Q&A: A Forum for Green Building Experts and Beginners

[Click map to enlarge]

Please register for a free account or sign in to ask and answer green building questions. The usual rules of courtesy apply: 1. Be nice. 2. If you can't be nice, be polite. 3. If you can't be nice or polite — well, please be brief. To attach a photo or illustration: Under the box labeled "More explanation," look for the words "File attachments." Click that, and you should be able to attach a photo. Thanks for joining the conversation!

2 Answers

This page describes how to build a DIY blower door:

http://www.builditsolar.com/Projects/Conservation/BlowerDoor/BlowerDoor.htm

Basically you use a furnace blower and a cheap magnetic or tube-of-water manometer. You can't finely tune the speed of the blower like a professional blower door, but given the few built-in speeds of the motor, you can generally find a speed that yields close enough to 50Pa that you can extrapolate the CFM50.

In Green building techniques | Asked By Nick Welch | Aug 21 14
3 Answers

I got some basic ideas from Martin's fine article here: http://www.finehomebuilding.com/design/departments/energy-smart-details/...

In General questions | Asked By Tommy Detamore | Aug 21 14
5 Answers

Not including the cost of the blower door test itself, I am looking for a ROM materials and labor cost per ft-2 to seal up a conventional 2 x 4 framed house, sheathed, sided, windows, doors, stud bays, lid, etc.....?

If someone that has done it can estimate labor hours to get to 5-7 ACH-@ 50 I can factor my local labor rate. Please include the trail and errors, IR and smoke back and forth, etc. Or if you sealed up some ft-2 home let me know how long it took...

Thanks!

In PassivHaus | Asked By Terry Lee | Aug 20 14
1 Answer

Thank you for your time to answer my question!

I have 700 square feet to insulate -- is an attachment room to a frame house, built very poorly, and is very cold and hot. I'm doing now fixing up.

Question: I have walls 3 inches deep, and celling is 12 inches deep. I was going to spray foam with closed cell.

Can I maybe (to reduce cost) install fiber insulation? Or styrofoam, 1-2 inches, then spray with closed-cell over that?

Or is it a good idea to spray one inch of closed-cell and do the rest with open-cell over closed-cell?

In Energy efficiency and durability | Asked By Enes Enes | Aug 22 14
Answers

The Passive House Alliance Vermont chapter would like to invite you to attend the 2nd Annual 2014 Passive House Symposium. The one day event will be held at Vermont Technical College in Randolph VT, on Thursday, October 2nd.
We now have a Pay Online Link !! For Attendees @ 50$ for the day Lunch included and 25$ for PHAUS and BPPA-VT members. Below
- Key Note Guest Speaker – VT Lieutenant Governor Phil Scott.
--Report update on MLS listings, Appraisals and Financing for High Performance/ Passive House buildings by Jeff Gephart from Efficiency Vermont.

In PassivHaus | Asked By Chris Miksic | Aug 21 14
7 Answers

I'm helping a homeowner improve his 1974 ranch, zone 5 Ohio. Attic currently has 6" of cellulose, no air sealing. Blower door results were predictably awful. After removing all recessed light fixtures and fully air sealing the attic floor, I'll be adding more cellulose. There are no mechanicals in the attic, except for a plumbing vent and a little wiring.

Question: are there any potential problems in simply blowing in more cellulose? Even up to touching the roof sheathing near the eaves? (It wouldn't take much, in fact, to completely fill the attic, if one was inclined..)

In Energy efficiency and durability | Asked By Andy Chappell-Dick | Aug 20 14
12 Answers

Hi

I'm new here, and I really appreciate all the great information that has been provided by GBA and its users.

I've been reading a lot about cathedral ceiling insulation, and it seems like it is a fine line between success and disaster when it comes to moisture control. So now I have a few questions myself that I hope someone could help me answer.

In Energy efficiency and durability | Asked By Chris Jensen | Aug 18 14
7 Answers

Hi all,

I would like folks to offer any advice/criticism on the following wall and roof assemblies from a moisture control standpoint as well as any other concerns they might have. In addition I have a few specific questions on HVAC options. I know that many of my concerns have been addressed in various Q&A's but it is the specific circumstances that I am concerned about here.

In Energy efficiency and durability | Asked By Lowell Garner | Aug 20 14
6 Answers

I hate to continue asking what seems to be a different wording of the same question but bare with me. My house is 2x6 exterior walls, 1.5 inch of polyiso rigid fiberglass faced foam outside the sheathing and Tyvek. We are in the 47460 zip.

I would like to know the best way to achieve the tightest wall possible but still allow my sheathing to dry accordingly. 1-2 inches of closed cell in the stud void is something Dana said would be OK, so I am leaning towards that but want to be 100% sure it's OK.

In Energy efficiency and durability | Asked By Anthony Hughes | Aug 20 14
8 Answers

We are doing rigid foam on 4500 sq. ft. of exterior walls at 4" thick and 4500 sq. ft. of roof at 8" thick in a REMOTE application.

We are attempting to find the best value for our exterior foam insulation.

So far the best value ($26 for 2"x4'x8') we could find was NeoPro TK. Seems to be a new product so not a lot of info on this "revolutionary" new material. http://www.permarproducts.com/insulsheathing.html

Our previous first choice was Foamular 250 http://www.foamular.com/foam/products/foamular-250.aspx, until we started getting quotes ($34 for 2"x4'8').

In Green products and materials | Asked By Eric Burhop | Aug 20 14
Register for a free account and join the conversation


Get a free account and join the conversation!
Become a GBA PRO!