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7 Answers

Slab against rim joist detail please

New construction: back patio will be a slab poured against the rim joist so it is nearly level with the door threshold. Rim joist will be 11 7/8" atop a retaining wall back-filled with gravel, so there will be good drainage. The patio will be covered with a roof, and slope away from the door of course.

What's the best way to permanently protect the rim against water, moisture, and termites?


Asked By David McNeely | Oct 8 15
19 Answers

How is thermal bridging prevented?

The construction process of our home, in southeast Iowa, was completed in January 2014. The house has fiber cement lap board siding and an interior spray foam insulation. In March of 20014 we noticed moisture accumulating, in a vertical line pattern, on the east elevation of the house.

Asked By S. Schneider | Oct 5 15
7 Answers

Limited soffit venting clearance for baffles + insulation

Just installed a new roof with Maximum Ventilation exhausts and removed old fiberglass batts. I was originally planning to do the standard R50 fiberglass blow-in and soffit baffles. However, I discovered that in this 1960's back-split, the roof is quite shallow and rests directly on the double brick wall so there is only 3-4" clearance for soffit venting, leaving only 1-2" left for insulation under the baffles around the perimeter. This seems like a recipe for cold spots.

Some options:
1. Just proceed as planned; hopefully cold spots won't cause condensation on the ceiling.

Asked By Deb N | Oct 8 15
11 Answers

NON-Flanged (Insert) Window Replacement + Flashing

I changed out my rotten wood framed windows for all vinyl ones. The original wall was aluminum siding. I fixed the rotten sheathing, applied house wrap. Then strapped (furred) the wall with plywood. The pictures show how I flashed the rough window openings. I did NOT want flanged windows because I did not want to have to disturb the siding when the window needs to be replaced in the future (far into the futuer I hope). I see a lot of articles on how to flash flanged windows, but I never see methods for Insert (non-flanged) ones.

Asked By Alexander Sanita | Sep 28 15
4 Answers

Insulation type, etc.

hi all,

i have a semi-detached brick 2-family home in brooklyn. 20' x 65'. tenants are on the top floor and we occupy the first 2 floors. our ground floor is about 3 feet in ground on 3 sides and at grade in the rear. we are renovating and intend to put 2 full bathrooms and 3 bedrooms there, in addition to the laundry and utility room. we recently install a navian ncb240 which currently serves our dhw and baseboard radiators for both floors (tenants have separate boiler).

Asked By Josh Millis | Oct 1 15
2 Answers

Venting an existing flat roof

We have a row house in Chicago. The drawing indicate (it seems it was built as drawn) that we have a 1/4" per foot modified bitumen roof. We don't have soffits or ridges (just parapets on three sides and a gutter along the back). The roof structure is min 16" wood roof trusses at the low gutter end and they get bigger at the front. We have R49 Green Fiber blown in cellulose insulation in the trusses. There is no vapor barrier (as the insulation suggested) and there is two layers of 5/8" drywall at the ceiling. We have mushroom vents at 1 sq. ft. of net free area for every 300 sq. ft.

Asked By Trisha Megan | Oct 8 15
6 Answers

Vapor barrier in attic?


Asked By Lucy | Oct 4 15
1 Answer

EPA-approved wood stove with sealed-combustion design?

I'm working on a retrofit that mandates that any wood stove must be EPA approved as well as have dedicated combustion air. I have had trouble sourcing a wood stove with a dedicated combustion air inlet . Is anyone aware of a product with this feature?

Asked By John Kidda | Oct 8 15
14 Answers

HVAC selection help

My new house is under construction and I need to finalize my HVAC system soon. Some details:

Zone 4, 3800 sq feet (About 1900 first floor, 1550 second floor, 350 room over the garage), crawl space (conditioned), open web floor trusses for second floor.

I had the manual J load calc reviewed by an engineer and have sent it back for some corrections (there is better insulation than is shown and better air sealing, and a couple other things which will lower the load. He didn't add the ventilation load though, which will raise it), but as it stands right now:

Asked By Michael Geoghegan | Oct 7 15
4 Answers

Struggling with how to use foam on walkout over Canadian shield zone 7

I'm building a walkout basement (1000 sq ft) in zone 7 (NW Ontario Canada) and have purchased 1000 sq ft EPS at 5 inches and 1000 sq ft at 1 1/2" XPS (I was told its much better to use above the XPS since its much more rigid when walking on during the pour)..
I am struggling on how to best use the foam on the walkout side (I got a great deal so I have lots of EPS and XPS)..

Asked By tim brown | Aug 18 15
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