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4 Answers

Relative humidity conundrum

I have an Aprilaire automatic humidifier installed in the return air duct of my HVAC.
The Aprilaire displays RH% and is presently set at maximum (5,000 s.f. home) because we have had a problem with our wood floors drying out too much during the winter. The conundrum is that, for example, when the Aprilaire displays 45% RH, my hand-held RH meter may display only 30% RH. The obvious check of using the same meter in the return duct air stream confirms that the Aprilkaire reading is correct. So how can the 2 readings be so different when the Aprilaire is reading the returning air stream?

Asked By Chris Simmons | May 5 15
1 Answer

Why should we shift to EPS panels for building construction instead of conventional methods?

I write this email with great respect for you. I was going through your a particular website on EPS technology and came across your profile. As I am myself a young engineer and doing research work on 3D EPS Panel. During my research i came across a few unanswered queries. I am from India and this technology is currently being used in filler walls only and not as load bearing structure, therefore i was wondering if you could help me in understanding the adaptability of this technology in advanced countries like yours as compared to India which is still a developing nation.

Asked By Sural Kaul | May 5 15
2 Answers

Deciding between power vent and chimney water tank

My current water tank is rusting, rental company screwed up and it rusted prematurely, when i replaced my chimney vent furnace with high efficiency i was told the "orphan" water tank may have back drafting issues which did not happen, but the water tank anode was already gone and it was rusting internally. I figured when the water tank was getting old 5-10 years from now i would go with dual pipe power vent but it died prematurely.

Asked By Alan B | May 4 15
5 Answers

Geothermal - Sizing Issues - 4 Ton or 5 Ton?

I live in Cincinnati, OH and I am zeroing in on purchasing a geothermal heat pump for my 5800 SF (conditioned) home. My home is all electric is currently heated by an 8 year old 4 ton air source heat pump with 15Kw electric backup. My issue is the two geothermal companies I have contacted to quote the job disagree on heating load of my home. Both companies did Manual J calculations, but are coming up with different numbers. One company has the heat load at 55k BTU -- says a 4 ton is the way to go. The other company has heat load at 68k BTU - says go with a 5 ton unit.

Asked By joel perrine | May 3 15
4 Answers

Open cell spray foam on roof deck & vapor retarding primer


Asked By David Amenhauser | May 4 15
1 Answer

Fixit 222 Aerogel

It was mentioned in the 2015 Passivhaus conference article, what is its cost and R value?

Asked By Alan B | May 4 15
2 Answers

Who do I contact or is analysis done here?

I have a new construction house that is designed and ready to be built.

I am satisfied with the layout, but need expert analysis on choosing the insulation and HVAC strategy.

I want someone to look specifically at my plans and advise me on this particular project. I am unsatisfied with the "spray foam seems to work well, or i sell a bunch of...." responses that I am getting.

Who performs this type of service? How do i find someone reputable?
Do I just upload plans here in another post?

I live in Northern NJ zone 5A.

Thank you for your help

Asked By Brian McDonald | May 4 15
2 Answers

Spray foam wall and 2x6 framing: How to seal stud-to-stud cracks?

I spray foamed my entire house. Roof trusses, wall cavity and even the floor.

We're just getting ready to do electrical and mechanical rough in and the spray foam guys are going to come back and scrape any exposed foam off the face of the studs, and also seal the windows and stud-to-stud area.

What they are planning on doing is using acousti seal where 2 studs sit side-by-side and then put tuck tape over the acousti seal.

Asked By Mark Helmrich | May 4 15
2 Answers

Spray foam covers entire 2x4 on roof truss...bad?

I had my roof deck sprayed with spray foam (to the underside of the truss). My roof trusses were designed at 16" OC and constructed with 2x4's. They needed to spray 4" of foam to get the code requirement for insulated value, so they covered the 2x4's completely on the roof deck.

Now I'd never really looked at and or thought about it till after they were done...(should have had the trusses designed with 2x6's) but the 2x4's are fully encapsulated with foam. I'm worried they are going to rot because they can not breath. Is is not a big "no-no" to encapsulate wooden studs?

Asked By Mark Helmrich | May 4 15
2 Answers

How can I seal this space w/ moisture in mind?

Hi All,

I am working on renovating our second floor which includes putting in a master bathroom and gutting and redoing an existing 2nd floor bath. It is a 1952 cape with brick siding on concrete block. The masonry walls are completely uninsulated in most cases. I have taken advice from the GBA site while researching various issues associated with this project and figured this would be a good place to ask about this.

Asked By G S | May 2 15
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