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4 Answers

Can Tyvek be used over fiberglass insulation that is falling out from between the roof rafters?

My parent's 1975 cape on the Vineyard has an unfinished second floor in which there is one occasionally used bedroom which has been sheet rocked. The rest of the attic is simply exposed fiberglass insulation between the rafters. In some places the insulation is falling out. Can we use Tyvek stapled to the rafters to keep the fiberglass in between the rafters and out of the atmosphere ( exposed fiberglass insulation is an irritant). Technically we want to keep the "attic an unfinished attic".

If Tyvek is not appropriate can we use the pink resin building paper?

In General questions | Asked By Ruth Cutler | Sep 27 16
5 Answers

How to encapsulate a brick veneer crawl space?

I am in the process of encapsulating our crawlspace and have a few questions. The house rests on concrete block piers and contains a brick veneer that covers the crawl space and extends below grade. There is a 2-3 inch air gap between the brick and the framing as well as the concrete blocks. The house is located in Climate Zone 3A so plenty of humid air.

Thus far I've installed a 12 mil vapor barrier over the dirt floor and up the sides of the brick wall (leaving a 3 inch gap for termite inspection). I've also closed up and sealed the vents.

In Energy efficiency and durability | Asked By Nate Wofford | Sep 27 16
6 Answers

Please help me pick the best option for HVAC replacement

We moved into this 20 year old house here in Nashville, TN in June and have been doing various projects to bring the home up to and above current building best practices. We have put open cell foam in the attic (average ~8 inches with rafters covered) and have encapsulated and foamed the crawl with 1.5 in of closed cell and 12 mil vapor barrier. We replaced the upstairs HVAC with a new 5 ton Trane xr17 and S9v2 furnace.

In Mechanicals | Asked By John Sexton | Sep 8 16
3 Answers

Do I have an issue?

The weather is my part of Zone 3 is still pretty hot (90s during the day with a cooling trend into the upper 80s). I noticed that my two year old air-source heat pump is struggling a bit to keep things comfortable. The thermostat upstairs is set for 77 degrees but the temperature is hovering around 81.

I also observed some wetness under my outdoor unit as well as some similar signs of water in the pan under the air handler. What do you guys think? Am I low on refrigerant? What might cause that?

In Mechanicals | Asked By Steve Knapp | Sep 26 16
15 Answers

How much are mini-splits really affected by altitude?

Hello -

I'm sizing a heat pump mini-split for my 20x20 garage, which has been pretty well air sealed and insulated with closed cell foam. I've had a series of installers out and the recommendations were all over the place, ranging from 12k to 18k BTU, and from $3k to $12k.

Two of the companies actually bothered to do a load calculation, and I tried it online as well - but those numbers had a broad range, too.

In General questions | Asked By Dave H | Sep 22 16
2 Answers

Use poly with Roxul (on ceiling)?

I am zone 4A, about 40 miles south of St Louis, Missouri. I am gutting my 1937 bungalow. It has two attic bedrooms (so it is a 1.5 story home), and it has an unvented attic. I want to leave it unvented, because of the multiple dormers. Eventually, the roof will be insulated with closed cell foam, but that will be a long ways off. I am not gutting the upstairs for quite a while. I have gutted the first floor and insulated the walls with Roxul R15 rock wool. I just ordered Roxul R30 to put in the first floor ceilings.

In General questions | Asked By Lonnie Sullivan | Sep 26 16
17 Answers

Quest for EPS

Finding extremely limited offering of eps rigid insulation in my region (upstate ny, north of Utica).
In my manufacturer search I found a product made by Cellofoam called Polyshield. They describe it as a sheathing product and it's eps with polymeric facers on both sides added for strength.
Is anyone familiar with this product?

In Green products and materials | Asked By Daniel F. Vellone | Sep 20 16
1 Answer

Video that aired on PBS: best practices for flange at bottom of window?


This is a video (link below) from the MN Building Performance Association, which aired as a half-hour special on PBS here in late 2015, I believe.
I am wondering if I'm misunderstanding something about proper flashing at the flange at the bottom of the new window that's being installed here. About six and a half minutes into this video, the installation gets going. The installer flashes properly before install, which I believe was the point of the new install, but then also tapes over the bottom flange. Is this correct?

In General questions | Asked By Minneapolis Disaster, 6B | Sep 26 16
7 Answers

Supplier for small registers and boots for ducted minisplit?

Hi all,

I have a completed manual J, S, D, & T. Now I have to find the different parts an pieces.

Because of the small loads in the house, the ducts and fittings are smaller than what I see in stock at the local big box suppliers. For example, I need 4x4 and 4x6 duct boots and register grilles. Where can I find those size fittings?

In Green products and materials | Asked By Clay Whitenack | Sep 26 16
5 Answers

Insulating underneath wood shingles underneath asphalt shingles


I've done my research and read quite a few relevant posts and articles here, but I couldn't find an exact match for my situation.

Legend has it that my home was built in 1876 in Philadelphia and moved here to Harrisburg via barge sometime after that. I'm in Climate Zone 5.

My wife and I are looking to build an insulated cathedral ceiling. Yes, I've read the wonderful GBA article :)

In GBA Pro help | Asked By Drew Buglione | Sep 20 16
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