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15 Answers

Slab on grade flooring options

I have a cottage that is being replaced by a retirement home .It is on bedrock in eastern Ontario and I plan to build slab on grade unless there is a better option .It will be a 1200 sq. foot 1.5 story.I am hoping to build with advanced framing style and sheath it with 4 inches of exterior foam. My question is about the concrete floor.I realize I can polish it and etch it but I am not sure about comfort of the hard surface and the temperature of cold concrete on your feet .I wonder if I could put foam board on it ,then an underlay plywood to lead to a normal house floor covering ?

In General questions | Asked By bob holodinsky | Jun 10 13
7 Answers

Balancing an HRV

Our HRV is installed, the ducting sealed, and the wall/ceiling diffusers are in place. I still need to balance the system so i armed myself with a couple of flow grids and a magnehelic gauge.

The balancing equipment seems somewhat straightforward (i hope) but my question is about the diffusers: where do i begin the balancing procedure? with the diffusers off? on but fully open? on but half open?

here are 6 diffusers: 2 in the crawlspace, exhausts in the kitchen and bathroom, and supplies in the bedroom and living room...thanks again

In General questions | Asked By erik olofsson | Jun 10 13
3 Answers

Missing tar paper on brick exterior/wood stud house?

I own a 1922 brick bungalow in Illinois. The main floor has one wythe of brick on the exterior, then an 1 1/2" air gap, then wood stud walls. I want to drywall the ceiling and walls in one room -- the previous homeowners removed the original plaster and lath and added fiberglass insulation and drywall, which I removed. There is tar paper attached to the studs only on the bottom third of the wall (photo attached).

In General questions | Asked By HT Miller | Jun 10 13
4 Answers

Wood basement as tornado shelter?

With all the recent severe weather in the mid west, lots of attention has been directed toward building in some form of shelter. I;m leaning toward a PWF (Permanent Wood Foundation) for both cost and thermal performance reasons. Would a PWF basement provide a suitable "safe room" or would it be advisable to build a shelter, within the basement, out of CMU or even poured concrete?

In General questions | Asked By Jerry Liebler | Jun 8 13
31 Answers

Advice for rebuilding in central Oklahoma?

Two degrees of separation from two of the many who lost homes in the recent tornadoes near Oklahoma City.

I wanted to tap the collective intelligence to work through how to build back better (or retrofit surviving homes for resilience), both in terms of ‘what’ and ‘how’ — especially, to discuss what is locally appropriate and cost-effective, specific technical resources, etc., given the unique and extreme conditions in Oklahoma (tornado, fire, hail, and recently earthquakes...!).

In Energy efficiency and durability | Asked By David Gregory | May 24 13
14 Answers

Blower door and HRV question

i just had a blower door test done on our new R-2000 build. The house is almost ready for occupancy. The initial test showed about 1.3 ach @ 50 pa but I was sure it would test far tighter.

After snooping around, I realized that both the interior supply and exhaust diffusers for the HRV were badly hemmorrhaging air. After sealing both the exterior supply and exhaust vents, the ACH dropped to .8 ach. Why is this happening?

In General questions | Asked By erik olofsson | Jun 2 13
1 Answer

I have a home with two stained walls

I have a home with two stained walls. One wall is on a corner to the house. The other is in a angle (upper) near the roof.
I'm sending some pictures so you can see the stain.
I have cleaned it up and it comes back again.

In GBA Pro help | Asked By blanca goertzen | Jun 10 13
3 Answers

Opinions or experience with APEX block?

Searching for wall assembly options, weighing cost, thermal performance, durability and so forth, below and above grade, SIPs, ICF, SCIPs, brought me to APEX block. Cementious mix with EPS type of ICF, the EPS form creates a tubular-type grid of concrete with rebar. Supposedly uses something like 25% less concrete than standard ICF, while claiming R-38, and uses recycled EPS at a lower cost than ICF. Anyone have any opinions/experience with the product?

In Energy efficiency and durability | Asked By Sal Lombardo | Jun 5 13
1 Answer

Propane 'energy pods'

I'm regularly seeing banner ads in my GBA feed for propane 'energy pods', linking to this site: http://buildwithpropane.com. I'd welcome comments from those better-informed than I on the claims made there which rather fly in the face of all I thought I understood about the cost effectiveness and carbon emissions of this energy source.

In Mechanicals | Asked By James Morgan | Jun 9 13
8 Answers

Fun With Fluids

(starting 1:30 minutes into this video)
Thorsten Chlupp mentions a fascinating concept ...Stratification

It seems we can "store" a not-so-dense fluid above a dense fluid....

It's kind of Intuitive that a dense fluid will support a not-so-dense fluid.

What's Not so Intuitive is that the "fluids" might be in very distinct layers.
...separated by "Internal Waves"....

similar to this demonstration

In Energy efficiency and durability | Asked By John Brooks | Jun 8 13
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