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4 Answers

Tyvek over foil-faced polyiso

I was looking a the spec sheets for foil faced polyisocyanurate and it gives an R value for the foam and then a R value of the foam with an air space. For example, the 3/4" foam has an R value of 5, but the R value of the foam with 3/4" reflective air space is 7.5. If I'm installing foam, covered in Tyvek then 3/4" furring strips with siding, do I have the reflective air space to get the R of 7.5 since the Tyvek is directly over the foil facing?

In General questions | Asked By E247 | May 19 18
4 Answers

Debating cavity insulation

I'm starting a house build in New Brunswick (Climate Zone 6A). My planned assembly has 3" of EPS foam on the exterior (3" Silverboard XS). I've already bought the Silverboard, so there's no going back now.

To please the local code officials, I will be installing Membrain on the interior.

In Energy efficiency and durability | Asked By Chris Burpee | May 18 18
2 Answers

Comfortbatt/Rockwool/Roxul and temporary compressibility

I have some framers coming tomorrow and have a basement wall being constructed inside the existing wall so as to insulate inside the stem wall. I'm planning on using rockwool comfortbatt at the bottom of the wall to allow for some breathability of the stem wall.

Will I be able to squeeze the 5.5" comfortbatt through a 3-3.5" wide opening (it will expand to full size, once in the wall)?

It hard to tell if it can compress that much, even intermittently, though I'm guessing so.

In Green products and materials | Asked By rossn1 | May 20 18
2 Answers

Over my head

I'm new to this forum, so I hope this is an appropriate question. I'm at the planning stage for a gut rehab of a ~2500 sq ft home in Boston, MA (which I think is zone 5). We're going to be completely rebuilding the envelope and replacing all the systems. We will have 14kW of solar on the roof.

In Mechanicals | Asked By Bradslees | May 19 18
1 Answer

Does the roof sheathing side in the attic space have to be insulated?

in some rooms in the upper levels there is attic space with an access door. I realize that the walls which are against the liveable space have to be insulated, but does the side with the roof sheathing have to be insulated? This is the side where the roof shingles are attached.

In Building Code Questions | Asked By C D | May 19 18
7 Answers

Sound transmission and ventilation

From a practical perspective the ideal ventilation system might be a fan (or HRV) connected by several very short runs to the rooms it serves.

Is there a point where the runs are too short and form a path for sound transmission between the rooms? Do the small ducts used by systems such as the Zender work better at preserving acoustical privacy? should the ducts be configured so they all enter the fan or core so that there is no shortcut for sound transmission?

In General questions | Asked By Malcolm Taylor | May 18 18
7 Answers

Cathedral ceiling and lights

We're building an ICF home with an unvented attic (rigid insulation over sheathing) and metal roof. The living room and kitchen will have a cathedral ceiling (roof 4:12 pitch). Living room will have a combination of sconces, pendants, LED strip lighting (indirect), and floor lamps.

The kitchen is another issue. The south wall will have two levels of windows with a counter and no overhead cabinets. We will have an island and plan to place pendants over the island. The north wall will have overhead cabinets with under-mount LED lights and LED strips for indirect lighting on top.

In Interior design | Asked By User-7022224 | May 18 18
2 Answers

High Sierra Showheads, any reviews

Hi,

We are building a pretty good house in Colorado, zone 6b. There will be a master bath with a curbless shower that will have a bench and also standing area. Separately we will have a tub shower combo. My husband likes both a regular shower head and hand held, in some configuration.

We would like all metal parts for their reliability, but the number of companies that offer that without charging loads of money is limited. Also water sense rated, low flow also is a preference. Any suggestions? I can across High Sierra Showerheads, any feedback from users?

Thanks in advance,
Lydia

In General questions | Asked By LYDIA SEGAL | May 19 18
1 Answer

How to insulate a gambrel roof?

I have a house with a gambrel roof and every year I have major ice dam issues as well as interior wall damage on the lower pitch on the second floor. I have attached a few pictures of the problem as well as photos of the original plan sheets.
I am in need of re-roofing the house this year and I would like to fix the problem.
Is there a fix? This rafters on this house are 2X4's.

In General questions | Asked By Darwyn Heme | May 18 18
8 Answers

“Picture frame” method for outie windows

i am installing outie windows in a house with 4” of exterior rigid insulation. the windows are all triple pane in the following sizes: 24” x 24”; 30” x 30”; and 32” x 64”. the method that i would like to use to install the windows is mentioned in the article http://www.greenbuildingadvisor.com/articles/dept/musings/installing-win... :

"Install a picture frame of 1x4 lumber, installed on the flat, on the exterior surface of the rigid foam. The 1x4 picture frame is screwed through the rigid foam to the sheathing and framing."

In Green building techniques | Asked By Loretta Gurr | Apr 28 18
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