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9 Answers

More rim joist insulating questions


I know this topic has been discussed a lot, but I cannot find exactly what I am looking for.

We have a 1926 Tudor in Minneapolis, MN. I am in the process of finishing our basement and I plan to use 2" of rigid foam on the walls and potentially between the joists to seal up the rim joist. I may use closed cell spray foam to seal the rim as well. My problem are:

1. We have concrete poured between our joist onto the foundation making it difficult to use rigid foam. The concrete is also poured very uneven. This is why I may use spray foam.

In Energy efficiency and durability | Asked By Joe Sweeney | Oct 25 16
1 Answer

Insulate rim joists with closed cell, with rigid foam on exterior?

I have a new construction home, zone 5. I wondered if you insulate the rims joists with closed cell foam, when we have 3" of rigid foam on the exterior?

In Energy efficiency and durability | Asked By Michael Brackett | Oct 26 16
2 Answers

Risky assembly

A friend called me today seeking advice for a new room he is adding to his brownstone. He has an unused space on the top floor and he wants to put a wine cellar there. A wine cellar on the top floor? Not an ideal location for sure. But just for kicks, let's assume he has no floor load issues and he can adequately insulate and seal the walls and floor. What about the roof? Did I mention this space is below and unvented flat roof? So drying to the outside is out of the question. I think the biggest concern is the sheathing.

In Energy efficiency and durability | Asked By Jonathan Lawrence CZ 4A New Jersey | Oct 25 16
7 Answers

How to insulate a stackboard house?

I have an old house, built in 1840, and with an addition put on around 1900 or so. The original house is stone, and the addition is made from stackboard. Stackboard is a technique locally popular in lumber towns, where you take rough cut 2x4s, stack them on their flat side, and chink in between with 1/2" chunks of wood. Essentially your entire wall is solid wood and you renovate using a chansaw (my grandfather actually did this apparently, as even the interior walls were done this way. it's wierd). The house is pretty much uninsulated other than the thickness of the walls (R1?)

In Energy efficiency and durability | Asked By Terry Sharpe | Jan 4 16
40 Answers

HRV duct set up

I am getting ready to install my HRV. I have been contemplating exhaust in the two bathrooms, three bedrooms, and kitchen area, with only one supply duct in the great room near my mini-split. 1300 square feet, one level, 3 1/2" exterior foam, 6" fiberglass batts, unvented sealed crawl space. The design person at the HRV store is said I should have supply to all bedrooms and just exhaust the bathrooms/kitchen. Climate Zone 7, so I am a little concerned about supplying all that fresh air to the bedrooms in the dead of winter.

In NAHB Class Discussion | Asked By Steve Vigoren | Sep 6 16
6 Answers

Sizing a heating and cooling system

We are finalizing designs for the mechanicals and I am looking for some advice. My mechanical engineer is doing all the Manual J, D, S, and HERS calculations. On my side, I am running the WUFI analysis. We are going to spec a combination of ducted, non-ducted units working off of a single VRF ASHP. Some of the questions I have are as follows:

1) Does anyone have any experience with regards to which sizing tool is more accurate in a very well insulated house, Manual J or WUFI?;

In Mechanicals | Asked By Jonathan Lawrence CZ 4A New Jersey | Oct 24 16
9 Answers

Heat with a minisplit in Ontario

I'm looking at replacing my HVAC system this year. I live near Peterborough Ontario. Currently my system is composed of a 60 year old oil boiler, a wood stove and portable AC units in bedrooms. I had previously asked a question http://www.greenbuildingadvisor.com/community/forum/mechanicals/98848/re... about a boiler.

Some information from that post that is relevant here:
Using bills for oil from last year I calculated my heating load (@ -4F) to be 22000 BTU/h. Basement, addition and main home have been spray foamed. There is R50 in the attic.

In Mechanicals | Asked By Joe McRae | Oct 23 16
2 Answers

Cedar siding installation

Ok..getting around to siding and what a nightmare trying to decide what to use for siding. We really would like a natural look and natural cedar comes in at about 1/2 the cost of LP smart siding and my understanding is smart siding is not installable over furring strips. I would like to install the cedar OVER the existing asbestos cement siding as to limit the massive labor and possible danger of removing the current siding. My questions are:
1. Do I have to locate the studs to mount the furring strips? The house is 135 years old and has 1" tng sheathing.

In Green building techniques | Asked By Geoffrey Cook | Oct 24 16
2 Answers

Insulating a flat ceiling in conjunction with a hot roof?

Hey there... My 950 sq ft. house has a hot roof insulated with 4.5" of spray foam. The roof system is 2x8 rafters with 2x6 collar ties. The attic space is basically a crawl space. I'm planning by adding insulation to the flat ceiling using 5.5" of rock wool. I currently have zero moisture issues in the house and heat with wood, generally keeping the house humidity pretty low. Am I doing anything bad by adding the insulation to the flat ceiling?

In Energy efficiency and durability | Asked By Todd Loiacono | Oct 23 16
1 Answer

Insulate attic to prevent pipes from freezing

Long story short: We have pipes running through the attic of our garage to an addition. The pipes run close to the roof line and then go down an outside wall. The attic rafters are not insulated and the walls above the ceiling line are also not insulated. The floor of the attic where it goes over the house is insulated. The attic portion is open to the garage itself (its kind of like a crawl space), but the pipes will freeze at anything below 32 degrees, so clearly heat is not getting up to the attic from either the garage or the house.

In General questions | Asked By Lindsey Carden | Oct 24 16
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