a vapor permeable fluid or adhered membrane, then rigid Polyiso board varying from a minimum 1" thick to 6" to create the slopes, then Densdeck Duraguard and finally a fully adhered, highly reflective PVC membrane. Underneath the deck, we intend to use 6-8" of open cell spray foam.

Asked By Norman Luke | Feb 8 14
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