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3 Answers

Details about drywall under tongue and groove as an air barrier

I have read often on gba about the importance of using an air barrier under tongue and groove and I may be over thinking it but it seems that 1/2" ultralight has the potential for more air leaks around nail penetrations due to occasional voids in ultralight and that 1/2" could more likely bust around nail penetrations and let air in versus 5/8" but before I wear myself out hanging 77 lb sheets I figured I should ask an expert.

Thanks,

Matt

Asked By Matthew Seabolt | Jul 1 15
5 Answers

How do I get and keep air out of my geothermal loop?

We have a "closed loop" geothermal heating and cooling system. 97 wells 300 ft. deep. 4 story building. 36 water source heat pumps. 72 electric water pumps. 219 ball valves.
There is no way at the high point (attic over 4 story) to release air and no easy way to add water to displace the air. The contractor keeps trying with their big pump and tank trailers to purge the system by driving the air bubbles out through the basement. No surprise to me, having observed the bubbles in my bathtub travelling upward, this approach keeps failing.

Asked By Todd Conradson | Jul 1 15
1 Answer

Dense-packed cellulose in exterior walls

I have a 100+ year old home and there is currently no insulation in the walls. There is vinyl siding on the exterior and I think it was installed over the old wood siding. I am considering having dense-packed cellulose blown into my 2x4 exterior walls. Am I going to have a moisture problem if I do so? I've read conflicting opinions. I would appreciate any advice you can offer.

Asked By T S | Jul 2 15
0 Answers

Intus finishes: Any chemists or PVC film experts out there?

About to get quotes for 2 jobs on Intus vinyl windows. Never heard of this technology and its pretty amazing how dark they are offering for some of their exterior color selections in vinyl. I will recommend staying on the lighter side to be safer but does anyone have any opinions on this film technology and color choices that Intus is using?

http://www.intuswindows.com/products/windows-u-pvc-arcade/

Click on "colors" for description of the film technology.

Asked By Brian Knight | Jul 2 15
4 Answers

Relative value of air sealing at exterior sheathing

I am trying to understand the relative value of air sealing at the sheathing. To do this lets consider cost as the benchmark. I realize that there is value beyond cost but this is an easily quantifiable benchmark and the one that seems most resonate with my clients.

Asked By Hugh Stearns | Jul 1 15
20 Answers

Foundation capillary break & waterproofing

My wife and I are building a small home (First Day Cottage) on a full foundation with a walkout on the downhill end. I read about having a capillary break between the footing and foundation wall and it makes sense to me. When I asked the concrete contractor about it he said he's never done it (though he did remember one other customer who asked about it a couple years back). I get the impression they won't leave me much time to do it myself between pours.

Asked By Martin Frank | Jun 30 15
16 Answers

It's 2015 and they still build like this...

Brand new build going up in Phoenix, AZ. What you see is completely 100% framed and ready for stucco. The missing OSB sheathing is done on purpose. They do "open framing" and only use sheathing where required. The rest is open 2x4 framing.

They will stuff R-13 batts within the 2x4 walls, staple on some building paper and then put 1" of rigid EPS on the outside and use conventional stucco to finish it off.

A recent blower door test on a home like this showed 15 air changes per hour.

ALL of the duct work and air handlers are installed in the 150F unconditioned attic.

Asked By Peter L | Jul 1 15
1 Answer

Boiler upgrade recommendation?

I’m currently looking to upgrade my old boiler as it developed a small crack and is leaking. My current boiler is a P-468U-wt (151,000 btu/hr) Weil-McClain oil-fired boiler with a 40-gallon hot water holding tank.

I’m getting two different suggestions from two of my plumbers and would love some input on their recommendations. One recommends replacing it with an Energy Kinetics System 2000 and the other one is suggesting a Navien Combi-boiler.

Asked By Joe Pavia | Jul 1 15
1 Answer

Where to put the water barrier?

Hi,
I'm going to retrofit rigid foam over a log home in Vermont. The logs are 6 inch pine logs, that have an R value of about 9, they have a clapboard cut on the outside so the house will not appear any different with a 3 inch layer of foam insulation with a rain screen and clapboard.

My question is about where to put the tyvek, on the out side of the foam or under the foam? We are replacing all the windows and doors. It would seem to me that the tyvek belongs on the outside of the foam and over the flanges of the new windows and doors.

Asked By Thomas Gardner | Jul 2 15
73 Answers

Geothermal nightmare

We truly hope you can help us. We had a geo-thermal closed loop system (into the river) put in and it went online March 2012. WaterFurnace Super DeHeater, 4 Multi-Aqua mini-splits (included for AC) and an air-handler (included for AC). 3200 sq ft home with baseboard and in-floor radiant heating. $34,000 and we have had nothing but problems.

Asked By Colleen Nicholson | May 30 13
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