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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
8 Answers

First, thanks to everyone here for all of the advice and knowledge I've gleaned as a reader for the past year.

Asked By David Baca | Dec 31 12
13 Answers

In PA I've undertaken a renovation project on a 110-year-old home. The original structure is stone/brick and stucco and the kitchen/bath addition (constructed 50-70 years ago?) was built from lumber.

The kitchen and bath existed on a rotting wood beam foundation and severe water and termite damage was present in the foundation and walls, which buckled. I demo'ed these two structures and the underlying foundation.

Asked By Lisa Weissbord | Jan 8 13
2 Answers

Hi. This is a follow-up to my question posted here:

http://www.greenbuildingadvisor.com/community/forum/gba-pro-help/26311/s...

I'm looking for some hard evidence or resources that can guide me in the right direction. From what I have been told in prior research is that it is NOT OK to walk/rake over freshly blown cellulose insulation so that it can be raked out. The installer wants to do this, and I do not.

Can someone set the record straight for me? Thanks!

Asked By Rocky Pembroke | Jan 4 13
15 Answers

I am planning the second floor of a new build home in climate zone 4 which i am completing in stages due to money constraints. The building envelope is hot roofed with 4" cc spray foam on the roof deck and 5.5" of rock wool beneath that, the walls are 2x4 with cavity insulation and 2" of XPS on the outside of the wall sheathing. The walls are further air sealed with a combination of Knauf eco-seal and cc spray foam and the basement walls have 2" of cc spray foam so the envelope is reasonably tight. Fuel source available is propane which is already piped into the home.

Asked By jack ostrick | Jan 4 13
3 Answers

First, this is for residences in Climate zone 5. We have seen several insulation companies recommend a flash and batt system to insulate a roof system in an unfinished attic space. The recommendation is for 3" of CC foam (R-20 to R-23) covered by an R-21 unfaced fiberglass batt for a total nominal R value of ~ R-40. The fiberglass batt is visible from the unfinished attic and according to the insulation company meets the dual role of an ignition barrier and an R-21 thermal break .

Asked By Jeffrey Rhodin | Dec 27 12
4 Answers

I understand the importance of super insulating the underside of a slab with large amounts of XPS foam, especially in my very cold climate (northern Maine). I have run across a unique foundation design of a passive house in Falmouth, MA, by architect Steven Baczek (http://www.deapgroup.com/Falmouth_PH.html). It involves insulating ABOVE the slab, essentially leaving the slab out of the conditioned space. His design involves 4" of XPS rigid foam resting on top of the slab, followed by 2x8 16" OC boards spanning the slab, resting on a 2x4 strut. 3/4" T+G subfloor covers the 2x8s.

Asked By Matthew Michaud | Dec 30 12
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