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9 Answers

Building science options

looking for advice on options on getting into building science & green renovation ---- it seems there is still a disconnect between the building science research and the builders in the field.

Quick background on me --- I have a Chemistry degree and taught the subject for 8 years before leaving the field to be a remodeling contractor --- so I am very interested in the science behind renovating from an energy standpoint.

In Green building techniques | Asked By Jason Schatz | Oct 5 14
4 Answers

Adding outside air vent to existing HVAC?

Hi all,

I live in Los Angeles and dislike AC. We have AC on the second floor of our home, but in the evening when the outside air is down to a lovely 68-70 degrees, our inside air is still 85. My wife wants to put on the AC. I want to bring in outside air. But simply opening the windows doesn't really work well. What I really want is to integrate an outside air vent into our HVAC system, thus pulling out the inside air and replacing it with outside air. Trouble is, I don't know even what this would be called, so I can't seem to find any information on it by googling.

In General questions | Asked By Franz Metcalf | Oct 8 14
5 Answers

Retrofitting new wall inside existing frame

I have an interesting challenge in my 1941 1500SQFT energy retrofit in Minneapolis (Zone 6-7). I want to maximize realistic R-value while preserving the existing siding and sheathing, which we can assume has no vapor barrier (this will be verified when we open it up). While I would normally prefer to wrap the exterior, this is not possible at this time. There is no historic value to the plaster/sheetrock, and we're demoing kitchen and bath anyway, so I intend to do all insulation from the inside. The home is all 2x4 16"OC construction with old yellow fiberglass batts.

In PassivHaus | Asked By Ryan Griffin | Oct 8 14
7 Answers

US triple pane with uncoated glass?

I've been thinking that for the shaded south side of my Minneapolis home, triple panes with no Low-E coating might be best. I'm looking for a US made window that's decently insulated with high SHGC. I've asked a few manufacturers if they would make me a triple pane with clear glass, but I haven't found anyone willing to do this. Would I be giving up too much insulating performance (or interior heat reflectivity) with clear glass, and is the a US maker who will do this?


In PassivHaus | Asked By Ryan Griffin | Oct 5 14
3 Answers

Surface 4 low-e... condensation issues?

Your articles from April 2013, reference the issue of higher condensation on surface 4 using low-e products like i81.
Is there an update on this surface 4 condensation issue with the new i89 material.

In Energy efficiency and durability | Asked By paul holzsc | Oct 8 14
5 Answers

Audio podcast similar to GBA content?


I'm interested in GBA like podcasts that GBA members find worthwhile. Sometimes all I'm doing is sanding or grinding and can multitask effectively with good building related podcast.

Thank you,

In General questions | Asked By scott plantier | Jul 10 14
5 Answers

Avoiding spray foam in basement sills

I've been working with an energy auditor and insulation contractor to seal up our home in climate zone 5b. I've been told the only option for sealing the basement sills in this climate is spray foam. I am really trying to avoid this product entirely, and want to find alternatives. I have access to attractively priced reclaimed foil-face polyiso rigid foam, butI I've heard lots of negatives about cutting this stuff in to rafter and stud bays, in terms of blockage of moisture. However, can I block it in with the foil facing inward?

In Energy efficiency and durability | Asked By Asa Bradford | Oct 7 14
2 Answers

Interior air sealing and tongue & groove in weekend cabin

Zone 3, central/south Georgia hot/humid climate 300 sq. ft. weekend cabin with wall unit a/c, on piers (2x10 joists w/R30) with 2x6 stud walls; R19 fiberglass batts; good attention to caulking all seams/cracks and can spray foam around windows, door, penetrations; 1/2" plywood sheathing, 1/2" Rmax; weathermate plus housewrap, then finally cement board siding. Toilet, shower and sink with vent through the exterior wall. This will be a weekend getaway place - not lived in for more than a few days at a time. No washing machine.

In General questions | Asked By Brad Skeeters | Oct 8 14
4 Answers

We have an old concrete block house that was built in the 50's. What is the best way to insulate and side it?

My grandpa built our house and used a concrete block for the exterior. I don't believe there is much insulation between the drywall and the block and I don't believe that the block was filled with concrete. It is most likely hollow.

We want to add new windows and place siding on the exterior and were thinking of adding furring strips and foam board underneath the insulation but I am worried about the moisture factor. Please advise. (The basement is also uninsulated, unfinished, and is concrete block).
We are located in Montana.

In GBA Pro help | Asked By D B | Oct 7 14
2 Answers

.... alternative fuels heating price calculator ...

Periodically I run the local numbers on EIA.gov's Heating Fuel Comparison Calculator to make my self feel both good or bad. The comparative cost per BTU of wood heat still makes me feel good since I have an efficient Jotul F100 wood stove in my pretty-well insulated and very airtight house. The price of propane BTU's makes me feel less good although I run a very efficient hydronic system using a Triangle Tube boiler (Elite).

Open up this excel program and put in your local numbers. After you put the local price in the column for each fuel type, click on .

In General questions | Asked By flitch plate | Oct 8 14
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