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1 Answer

Insulation of an interior foundation wall

The home I'm living in had an extension built with a full foundation, which also provides a heated room in the basement. I've noticed that no insulation was boot on the old foundation wall.
Should it be insulated or is it not needed?

Both rooms around that cement (foundation) wall are heated, but only one has AC (too complicated to pass a forced air duct to the new room).

In Green building techniques | Asked By Stephane Tremblay | Sep 19 15
1 Answer

Best plan for knee walls and cathedral ceiling on an ICF house

I am going to be starting construction soon on our home in Virginia (4A). It will be built with 8" ICF walls for the basement and 6" ICF walls for the remainder of the house. The ICF blocks have 5" total of foam insulation. Since the house will be very well insulated, I want to make sure my gable and knee walls plus cathedral ceiling are insulated nearly as good. The center of the home has a 12:12 pitch roof and cathedral ceiling cutting the home into 3 sections. The roof slope drops on either side to a lower pitch. Its a similar shape to a barn with a gull wing roof.

In General questions | Asked By David Clapper | Sep 19 15
10 Answers

Attic catwalk with minimal thermal bridging

I'm planning to add 12" of Rockwool batts over 2x4 ceiling joists (there's already cellulose between the joists), and looking for some creative ideas for building a catwalk with minimal thermal bridging. The usual design involves a lot of 2x4s sitting on top of the joists and sticking up to support the walkway, creating numerous thermal bridges through the ceiling.

In General questions | Asked By Adam Liberman | Sep 19 15
10 Answers

Comments on wall design, please

Attached is an image of a wall system I've conceptualized. It combines ease of interior electrical, plumbing, and wall finishing work with the structural benefits of CMU construction, the air tightness and performance benefits of a REMOTE wall, and the maintenance benefits of EIFS.

Looking for feedback. Any pitfalls with this approach? Overkill?


In General questions | Asked By Matt Culik | Aug 31 15
11 Answers

My old house came with a gas water heater that isn't venting

My old house came with a gas water heater that isn't venting; I need to replace it. Getting the venting right, even with a high efficiency, power exhaust, heater may be quite expensive. I am considering a heat pump electric. Has anyone done a comparison?

The house is big. Three floors with three bathrooms per floor. Our first-hour demand is maybe 50 gallons.

In Green products and materials | Asked By David Williams | Sep 18 15
6 Answers

Mini-split final install Qs

Hello All,

The info I've found in other threads regarding DIY mini-split installations have been invaluable, and I am very appreciative.

I am now at the stage in my own, 3 zone, install that it's time to pressure test, evacuate, and release the 410a. I purchased pro equipment to do the job and I just have a few lingering questions I'd like answers to, along with any advice, before proceeding.

In Mechanicals | Asked By Scott Mcllarky | Sep 17 15
28 Answers

Skipping radiant floor heat in a passive house?

I'm building a house with (conservative numbers) R 60 walls and R90 ceiling. The windows are in-swing casements with double seals. The floor is going to be stained concrete on 2" insulation. I had 2 consultants tell me that I will not need radiant floor heat it will be too much. We will have a whole house air circulation system and a gas fire place. I am worried about not putting in the pipes in the floor and then being wrong. I am considering just putting in the heated floor under the rooms away from the fire place. I could add a heater to my whole house ventilation system if needed.

In PassivHaus | Asked By Jenz Yoder | Aug 25 15
18 Answers

Mineral wool in double stud wall (and others)?

Hi All,

I am building a house in central VT (climate zone 6) and am liking several of the properties of mineral wool. Chiefly, since I'm DIY'ing, the cost is attractive. I have two wall sections in mind for this for which I've attached sketches below. So, on to my questions:

1. Double stud wall with mineral wool batts

This achieves R-30 with 2 layers of 3.5" mineral wool batts
The interior stud wall is structural and is also a service cavity

In Energy efficiency and durability | Asked By Jesse Anderson | Sep 16 15
10 Answers

Attic ceiling project

OK...read lots, know lots, but have a tough situation: 1924 unvented hot/cold attic, shallow rafters (4"), plank roof deck, asphalt shingles/tar paper and wishing to finish the attic space for office/play area. Previous owner installed very thin layer of foil faced batt against roof deck at least 15 years ago--no thermal impact, but more importantly there has been no moisture issues for the past 43 years (28 him, 15 me). I really don't want to go closed cell spray.

In General questions | Asked By Chris Haddox | May 29 15
3 Answers

Locally sourced wood siding in upstate New York

Reading through the QAs has convinced me to pursue locally sourced wood siding instead of vinyl siding. What trees from the area around upstate New York are best for durable siding? I'm thinking stained and sealed siding, rather than painted.


In Green products and materials | Asked By John Ranson | Sep 17 15
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