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1 Answer

We are to build a Passive House in PA, and have "borrowed" a technique from another PH in Virginia, where part of a typical EPS under slab was substituted with a layer of perlite bags placed over just 4'' of EPS. I believe it also allowed us to reduce the slab thickness to 4'' (in the center).

Asked By Lucyna de Barbaro | Aug 22 14
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
15 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

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
14 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
19 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
17 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
4 Answers

I have been thinking about the benefit of putting XPS/EPS foam under the basement slab, and it has gotten me thinking.

I am building in zone 6, where it is quite hot for a couple of months in the summer, getting up into the 90s, and cold in the winter, getting down to the 10's (Fahrenheit) on and off for a couple of months.

Asked By Stephen Youngquist | 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
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