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1 Answer

Need recommendations for WP and breathable house wrap/air barrier products that are applicable to residential renovation.

Has anyone had recent experience with the Grace Vycor enV-S, which seems to be what I'm looking for? Thanks.

In Green products and materials | Asked By Gary Glines | Feb 5 15
9 Answers

Ducted HRV, Lunos e2 or Extraction only

Thanks in advance for your knowledgeable advice. I understand just enough about air sealing, heat recovery, and ventilation to be completely confused as the best way to go about ventilating the house I am currently building. This house is a very small (700 sq ft./64 m2) open plan, one bedroom/one bath strawbale house with a small loft and a simple raked ceiling. I am attempting to build it very tight, but won't have actual figures on that until after the first coat of render and blower door test in April or so. I do need to consider electrical runs and potential ducting now.

In Mechanicals | Asked By Enga Lokey | Feb 1 15
1 Answer

Air filter MERV "sweet spot"?

I'm looking at air filters for my new house and was wondering if anyone had found a "sweet spot" in the tradeoff between filtration efficiency and cost, or some way to calculate that, or maybe a rule of thumb?

In Mechanicals | Asked By Roy Goodwin | Feb 5 15
4 Answers

Is it possible to simply drill and loose fill my ceiling to improve efficiency?

I have a 1950's split level in northern VA. My upstairs is 5-10 degrees colder than the rest of the house. Thermostats are on the main level set to comfortable levels but if I try to get the top level to the correct temp, anyone downstairs will melt.

In Energy efficiency and durability | Asked By Erik Cecere | Feb 4 15
3 Answers

Creating a conditioned crawlspace/air sealing questions

I have a 1940's ranch in climate zone 5a (Northern NJ) that's a bit of a disaster from an energy efficiency standpoint. One step that I'd like to take in the near-term is to create a conditioned crawlspace and I have a few questions about the best approach to take.

In Green building techniques | Asked By Eric Barker | Feb 2 15
2 Answers

Follow-up question on cut & cobble rigid foam in rafters

Several weeks ago many of you were kind enough to offer advice on a cut & cobble insulation project I undertook while converting our old garage into a new master bedroom. A quick update on my progress. After three long weekends and a few extra hours here and there, I have 8" of polyiso foam board fully installed (one layer between the rafters, one layer beneath). Both layers are ~95%+ airsealed (I now need to find an effective way of locating any last remaining leaks). The room is still unheated but the difference is palpable.

In Energy efficiency and durability | Asked By Brian Gray | Feb 4 15
4 Answers

How to insulate a cathedral ceiling under an exposed metal roof?


In GBA Pro help | Asked By Jennifer Duffy | Feb 2 15
3 Answers

What size point of use water heater should be used to heat water for my washer?

I have a high efficiency Whirpool washer in my detached garage. I plan to use a tankless point of use water heater for those occasions when I need warm or hot water loads. What are the specification for a water heater to meet my needs?

In General questions | Asked By Trudy Urdal | Feb 4 15
13 Answers

What is the efficiency of gas powered infrared radiant heat?

My project: Climate zone 6A Hortonville, WI 54944 Energy source: electric or propane, no natural gas available

An earlier post about heating garage brought up the possibility of gas powered infrared radiant. I'm familiar with these devices, but I literally can't find any information from the manufacturers regarding their efficiency. They all claim to be "very efficient" for various reasons, but I can't find hard data.

Are they rated by a percent like house furnaces? I.E. Are they in the range of 80% efficient ceiling hung unit heaters?

In Mechanicals | Asked By Rick Van Handel | Nov 24 14
4 Answers

Tar used for interior concrete sealing

I'm in the middle of a residential new construction project, targeting Passive House requirements. It is an insulated slab on grade, double-wall stick built home, where the air barrier is on the outside/exterior wall. There is no vapor barrier, and there is an approx 20" cavity for dense-pack cellulose. We just finished air-sealing, and my builder coated the top of the concrete slab in between the double walls (20" of concrete) with 10 gallons of Henry's foundation coating. Of course, this is an exterior-grade product that contains tar and a lot of nasty VOC's.

In Green products and materials | Asked By Eric Merkt | Feb 2 15
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