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18 Answers

Insulating new construction home with no exterior rigid foam

Okay smarties, here is my scenario:
-I am Building a new home that is currently in the framing stage. 2x6 studs with Forcefield Sheathing (essentially same as ZIP).
-I am in in Climate 5 (iowa)
-My home is a California style architecture, 1.5 story, pitched roofs (now I realize why this is better suited for CA-vented roofs better option in Midwest!)
-My initial goal and how I came across these articles was to prevent mold (still is)

In Green building techniques | Asked By user-6809983 | Apr 9 17
2 Answers

Infinite R phase change materials

I am looking into using phase change materials in my new home to reduce temperature variability. It looks like National Gypsum's use of BASF's Micronal PCMs in its Thermacore drywall has never gotten off the ground.

I found Infiinite R via Google, but can't seem to find any independent reviews.

Does any one have any insight on this product or viable PCMs?


Climate Zone 3A - Upstate SC

In Energy efficiency and durability | Asked By Pnjfksx | Apr 23 17
28 Answers

Wall moisture monitoring

I'm diagnosing a tricky moisture issue. Part of the process has involved the use of wall cavity humidity and temperature probes. I have some data and I'd like to "peer review" some of the findings in broad strokes.

First off, this great article got me thinking:


In General questions | Asked By Rob Simpson | Mar 6 17
3 Answers

Modifying Existing ICF Walls

We are considering purchasing a house built completely with ICF walls. Our purchase is predicated on being able to expand windows in two areas and lengthening a current window area to install french doors to a deck. The expansion of the windows would involve removing the wall between two windows and installing a wider three panel window.

Is this possible with ICF construction. If so what are the key things that must be considered in making these modifications.


In Green building techniques | Asked By ledICF | Apr 22 17
3 Answers

Insulating under a raised floor

We are planning to build a timber-framed raised floor in one section of our house. Currently this section is 1-2 steps (7-14") below the main level of the house, and is slab on grade. Long ago this was a garage.

We live in central NY, climate zone 6.

The 1970-s vintage slab is totally uninsulated to the best of our knowledge. We will add a plastic vapor barrier above it before placing the raised floor framing.

In Energy efficiency and durability | Asked By David Hollman | Apr 15 17
24 Answers

Slim duct mini-split concerns

Hello, I've been getting all sorts of conflicting advice about using slim ducts. House is new construction in Massachusetts. second floor has three smallish bedrooms, about 600 sq ft in total. Heat and cooling load calcs support using an 18k slim to hit the three bedrooms, which aI have a contract with a firm to install. However, a couple of other firms have stated adamantly that the cfm rating of the unit is too low and we won't be happy. Thoughts?

In Mechanicals | Asked By George M | Apr 18 17
12 Answers

Choosing and balancing R-values

We are in Minnesota (Zone 6a). The home is an "L" shaped, 2200 sq/ft single level, slab on grade with a 28'x40' attached garage making the "L"

I'm looking to nail down the R-values of the wall, ceiling and slab. If we do a 10" double stud wall with dense pack cellulose (R30) and 4" of EPS (R20) for the FPSF...what should we aim for in the ceiling? Is there a formula or rule of thumb to follow to balance these?

We are thinking 8/12 pitch gable roof, 1' energy heel, and scissor trusses (3/12 interior pitch) over the 26 x 34 living room/kitchen/dining room area.

In Energy efficiency and durability | Asked By Scott K | Apr 20 17
4 Answers

Question on vapor retarder on interior dividing wall

First off, thanks to the many that respond to questions posted by us less experienced folks! I have learned a great deal from this site so thank you.

In General questions | Asked By James Culbertson | Apr 21 17
8 Answers

Heat build up in Florida garage

I friend of mine in Florida, zone 2A is trying to reduce the heat build up in his attached garage. He has a tiled, hip roof. I think he has soffit vents but no roof venting. There is a decorative half moon in a small gable above the garage door that maybe could be used as a gable vent.

He is looking at insulating either the garage ceiling or roof. He also mentioned a radiant barrier.

Being from the north, I suggested venting to let the heat our rather than insulation. What do you think would be the most cost effective and efficient way to help keep the garage cooler?

In General questions | Asked By jim sweazey | Apr 20 17
7 Answers

2/3 1/3 insulation rule in roof

Old build with flat wood deck on 2x13s. 4 inches Batt in joist space.(R12) 2 inch air space above batt insulation under wood deck No external vents into air space Adding polyiso on top of deck R 28. Before adding the polyiso can/should we put a separator sheet or vapour barrier on top of the wood as there is more than 2/3 the insulating value above the deck There is a poly vb above the drywall ceiling below e joists.

In GBA Pro help | Asked By UBSC | Apr 19 17
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