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6 Answers

Has anyone tested charcoal furnace filters to see if they have an appreciable benefit in indoor air quality?

In commercial settings charcoal filters have been used for years to help eliminate odors and harmful gas particles. While I don't understand the science behind them, charcoal filters attract small gas molecules that would otherwise pass through even a Hepa filter.

I don't know how effective the furnace filters would be, as they can't be overly thick, but I would presume it might work to capture some of the off-gassing polutants? Cartridge style respirators use a rather thin filter and are effective, so who knows.

In Green products and materials | Asked By Rick Van Handel | Apr 28 14
2 Answers

When Cellulose Insulation is subjected to moisture or disturbed after being blown in, how is it affected?

We hired a contractor in Canada to replace insulation in our attic when a roof patch opened up under an ice dam in 2011. They removed batt insulation and replaced it with blown in cellulose fibre insulation. When they blew in cellulose insulation they did not connect the new bathroom vent hoses they supplied or seal pot lights below the vapour barrier and this is an extreme winter weather climate. This spring, the insulation was disturbed in order to determine the source of water causing damage to the drywall in the room beneath this space.

In GBA Pro help | Asked By Susan Bly | May 19 14
15 Answers

Using insulation board on top of OSB and under siding

I have a 1500 square foot house with a 500 square foot bonus room upstairs. I have a downstairs window that is broken and I need to replace. It is a vinyle window with a nailing flange.

I live in southern Kentucky (42206). My house has 2x4 walls with fiberglass batts in all walls including the interior walls.

I have osb outside walls with no tyvec or anything on them. Nailed directly to the osb is vinyle siding.

In General questions | Asked By don gilbert | May 15 14
1 Answer

Energy efficient heating and cooling questions

My house was built around 1998. I have the same split system heating/air conditioner with propane heat and water heater.

My system works fine. I actually prefer a propane water heater with a family of four because it can keep up better and still works during a power outage. (I live in the country)

I am wanting to reduce as much as possible utility costs. I was debating installing a more efficient unit myself.

In General questions | Asked By don gilbert | May 19 14
1 Answer

Ice and Water Shield on unheated garage roof

Hi. This may be a silly question, but I am wondering whether ice and water shield is recommended for the eaves of an unheated garage? Also, is there typically a minimum distance from the drip edge on the house's roof decking? I've come across 2' beyond the exterior wall? Grace makes an "HT" version. They claim that it is used for metal roof applications. Is this necessary in my case; Maine and light colored metal roof? Thanks.

In General questions | Asked By Matthew Michaud | May 18 14
5 Answers

Can one place rigid foam over existing panel siding?

I recently purchased a '70s modified A-Frame cabin at Lake Tahoe w/ 2x4 framing.
The exterior walls are constructed with vertical 4x8 redwood panels directly nailed to the studs.
There is no insulation.
The interior walls are sheet rock covered with '70s simulated walnut paneling.
The windows are single pane sliding aluminum framed,
as are the two sliding glass deck doors.
The structure is 24' x36', 2br/2bath, loft...1200sqft.
The county building dept requires permits and retrofitting to replace siding to the studs.

In Energy efficiency and durability | Asked By Whitney Johnson | May 17 14
6 Answers

When adding foam insulation to a roof assembly, is there any reason to bring it significantly past the exterior building line?

The assembly I am asking about is:
I joist rafters filled with dense pack cellulose/sheathing/4" polyiso/sheathing/waterproofing/metal roofing.
Is it ok to stop the foam layer at the building/insulation line to save material on the gable and eave overhangs?

In Green building techniques | Asked By stefan straka | May 17 14
1 Answer

1980 isolated gain passive solar with sunspace and crawlspace

We are considering purchasing a passive solar home built in 1980 from reclaimed lumber and glass with isolated sunspace. The home is 2 story 1700 sf open floor plan. It has windows on all sides, upstairs have been replaced with newer double pane but downstairs are original. They seem to be 2 panes of glassheld in a frame with very durable adhesive. Sunspace on S side is single pane glass and brick floor w about 1/2 of 5 x 20 sf area taken up by planting bed/soil. The top of it is slanted and is also glass, and had shade cloth on it. Access to about 3 ft. crawlspace is from sunspace.

In Energy efficiency and durability | Asked By Susan Geer | May 18 14
9 Answers

Poor attic ventilation, a.k.a. mold on rafters

Hello all,
Here are the basic details:

- I have a 23 year old 2-story frame house in the mid-Atlantic region (Zone 5). The roof was replaced last year, and there is a ridge vent, soffit vents at intervals and baffles inside the attic to allow unimpeded air flow into the attic.
- The bathroom exhaust fans are vented off to side camp vent on the side off the house. Though the fans seem to be running, I have a serious suspicion that they aren't actually pulling in anything.

In GBA Pro help | Asked By Kach Kidibba | Apr 23 14
4 Answers

Spruce versus pine species for exterior siding

Hi. I was originally planning on using horizontally placed pine boards for my house siding. Due to the time of year, there is a shortage of local pine and will not be accessible in the time frame I need. My local wood mill can provide spruce. He's used it on his house and it has held up nicely. My plan is to back prime and use a solid stain on the exterior regardless of species (and use 3/4" strapping behind it. Any experience with using spruce, its qualities and characteristics and is it good for this type of application? Thanks.

In Green products and materials | Asked By Matthew Michaud | May 16 14
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