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26 Answers

Can I install XPS foam board over plywood sheathing, when using concrete board siding?

I was also going to fill the interior stud walls with Fiberglass bats backed with 6 mill vapor barrier. I'm located in southern ontario Canada; just outside of Toronto.

In Energy efficiency and durability | Asked By Mike Tew | Sep 9 12
2 Answers

Does anyone know anything about "Smart Foam" used for insulating walls and attics?

There is a company out of Nebraska that claims smart foam has an R value of 10 and is the best for attics and walls.

In Green products and materials | Asked By Parker Lahti | Sep 11 12
4 Answers

What are the effective options to insulate existing walls?

If this question has been answered please point the link - I am unable to find past material.

The home is over 50 years old. The wall cross section is: brick veneer, cavity, celotex type material, framing, and plaster on board inside. There is no other insulation material in the wall cavity between the celotex and the plaster.

The blown in insulation folks say they are the best option. The injection foam folks say they are the best in R value and performance - that the blown in settles over time and that it does not control air movement enough. Of course the foam is more expensive.

In Energy efficiency and durability | Asked By Matthai Markose | Sep 8 12
9 Answers

What design load factors for rafters should be used when you are building a PERSIST type roof?

The roof from the outside in, consists of standing seam, plywood, vent channel (cold roof) 2x4's, 9" ISO, ice and water, and plywood are used above a rafter?

there is wood cladding or sheetrock on the cathedral ceilings....
I have snow loads of 75-80 lbs/sf per CCREL...zone 6A.
What if PV or hot water Solar panels are added to roof?

In General questions | Asked By brad hardie | Sep 11 12
3 Answers

Domestic Hot Water Heating Options

I'm looking for some advice on the most efficient, cost effective way to heat DHW for my project currently being built. The project is in zone 6 and includes two residences, a main residence and an "in-law" apartment separated by an attached garage. Both homes will be spaced heated by the same pellet boiler located in the basement of the main residence. I'm thinking that an indirect fired hot water heater might be the most efficient atleast for the main residence but I'm not sure about the feasibility of doing this for the in-law apartment.

In Energy efficiency and durability | Asked By Brian Beaulieu | Sep 12 12
3 Answers

Adequate attic ventillation

The home I am building has a hip style roof system with a 10/12 pitch. There is a lot of unused space up there but a limited amount of ridge vent and the soffits are vented most of the perimiter. My builder is concerned about the amount of heat and its effect on the roof shingles. Should I add a roof vent and if so what type would work best. Thanks for the help. Dana

In Mechanicals | Asked By Dana St.Ours | Sep 11 12
1 Answer

Problem with calculation

So I have wrapped my feeble mind around this for the last time........

what am I doing wrong???????

I am calculating temp at the inside of my sheathing - but keep getting answers that don't seem right.....
Zone 6A 8200 HDD - average mean temp over three months is 12.13F, but I am using 2F for my calculations. Inside temp is 70F, RH % 35, Dew Point is 41F.

Here is the wall.....from the outside to the inside

In Energy efficiency and durability | Asked By brad hardie | Sep 11 12
1 Answer

Is there a supplier for Larsen Trusses in Edmonton, Alberta?

I'm wondering if this is a cheaper alternative to the double 2x4 wall system.

In Green products and materials | Asked By Mick Graham | Sep 11 12
6 Answers

Pros and cons of using 1" foam for exterior wall thermal break

I am building a garage in Northern Wi and want to use Tuff R against OSB sheathing. The insulation will be an additional 3" of foam board in the cavity wall. (2x4) Some living spaces are involved, but moisture from occupation should be minimal as the building is not plumbed. Walls will be sealed inside and an interior vapor barrier used. Caulking applied to all exterior stud joints. I want to apply a vapor barrier between the OSB and the foam for release of moisture. I am thinking of using 15 felt which is typical for stucco installations.

In Energy efficiency and durability | Asked By roger aiken | Sep 9 12
5 Answers

Dehumidify only?

In Boston area, 5A region. I own a condo in an old building with average insulation and air sealing and a gas forced-air furnace.

I currently don't have central AC. My furnace needs replacing, and AC is cheaper as a package install. My city has about 400 cooling degree days per year, and my 1000 sqft condo is on the first floor and shaded by other buildings, so the heat is not too bad. Humidity is, however. A whole-house dehumidifier with a DIY install would be cheaper than AC, and we could conceivably take it with us if we moved. It would also handle humid days in the spring and fall.

In Mechanicals | Asked By Stephen Thrasher | Sep 6 12
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