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3 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
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
6 Answers

Water Testing After Pex Repipe

I live in South Orange County, California, a repiping companies paradise. A massive amount of newer homes are being forced to repipe due to copper failing and slab leaks. The pinhole leaks begin developing between 8 to 15 years after the home is built and sometimes sooner. The theory according to most is that the builders went cheap and installed copper M in the homes, while the water company uses cholormine which the Copper M can’t handle. Most repiping companies will recommend PEX A, but also market USA made Copper L for the repipe.

In Green products and materials | Asked By JohnZ99 | May 16 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


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,

In General questions | Asked By LYDIA SEGAL | May 19 18
7 Answers

Water heater pad

My HPWH is going in a tall crawlspace and I want to protect the base. Since it is going in before the crawlspoace is conditioned, I was thinking about using a condenser pad, but most of those top out at less than 400 lbs or load and my water heated will weigh roughly twice that when filled.

I found the Insulfoam water heater pad, but it is not available online from what I can tell.

What alternatives are there?

In Energy efficiency and durability | Asked By Norman Bunn | May 17 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
2 Answers

I'm not off the grid.. the grid's off me

We've had enough power outages here in the Hudson Valley that it is time to talk about unintentional "off-grid" living. To that end, I am interested in starting a discussion about the possibility of resiliency in high(re) performance homes. Some topics for conversation are:

  • What -if anything- can be run off off a battery? induction stove? ERV? Minisplit? Well pump?
  • How can a solar-power house be allowed to operate while the power is out - a grid cutoff?
  • What are other ways for a designer/homeowner to prepare for when they are unintentionally "off-grid"?
  • In Mechanicals | Asked By Ethan T ; Climate Zone 5A ; ~6000HDD | May 16 18
    4 Answers

    Frost-free hose bibb for a superinsulated house

    I can't be the first person to face this problem, but it feels like it because I can't see any product that addresses the problem. How the heck do you install a frost free hose bibb or sillcock without having a fitting inside the wall, when your wall is 21" thick? The longest one I can find is something like 16".

    In Mechanicals | Asked By Trevor Lambert | May 10 18
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