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1 Answer

Insulation Effectiveness

Our basement wall system is made of 9' high insulated precast concrete. Superior Walls manufactured and installed the system. It is their "Xi" wall with 2 1/2" of closed cell polystyrene insulation (Dow Styrofoam) = R12.5. Our builder installed (stuffed) faced 3 1/2" fiberglass batts (R11) in the remaining 6" deep cavities between the wall's metal studs.

In Energy efficiency and durability | Asked By Gary Geminn | Jan 17 13
2 Answers

Applying Thermal Barrier to Rigid Foam at Rim Joist

I am a homeowner planning to air seal the house. Starting with the basement because it will be easiest.

At the rim joist I am going to use rigid foam because it is cheapest and will be a good starter proejct.

I understand some locales do not require a thermal barrier to cover the foam, but I would like to add one for safety.

Here is a list of thermal barriers: http://www.foam-tech.com/theory/firebarriers.htm

A spray on sounded interesting, but none of those listed appear to be in current use, and they appear to be asbestos based.

In Energy efficiency and durability | Asked By Erich Riesenberg | Jan 16 13
2 Answers

Type or Parging & waterproofing for old concrete foundation

Good day,

In General questions | Asked By Michael Genin | Jan 17 13
3 Answers

How do I calculate volume and then confirm coverage of dense-packed cellulose?

I have odd sized rafter, wall stud and floor joist bays and Larsen trusses to boot with no top plates. This poses a problem in calculating the quantity of cellulose I need to get the optimum R-value (assuming the best is 3.5 to 4.0 lbs/ft3) in my all season cottage.

Can anyone point me to a formula on-line that I can punch in my numbers and get the volume estimates for my different dimensions of cavities at different densities (R values)?

In General questions | Asked By Oak Orchard | Jan 14 13
4 Answers

Suggestions for retrofit rainscreen window flashing?

Because of moisture entrapment, I need to rebuild the outer portion of a wall. Originally a stucco on durock on WRB, on plywood sheathing, It is being replaced with Hardie plank on furring on Roxul rigid IS on WRB on plywood. This means the windows will end up being inset...and flashing will have to be installed at the sill, jamb and head. I'm concerned about the sill specially... how to handle the ends of it where it butts up to the jamb. I would appreciate creative ideas about how to handle this intersection specially...Also I'm open to any ideas for the head and jamb .

In GBA Pro help | Asked By Michael Chelnov | Nov 11 12
34 Answers

Window glazings interior temperatures in cold outside and condensation

I am unsure that my windows perform as they should,
this is our second winter in the new house, and the first one we had to get rid of ridiculous humidity level caused by the building time.

Now humidity as set to 35-40% for now,
and i still see condensation at bottom of all windows on the first real cold night.
Yesterday was a ~ -15c and i've measured down to 0c at the bottom of the glazings.

What is supposed to be normal temps for inside pane of high eff. windows ?
Is there any test results or tables somewhere i could check ?

In General questions | Asked By Jin Kazama | Nov 30 12
2 Answers

Can I put exterior sheathing over 1 1/2" rigid insulation on an exterior wall w/o hurting the structural integrity of the house?

I want to put 1 1/2" rigid insulation on the exterior walls of a new home I will be building soon to help with the thermal transfer. I have used it before but have always put the rigid over the sheathing then strapping over the rigid. I would like to eliminate the strapping and put the rigid on the studs then the aspenite over the rigid. I would screw the aspenite to the studs but am concerned that the walls might loose some ridigity and strength. I am using vinyl siding so my other option is to use a longer siding nail and put the rigid over the aspenite.

In Green building techniques | Asked By Mark Audette | Jan 16 13
3 Answers

Is a 16 SEER air conditioning system worth it over a 14 SEER in Houston, TX?

Building a new house, 1.5 story and looking to get the most bang for my buck. Doing 2x6 walls with polyseal spray and cellulose insulation. Will a 16 Seer be worth the addition $3-4 k I have been quoted? Energy prices here are currently 10-12 cents per kw hour, but do rise occasionally. I am most concerned about home comfort though and have been told by some folks that higher seer units in this humidity are not worth it. Any thoughts?

The house is appx 3500 sq ft with 2700 down and 800 up. I am looking at two units, a 4 Tom down and a 2 ton up.

In Mechanicals | Asked By Dustin Gohmert | Jan 16 13
4 Answers

Exterior insulation while re-siding with an interior poly VB

I've been reading a lot of articles and questions/answers from this site and many others in preparation for a re-siding project. I am located in South-East New Brunswick, Canada, our climate zones run different than the US, but I believe it would be similar to Bangor ME which is zone 6A.

To the best of my knowledge the wall construction (1977 build) is, from the outside in, vinyl siding, felt paper wrap, board sheathing, 2x4 walls, fiberglass batt insulation, 6mil poly VB, 1/2" drywall.

In General questions | Asked By Scott Smith | Jan 9 13
7 Answers

Adding rigid foam to living space side of wall


I have a project in the Boston area where I would like to add and inch or so of rigid insulation to add some R value and knock down the thermal transfer and air-seal. The problem I'm saddled with is the wall that I need to work on is the gable end of the house and I'd have to extend the roof and move the electric meters and weather head if I thicken up the exterior wall by adding the foam and rain screen, and also add the new siding.

In Energy efficiency and durability | Asked By Steve Greenberg | Jan 15 13
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