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4 Answers

My favorite radiant barrier ad

This one is fun: It's an ad on GBA, placed by a radiant barrier manufacturer. The only problem is that they misspelled "radiant."


In General questions | Asked By Martin Holladay | Dec 29 15
2 Answers

Insulating crawlspace floor joists vs. walls

We have a home near Raleigh, NC. The home was built in the 1970s on a vented crawlspace on sandy soil. It has batt insulation between the floor joists. The rim joist and the sill plate are untreated lumber on block walls with 2 courses of brick at top of the block.

The crawl space has had moisture problems which have been largely addressed with plastic moisture barrier and 2 sump pumps with perimeter drain and a dehumidifier. There is indication of previous termite problems in rim joist and sill at front and back door but no apparent problems elsewhere.

In GBA Pro help | Asked By Beth | Dec 29 15
29 Answers

Makeup air for a wood-burning fireplace in a tight home

I am building a tight home with air sealing, R75 cellulose in cold attic floor, excellent Marvin windows, southern exposure and min-splits for heat and cooling. No gas appliances. We intend on using an ERV (Ultimateair) but we have one major extravagance: a Rumford masonry fireplace.

In General questions | Asked By Joe Suhrada | Oct 16 15
6 Answers

Insulated / Airsealed Garage Curtain Wall?

Hello, I'm wondering if anyone has experience with an insulated curtain wall to divide a workshop space from the rest of a garage. While the whole garage is to be insulated, it's really just the back 16 x 22ft area that really needs to be comfortable to work in. I thought that this may be easier to air seal because there are no doors to deal with. It would still be used for vehicle storage, so it would have to be very easily moved. Translucent would be great too, but not required. Does anything like this exist at a reasonable price?

In Green products and materials | Asked By Ryan Griffin | Dec 28 15
6 Answers

I would be most appreciative for any of your experiences or preferences between Faswall versus typical ICFs.

I’m planning a rural build in Southern Oregon --zone 4C– passive solar 2100 sq. ft. modular on conditioned crawlspace 2-3 feet high. The crawl which will act as a plenum will be insulated below the rat slab with EPS and it appears that ICFs and Faswall offer roughly the same R-value for through wall heat loss. I am trying to avoid EPS or XPS (unless encapsulated under the slab) due to their environmental negatives, possible out-gassing and fire risk. I am also concerned with potential insect issues with borers into the ICFs but will be parging the exterior surfaces of either product type.

In Green products and materials | Asked By ALAN Hart-McArthur | Dec 28 15
5 Answers

Need advice for insulating an attic and crawl space of an addition in Region 5 and using area for storage

Live in the region 5, Poconos / northeast Pennsylvania. There was an addition put on my 1968 cape cod style house, with a sunken living room with a fireplace, over a crawl space that is adjacent and accessible from my full basement. Then there's a 2 car garage next to that, on a slab. There is a pulldown staircase in the garage, and then there is a fairly large vented attic that run over both the garage and the sunken living room. With the fireplace chimney coming up between the 2.

In General questions | Asked By Ryan | Dec 27 15
1 Answer

Is it possible to determine the R-value of windows with an IR thermometer?

I have 10-year-old vinyl windows and have tried e-mailing the manufacturer to no reply, and i have an IR temperature reader.

If one knows the outdoor temperature, indoor temperature, and glass temperature, can that data be used to determine its R value?

For example, right now indoor is 20.5 C, outdoor is -4 C and the windows are registering 13.7 C on the temp reader.

The vinyl frame is about the same temp, maybe 0.3 C higher.

In Energy efficiency and durability | Asked By Alan | Dec 28 15
17 Answers

Heating and finishing a basement in a well-insulated house

Hi Everyone,

3 years ago I built my own house using techniques from this site, and now I need to finish the basement I built for my quadripeligic brother in law who has to move in with us. The basement is a walk out under a gambrel colonial that is highly insulated. The home construction was doing using dual exterior walls and filling the space with a combination of closed cell spray foam and cellulose insulation. I heat my entire 2000sq foot home with two Mitsubishi mini splits.

In Green building techniques | Asked By Denis | Dec 1 15
8 Answers

Insulating existing plastered basement wall

Is there a way that will not create a moisture problem to insulate over an existing furred out plaster wall in a basement and drywall over? I have been reading about polyiso, xps, and closed cell foam from http://www.greenbuildingadvisor.com/blogs/dept/musings/how-insulate-base.... What product would you recommend and why? There is no electrical on these walls. Or plumbing. There are two plastered walls over furring with plaster ceiling in a corner of basement. I might want to add a few outlets in this process. I'm trying to insulate the room to make it more comfortable.

In Green building techniques | Asked By Michael Kendall | Dec 28 15
13 Answers

Moved to a new house - evidence of moisture problems. What are my options?

Hey folks (hope I posted this to the correct area)!

I recently moved to a 1970s ranch style home in northeastern Wisconsin (by the big lake). Our summer and shoulder seasons are quite humid, and of course we have the infamous cold winters. The house has electric baseboard heat and a recently installed ERV system. The place was used as a vacation home with occupants only around in the summer months. Some of the baseboard thermostats were busted and running too hot. For A/C, it has a few sleeve/wall air conditioners.

In Mechanicals | Asked By Sean L | Dec 26 15
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