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

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2 Answers

Hello, I would like advice on insulating my garage. It has cinderblock walls and an unvented hip roof with no ridge or soffit. Rafters and sheathing are exposed and the outside is metal panels. I can't really alter the outside appearance of the home due to my local historic society (home built in 1842). My question is, can I glue/screw rigid foam board directly to the underside of the roof sheathing, in between rafter bays, then finish by screwing plywood or drywall directly to the foam board. Is there risk of moisture build up (between foam board and sheathing) if I do this?

Asked By Dan McGonigle | Aug 22 14
19 Answers

So, My AC system died last spring, and I was prepping to put new windows (impact resistant, low e) in my house... My house is approx 2200 sq.ft in Florida, south of Tampa... Zone 2A

I had a 4 ton system, and knew that would be too big as a replacement, but my HVAC tech replaced it with what was here and said he could tune it... Now my house averages 55%rh or higher... Up into mid 66-67...

Asked By Chris Marriner | Aug 18 14
2 Answers

Question about sealing up a crawlspace with foam.

Our house at some point had an addition on the front put on. It is more like a bump out that is 6' x 16'. They did dig for a foundation and built a cinder block wall to hold this up. There is a dirt floor in the crawlspace that is above the level of the dirt outside the block wall. This crawl space is only 18" deep stays dry and only accessible through an old basement window well window that they built this in front of. Needless to say I never went in there.

Asked By William Heiden | Aug 22 14
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.

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/...

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!

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?

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.

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..)

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.

Asked By Chris Jensen | Aug 18 14
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