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1 Answer

Insulating a sloped ceiling

I have a 1.5 story home built in 1900 in southern NH. Minimal insulation on attic floor and some stuffed into the sloped ceiling from the attic. The insulation contractors that have looked at it want to dense pack the bays on the sloped part with cellulose. One said he could flash it with spray foam to seal it first, then dense pack. I have read that insulating with no venting is a bad idea. I understand without ripping the drywall down, it would be very difficult to insulate properly and add vent chutes.

In Energy efficiency and durability | Asked By Frank Mengler | Jul 22 16
2 Answers

Replacing insulation in basement

Hello, I have a 3 year old basment with 8ft concrete walls that was finished with 2 by 4's that are about 1/2 inch off the concrete wall and fiberglass batting was used as insulation which I don't believe is the correct material. If i want to replace this should i go back to the studs and perhaps do a spray insulation or is it best to take everything out and start afresh. At this point i do not have any mold/smell issues but also think it could just be better insulated. I am in zone 5/6, right on the edge. Thank you.

In Green building techniques | Asked By J D | Jul 21 16
2 Answers

Exterior and interior foundation insulation crossover

Hey All,
In the process of adding exterior insulation to foundation wall but am having an issue in a spot in the backyard where there is a new patio and front yard with a deck. My wife would rather i not rip out a brand new patio and new deck to insulate the foundation. So i was wondering if it would be better then nothing to in those areas put the insulation on the interior of the block and just have an overlap of say 10 feet where there is both exterior and interior insulation?


In Energy efficiency and durability | Asked By Chris King | Jul 22 16
4 Answers

Will this rainscreen assembly work for this application?

I am building a tiny house on wheels and I wanted to have a rain screen included. I would just like to use a mesh product for ease of installation and fastening options later.

I live in southeastern South Dakota. I will be using a 1" standing seam metal roof with a 5/8:12 pitch.

I have included a rough sketch and was wondering if it would work to have a continuous and connected wall and roof rain/vent screen?

In General questions | Asked By Damon Beck | Jul 21 16
7 Answers

Solar Water Behind a Window

First a quick back story: I live in Halifax, Nova Scotia, which to my knowledge is zone 5...? I'm getting condensation on my cold water pipes, where the pipes first enter my house from my well. In another question about this issue, Charlie Sullivan was kind enough to offer a suggestion of using a drain water heat recovery unit to preheat the cold water. Which, really is a great suggestion as it's 100% passive.

In Mechanicals | Asked By Calum Wilde | Jul 21 16
2 Answers

You told someone that they could patch open cell foam insulation with

You told someone that they could patch open cell foam insulation with spray insulation from the hdw store. The spray "stuff" that I am familiar with is of the closed cell variety. Is it that to which you are referring? Please advise, as I have some holes that need repairing.

In Green products and materials | Asked By Kenneth Sayers | Jul 21 16
8 Answers

Deck frame: cedar vs. steel

I am interested in opinions on whether northern white cedar is a good material to use for a deck frame. I've heard opinions that it actually lasts longer than pressure treated pine, but also doubts about using it structurally. I would protect the tops of the joists with some kind of flashing, as that seems to be where wood decks rot, and upsize the joists as called for in structural tables for the lower strength.

In Green products and materials | Asked By Charlie Sullivan | Jul 21 16
1 Answer

Exterior foam over 2 layers of siding a bad idea?

Zone 7, 100 year old house has 2 layers of siding. The original siding has lead paint of course. The outer siding won't hold paint. Was insulated in the 70s with formaldehyde foam injected into the wall cavities. Current plan is to use SPF as external insulation, using vertical furring strips embedded in the SPF to secure the new siding. The inner siding has a 4" reveal while the outer is more like 12" reveal. There are vertical furring strips between the 2 layers of siding which creates an air gap.

In Energy efficiency and durability | Asked By Tim Lange | Jul 21 16
15 Answers

Houston home

A would appreciate advice on a home about to be constructed in Houston, TX.

What would be best materials to use for:

1. Exterior walls. Would R19 walls be considered good?
2. Attic (Insulation underneath the roof or on top of ceiling)? Is Foam insulation recommended, if so what would work best?
3. Roof: would a metal roof be a good idea?
4. HVAC. Are minisplits recommended? Would supplemental heating be required if a heat pump is installed?

In GBA Pro help | Asked By Venkat Y | Jul 21 16
3 Answers

Net zero is not expensive?

I'm having a home built and am trying to go net zero with PV and an all electric home. The solar guy and some contractors are very surprised when I say it can be done with 4 kw of panels and fairly standard construction and heating system. I'd like to run my numbers by the wise advisers here and you can tell me if I'm wrong.

In Mechanicals | Asked By Brad H | Jul 20 16
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