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2 Answers

Tear-down with an existing uninsulated basement: convert to slab on grade?

This question might have an obvious answer, but I haven't been able to dig up anything on google. If I were to purchase a tear-down property that had an existing uninsulated, fieldstone basement, what would be the best course of action to build a high performance house? Fill it in with dirt then to then create a slab on grade? Tear out the fieldstone and use the existing cavity to create an insulated basement (while also hopefully re-using the fieldstone on site for something useful like a wall)?

In Green building techniques | Asked By Ethan Fahy | Jul 21 14
19 Answers

How to keep cool in and heat out?

I am not in construction or an architect, just someone who would like to live in/build a small, comfortable, energy efficient home. I don’t need and could never afford a Passive House. Don’t even know if one would work where I live. I live in the low desert southwest near Phoenix. Living is very different here than in cold weather areas. And very different than Florida or humid areas of Texas. Outside temps over 100F in shade 5-6 months; highs 115F; nighttime lows 95F for at least 2-3 months. Low humidity 10 months. Little or no drought resistant shade trees.

In Green building techniques | Asked By Anneal G | Jun 27 14
4 Answers

Composting toilet in a Passive House?

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?

In PassivHaus | Asked By Scott Tenney | Jul 24 14
3 Answers

Unvented roof assemblies and roof deck vapor permeance

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.

In General questions | Asked By Roger Berry | Jul 24 14
5 Answers

Precast concrete basement walls

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?

In General questions | Asked By Paul Nicholls | Jul 22 14
1 Answer

Ventilation to cool down poorly-insulated house

My wife and I recently bought an old (1880's) two-story duplex with separate apartments on each floor, each about 750 square feet and very poorly insulated. We have long-term renovation plans, but our primary near-term complaint is the inability of the apartments (especially upstairs) to cool down at night -- even with our quite cool summer nights here in Northern Colorado and all the windows open. We don't want air conditioning, but we would like to improve night-time ventilation.

In Mechanicals | Asked By Kevin Ummel | Jul 24 14
2 Answers

Spraying foam on the ceiling between the rafters.

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.

In Energy efficiency and durability | Asked By TERRY KELLEY | Jul 24 14
14 Answers

Roof insulation/venting in heavy snow load climates

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.

In General questions | Asked By Don Moore | Jul 23 14
4 Answers

Can you run the gas line against the flue pipe on a heater?

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

In Building Code Questions | Asked By MARK ALATORRE | Jul 23 14
3 Answers

Tongue-and-groove ceiling

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?

In Interior design | Asked By SCOTT KOONS | Jul 23 14
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