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8 Answers

New house build, SIPs?

New member here, we are planning to build a new house this summer and I'm exploring my options for wall systems. I plan to do the framing myself. House will be roughly 2500 sqft in Ottawa, Ontario Canada. Not the coldest place to build but not far off, and just for kicks it gets pretty hot and fairly humid here in summer as well.

In Green products and materials | Asked By Lance Peters | Jan 15 17
0 Answers

Standard (non-custom) window sizes?

In the interest of getting the "most bang for my buck," I have been trying to find "standard window sizes," as opposed to what is generally advertised as "custom" windows... Perhaps this is something that is available in high performance windows, perhaps at widths which correspond to common framing widths such as 24" OC, 16" OC, etc. I would be happy to design around these parameters, but it seems that most high performance window manufacturers also tout "custom sizes." Does anyone have a lead on standard high performance window sizing?

In Green products and materials | Asked By Ethan T ; Climate Zone 5A ; ~6000HDD | Apr 24 17
3 Answers

XPS foam on exterior side of window and door headers

I think have seen a similar question before but wanted to refresh.

Assume building a 2x6 wall. Using Mineral Wool for insulation (which means a smart membrane on the interior side of the wall). When framing headers for doors and windows almost ALL of them only need double 2x8, typically with ply sandwiched to make them flush with the stud depth. In 2x6, simply 3 pieces of header lumber are nailed together to get the 5.5" thickness of the stud.

In Green building techniques | Asked By Nicholas C | Apr 23 17
9 Answers

Gas heated steam radiator system


In Mechanicals | Asked By Daniel Herskowitz | Dec 5 13
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
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