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15 Answers

I have been told a number of times that using more than 4" of cc spray foam (in a wall or roof assembly) has little value at increasing r-value. In other words, does using more than 4" not have a linear increase in r-value? The reason I ask is b/c I need the recommended r-35 against the bottom of my roof sheathing (with blown-in cellulose in the remainder of my cathedral truss) to prevent the roof sheathing to dip below the dew point and create condensation. Any thoughts? Thanks.

Asked By Matthew Michaud | Feb 2 13
1 Answer

I am wondering if anyone has come up with a formual that calculates the minimum stand off for a canadian rain curtain that take into account the exterior wall insualating materials, r value, max. wall ht and building location/elevation?

I am also trying to locate some information relating to any benifits to reduced energy consuption a raincurtain might add. Feedback from my clients has been all over the place on the retoros we have completed and they most likely also include upgrades to the roof & attic insulation at the same time

Thanks

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Asked By Matt BLANC | Feb 2 13
5 Answers

Could this work in cold climate 5? Bsmt floor Sealed and thermally broken from upstairs units. Would a Vented basement make that possible?

Asked By matt berges | Jan 30 13
1 Answer

I have two bay windows to build and I want to keep the insulation levels consistent. I using 1 1/2 exterior rigid foam with lap siding on the exterior and 2x6 framing

Asked By Dan Easton | Jan 30 13
2 Answers

I'm a remodeler in southeastern CT. I will be building my own house within the next year, and I'm looking for a resource to learn how to install dense pack cellulose.

Asked By Samuel Kilpatrick | Jan 25 13
Answers

Hello.
I was wondering if anyone has a solution for this problem.

I recently installed a power-vented natural gas water heater to replace a 20-year-old electric.

The installation was done by me and inspected by both a gas fitter and the local gas company. All is good...

However, there is a significant amount of cold outside air coming in the 2" (system 636) exhaust from the power vent, and its enough to spin the fan on the power vent backwards. (when not running of course)

Asked By R Hunt | Jan 24 13
17 Answers

I'm advising the onwer of a 50 unit, 6 story multifamily building on how best to cost effectively control excessive heat gain in the summer. We started by looking into louvered overhang retrofits made from aluminum and attached to the 6th floor, south side units. ( The 1-5 floors have the balconies above them to shade some.) The price? $30,000 for 5 apartments. Not in anyone's price range. The existing glass is a tinted charcoal gray Insulated Glass Unit. For that reason, window film installers are saying that they can't guarantee the glass won't break if they install.

Asked By mark faultersack | Jan 21 13
10 Answers

In researching high efficiency buildings, and deep energy retrofits, I am confused why in a tight building, it is still suggested to insulate the roof/ceiling more than the walls.

Asked By Matt Friesen | Jan 22 13
6 Answers

I'm having a log home built wth cathedral ceilings. I plan to have 1 1/2 to 2 inch closed cell polyurethane sprayed onto the interior side of the roof sheathing with blown in insulation filling the balance of the twelve inch rafter (I beam style of rafter) cavity. This wll be an unventilated roof. Tongue and groove will be used on the ceiling surface. I understand the spray foam will act as an air barrier, and the tongue and groove is very air permeable.

Asked By Rick Schneider | Nov 7 12
4 Answers

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 .

Asked By Michael Chelnov | Nov 11 12
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