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0 Answers

Green / Passive House Architects

Anyone know of a good source for good energy efficient / Passivehouse architects?

Asked By Peter L | Nov 29 15
20 Answers

Two backdrafting appliances and dust — Do I need an HRV?

Hello, I have a problem with my house.

1) My house is probably air-tight

2) My water heater backdrafts whenever the bathroom fan is on. It's probably backdrafted every single morning (windows fog up & I feel the warm air at the flue when it kicks on....it only stops once turning off the bathroom fan).

3) Opening specific windows in the basement relieve the backdrafting of the water heater.

4) There was a lot of dust on a return-air duct that was right above the water heater. Another supply duct near the water heater had rust.

Asked By J Pritzen | Nov 26 15
1 Answer

Masonry Block Wall - To seal or NOT to seal??

In preparation to insulating my renovation of a 1970s building's masonry block wall with 2" XPS foam board attached directly to the masonry block, should I paint the interior masonry block wall with a sealer like DRYLOK® Masonry Waterproofer or KILZ 2® LATEX Low VOC?

Right now there is a thin coat of cheap latex paint on the block wall.

Russ :-)

Asked By Russell Torlage | Nov 29 15
6 Answers

SIP walls insulating the floor joists

I'm attaching a picture posted by Insulspan, the SIP manufacturer we're getting a quote from. It shows the SIP wall on the edge of the basement wall with the floor joists on the inside edge, providing continuous insulation of the rim joist. Has anyone seen this done? I thought at least 4 inches of the floor joist had to rest on the basement wall to be structurally sound. I plan on using superior walls which are 10.25 in thick and 8.25 in SIPs.

Asked By Brian W | Nov 28 15
3 Answers

Pros and cons of Grace Ice and Water compared to Tyvek Drainwrap

If applying a WRB under rigid foam insulation, what are the pros and cons of using Grace Ice and Water Shield compared to Tyvek Drainwrap, in terms of protecting the sheathing, serving as an air barrier, difficulty of installation, flashing details, and any other reason you might prefer one product over the other to serve as a WRB? Assuming that the Grace product is more expensive, do you believe that it is worth the additional cost on a 2,000 square foot home in Zone 5?

As always, any advice or opinions are greatly appreciated.

Asked By James Timmerberg | Nov 29 15
1 Answer

Visual dictionary for building terms/glossary?

I know there's a Glossary link in the upper right corner of the GBA website, but is there the equivalent of a visual dictionary for common building components? Ok, I know there are some out there (e.g., visual.merriam-webster.com/house/structure-house/frame.php), but is there a good one online that people have used, and is it possible to include a link to it from GBA? I don't always know the names of the building components (e.g., which part of a window is the stool?), and from other poster's questions I can tell that not everyone knows a rafter from a joist.


Asked By andrew c | Nov 29 15
6 Answers

Insulating a non vented vaulted ceiling in Canada


I've recently had a 10x14 foot backyard studio built for me by a local company. I asked them not to insulate it because I was hoping to save some money by doing it myself. However, after some research I'm not really sure how to continue.

The studio has a vaulted 2x6 ceiling (with one skylight) with no ventilation. The soffits also have no vents. Initially, I was planning to just shove some fibreglass batts up there, putt up a vapor barrier and then finish it off with some wood paneling. However, after researching it sounds like that's a recipe for moisture and mold.

Asked By Kirsten Quist | Nov 28 15
6 Answers

Advice for HRV/ERV on a budget

I am in climate zone 4C and building a fairly efficient home on a really tight budget. I used flashing tape and sealed all seams in my sheathing and will hopefully have a really tight home. The house is two stories, each story just over a 1000 sq ft (2100 sq ft total), and the home is designed so the majority of the living space is upstairs. I was planning on installing a single Panasonic Spot HRV in a central place upstairs, but a mechanical contractor (who was trying to sell me something) has told me that this will not be sufficient. and has recommended a Lifebreath RNC 95.

Asked By Kail Zuschlag | Nov 12 15
0 Answers

Unvented attic and wall ?

Zone3,12/12 pitch,galvalume color roof
Talked to insulation contractor and discussed options.
2x6 walls= Hardie lap siding,3/8rainscreen,tyvek,osb,air sealing,bib insulation(r23)5/8sheetrock
2x8 cathedrial roof,unvented with total elect units and ducting in knee wall area and spare room in the center=standing seam,membrane?,7/16osb,2in polyiso,membrane or taped joints?,7/16osb,7 in open cell or bib insulation.
No venting
Are we getting closer ?

Asked By Quinton Bryant | Nov 29 15
2 Answers

Best practices for HRV on a budget

I am building a simple but efficient home in climate zone C4. It will be a 3 bedroom, 2000 sq ft home. with us living mostly in the upper half. I was originally planning on putting one or two panasonic spot ERVs in but am know thinking it might be better for overall air quality, efficiency, and spreading the heat from my two headed mini-split, to put a fully ducted HRV unit in. I have been looking at the Fantec FLEX100H, and the Lifebreath RNC 95. Money is a huge issue but the price difference between two panasonics and one of these units is not much.

Asked By Kail Zuschlag | Nov 29 15
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