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Answers

This is probably only a hypothetical question as I doubt I could talk my wife into a composting toilet but…If we have a tight home with balanced ventilation, and if we had a composting toilet that has a small 5W fan continuously exhausting air - how would we provide make-up air?

Asked By Scott Tenney | Jul 24 14
Answers

As a long time visitor and few years member, I have tried to absorb the lessons, opinions, science and conjecture presented here. However, I now find myself confronted with conflicting theory regarding unvented roof profiles.

For my own project, (high altitude, dry, -10 to 90 F) I have regarded the "top" layer of sheathing in an unvented assembly to be essentially in dead space - not exchanging air or moisture - the underside in contact or glued to impermeable insulation, the top side sealed off from all contact with the locally required ice and water shield over the entire roof.

Asked By Roger Berry | Jul 24 14
1 Answer

The question is when going with foam installation on the attic CEILING between the rafters only not on the attic floor, which is recommended for attic CEILING open or closed cell.

Asked By TERRY KELLEY | Jul 24 14
13 Answers

I put the cart before the horse, and selected the house depicted below to build in the Adirondacks, NY. After working out the design details inside the house, I moved to the outside. I questioned the building designer about the low profile 3/12 pitch roof and how it is vented on the high edge, and the reply was "this home uses water impenetrable closed cell urethane insulation, sprayed in to fill the cavity from below prior to drywalling, and it therefore unvented.

Asked By Don Moore | Jul 23 14
8 Answers

Hello folks,

First, I'd just like to say how thankful I am for the invaluable resource that is GBA. I spend A LOT of time reading the blogs and Q&A and I find that pretty much any question I might have has been covered here already. Though sometimes my understanding gets a little vague regarding certain details so I am hoping for some input on a potential wall detail.

Asked By Noah Byler | Jul 23 14
4 Answers

We are in the planning phase of a passive house near Louisville, Ky. The site is a South facing hill with a great view of fields, trees and a creek. We plan on a walkout basement under a 2300 square foot home. I am concerned about moisture through the wall of the basement. Some precast concrete wall providers guarantee water tight walls with insulation on the inside. If they are used what precautions should be taken relative to the floors and vapor pressure to the inside?

Asked By Paul Nicholls | Jul 22 14
19 Answers

I am building a home with a conditioned attic. I will be spraying 11-12 inches of open cell foam underneath the roof sheathing. I need to allow the sheathing to breathe to the exterior, for it will not breathe to the interior with the 12 inches of foam. Thus, I was wondering if anyone was aware of a roof underlayment (other than building paper) that is breathable, durable, and that has a high exposure rate.

Asked By JAMES MOYER | Jul 22 09
4 Answers

I had a new central air installed, and the gas line is against the flue on the heater.

Asked By MARK ALATORRE | Jul 23 14
3 Answers

Hello,
I currently building an addition and plan on putting up a knotty pine tongue and groove (1x6, 3/4" thick) ceiling attached to the bottom of scissors trusses. The trusses are 24" on center. I plan on putting up 5/8" drywall first to get an airtight assembly. The tongue and groove pine is end matched (ends are tongue and groove as well). My question is this, with the drywall up, am I ok not ending each piece of pine on a truss seeing that the ends are also tongue and groove, or am I asking for trouble if the boards aren't nailed on the ends?

Asked By SCOTT KOONS | Jul 23 14
5 Answers

I am about to start framing up walls for my woodshop. The existing slab slopes from back to front a total of about 4" over the length of 28'-0"....yes, 4". The concrete crew did a terrible job. I need some advise on the best/most efficient way of dealing with this slope in the slab when framing the walls. I feel a tight connection with a PT sill plate to the slab is crucial. So, I could:
1) Frame walls square on ground and then deal with space between PT seal plate and bottom plate of wall with large shims. Doing this though, I worry about a good connection to the sill plate.

Asked By Zane Morgan | Jul 23 14
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