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1 Answer

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
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
18 Answers

I am ready to insulate a new home, and need to make a final decision. I need help.
I have been the recipient of many helpful tips and guidance from thes pages as well as other green forums and it's all kind of coming to a head in our new home build as I attempt to make a decision about the insulation we will use. Here is the specs on my houses wall stack up

LOCATION: 47460 On the line of upper climate zone 4 and lower 5

2x6 exterior walls, 1/2 inch sheathing with tyvek, 1.5" polyiso foam with taped seams, vinyl siding

Asked By Anthony Hughes | Aug 8 14
11 Answers

Hi,
I need some advice...preferably before I cut a bunch of holes in the walls or ceiling and find out that this was a pointless venture.

So the details:

900sq foot one level, mostly open plan, highly insulated and sealed home.
Heating climate...like really... a lot. -40 C is not unheard of for stretches of time. More typical is -20 C

The house is powered completely with PV.

Heat is supplied by radiant slab, a bit of passive solar. I am also putting in a small wood stove in the next few days.

Asked By keith ahlstrom | Aug 21 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
12 Answers

All this talk about ductless minisplits is making me dizzy. If a forced air furnace gives a bad atmosphere in a building, doesn't a minisplit per room just give many bad atmospheres?

Dana reminded me on another post that a forced air furnace increases infiltration/exfiltration. Well, why doesn't a minisplit heater or cooler do the same?

Asked By flitch plate | Aug 19 14
16 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
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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