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9 Answers

Question on finishing brick-walled basement without exterior waterproofing

Some background info on the house:

It's a semi detached, about 100 years old, multi-wythe brick foundation, and it's in Toronto.
The basement windows are above grade.
The basement has a poured concrete floor.
The ground at the front (West) of the house never gets wet due to the front porch. Along the south there is an asphalt driveway which slopes decently - there are a couple of spots where the water ponds a few feet away and downslope from the walls. The remaining wall I can't see because it's covered by the back deck. Gutters and downsputs are good and drain away from the house.

In General questions | Asked By Jon Haque | Jul 15 15
3 Answers

Feedback on 2x8 exterior walls with 2x4 studs to limit thermal bridging

I live in Eastern Washington, Zone 5 A. 100 degrees in the summer to zero in winter with 1-3 ft of snow. I will hopefully be building a home this summer, 2016. I originally looked at SIPs but am convinced that if they are not installed perfectly I may end up with moisture problems later on. My brother suggested 2 X 8 top and bottom plates with 2 X 4 studs, (1/2 inch gap between them to break the thermal bridging), and blown cellulose insulation. Then two separate pieces of 1 inch ridgid foam insulation on the outside.

In GBA Pro help | Asked By Thomas Flanagan | Jul 28 15
11 Answers

We were looking to replace our front door which has 2 flanking sidelights

The door appears original to the house which was built in late 1890s (all glass is single-pane and the door has no weatherstripping). Needless to say, it's very drafty (we use rope caulk to seal gaps and plastic to cover windows in winter).

We've had 3 estimates for the work, all ranging between $3,000-$5,000 bucks. All contractors cite unknown condition of framing, subfloor, etc.

In Energy efficiency and durability | Asked By Christian Rodriguez | Jul 27 15
13 Answers

Insulating a wall that is exterior on 2nd floor, interior on 1st.

I hope the topic of this question is understandable. Imagine a floor plan that is a simple 2-story box (ie, 40x40) that has a single-story wing to one side. The common wall between the main structure and the wing will be both an interior (1st floor) and exterior wall (2nd).

In General questions | Asked By Clay Whitenack | Jul 28 15
4 Answers

Pretty Good House in Iowa

I am planning on building a "pretty good house" in the MidWest (Des Moines). After throwing around ideas on different wall structures (double stud, 2x6 with wet blown cellulose and rigid foam exterior), I'm curious what the prevailing thoughts are on building a 2x4 wall (16" o.c.) with 1/2" exterior plywood sheathing. 2" rigid EPS would go exterior, with WRB being Tyvek, then furring strips and hardi-plank siding.

In Green building techniques | Asked By Thomas R | Jul 27 15
8 Answers

Insulation for 1:12 standing seam metal roof

Hello all,
Newbie to GBA but we are interested in building an efficient home. We live on the edge of zones 4 and 5 in Illinois. 100% of the exterior will be EIFS. The plan is for our exterior walls to be 2x6 with cellulose in the cavity and rigid foam over the sheathing.

My question is about how to ventilate our standing seam metal roof (1:12 pitch). Our architect didn't seem to have a good grasp on green building techniques.

My questions to architect:

In General questions | Asked By Kevin Hoene | Jul 22 15
0 Answers

How much energy does the evaporator coil waste?

While working through Manual D calculations I was surprised at how much of the total static pressure from a blower motor is dropped through the air conditioning evaporator coil. In my case I had a drop of .3 iwc at the coil for a total external static pressure of .7 iwc at 990 cfm. That's almost half of the blower load being used to push air through a coil that in my climate (zone 5) is just in the way most of the year.

In Mechanicals | Asked By Jonathan Dalton | Jul 28 15
3 Answers

Insulate ducts in conditioned basement?

I have been air sealing my ducts as best I can with mastic. I now have the first 4 feet or so of supply duct from the furnace sweating pretty good whenever it's on. This is all in the basement, which we use as another family room like area, don't use it as much as the first and second floor, but a fair amount.

In the summer it's freezing with the air conditioning on and the ducts sweat for a few feet, as mentioned.

In the winter, however, it's still a little chilly, certainly not overly warm.

In Energy efficiency and durability | Asked By Jeremy M | Jul 27 15
6 Answers

Is a ductless minisplit appropriate for a house with primary wood heat?

I am contemplating installing a ductless mini-split heater in our new build house in Southeast Alaska. The climate is of course very wet, with fairly cool summers and fairly mild winters with the occasional cold snap.
We heat primarily with wood. Is a mini-split heater an appropriate choice when the wood stove is expected to do 80% of the work of heating? We want an auxiliary heater that will simply limit how cold the house will get while we are away for a long day or a weekend (to 50 degrees or so), but will not run at all when the wood stove is going.

In Mechanicals | Asked By Justin Smith | Jul 23 15
32 Answers

More confused....open vs. closed spray foam for my climate zone


I want to finish off my third floor. My house is in Richmond, VA - Climate Zone 4 - (right in the middle of the zone). House was built in 1993. The attic is walk up and rafter built with 2x8s. Here are some pics of the space:

In Energy efficiency and durability | Asked By Joe Watson | Jul 21 15
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