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14 Answers

Radon is 9.3 pCi/L even after radon mitigation — Is this OK?

Hi. I am having elevated ( 9.3 pCi/L) radon after mitigation done. I have an encapsulated crawl space ( insulated, air sealed, dehumidifier ) with piping running under vapor barrier-which terminates to an outside radon fan connected with a 4"PVC pipe. Would like to find out if it's Ok to install drainage ( perforated black pipe) piping under vapor barrier ( in encapsulated crawl) for radon mitigation. The piping is spilt off of a main trunk ( no continuous circle) to different sections under the crawl.

Asked By Hotandhumid | Jan 22 18
8 Answers

Avoid higher SHGC windows?


Asked By user-6994996 | Jan 22 18
6 Answers

Will installing a 12 x 18 inch grille between floors help my forced air flow?

I live in a 1800 ft2 NYC brownstone duplex. The two floor forced air system is inadequate to say the least for the first floor. It is 20 degrees colder on that floor. I have had HVAC professionals in and they have told me that there are NO returns on the first floor at all. All the supply vents are in the ceiling and with 12 ft. ceilings, heated air doesn't descend (despite fans) adequately. One HVAC guy suggested punching a rectangular grill (18 x 12 or larger) through the ceiling of the living room into the dedicated air handler closet in the master bedroom of the second floor.

Asked By Jcryder | Jan 15 18
1 Answer

Vinyl Windows with Synthetic Stone (2)

I posted this question last week, but it appears it was closed. We have Vinyl Windows installed, some with integral J Channel and some with Brick Molding and integral J Channel. On one wall of the home, we plan to instead install synthetic stone. I have been researching how best to use these windows with the stone.

I have contacted the stone manufacturer, and they had zero advice to offer. I also contacted the window manufacturer, and they have been no help either.

Asked By Kathleen J | Jan 15 18
1 Answer

Air sealing an old brick building

I’ve been reading with interest the posts on weatherizing old brick buildings, but I still have some specific questions I hope someone can answer.
I have a circa 1837 brick federal with double wythe walls in central Vermont. The bricks are hard fired with tight mortar joints and moisture from the outside is relatively well controlled. Exterior walls are strapped with 5/4” planks supporting the lath and plaster. Interior walls are the same 5/4” planking with lath and plaster on both sides.

Asked By duanegormanbuilder | Jan 13 18
8 Answers

Elephant in the room (kitchen, in this case)

Mechanical air exchange is rightfully part of every plan in energy-efficient buildings. A lot of effort and no small expense is devoted to choices of HRV or ERV balanced air. The house I am building is 3 bdrm. & 2,000 sq.ft., thus: ((2,000 sq. ft /100) x 3) + (4 x 7.5) = 90 CFM. And this is intermittent, i.e. not necessary during shoulder season months when windows are open (six months here in zone 4A), or during other months when the occupants are working all day or traveling for business.

Asked By David McNeely | Jan 7 18
1 Answer

When can I seal the basement floor?

I have just finished building my retirement home with energy efficiency, green products and products made in USA. The Basement is a conditioned space and is heated with a 9000 btu Mitsubishi minisplit.

Asked By Ron Flood | Dec 29 17
3 Answers

Can I build stormwater retention trench so I can park on top of it?

We are building on a small lot, and are required to locate a 10'x10'x2' stormwater retention trench in a location ideal for parking. I've been researching the base prep for permeable paving, and much of it looks similar to the stormwater retention trench: 12"-18" layers of triple washed gravel, overflow pipes, judicious use of filter cloth. Can anyone point out issues that would arise from doubling the base layer and otherwise building the stormwater retention area as we would a permeable driveway?

Asked By Bill Fitler | Dec 19 17
8 Answers

How do I insulate brick wall from the heated side of house?

I am working on a 1978 built, brick house in Juneau, Alaska. Was seeing moisture on drywall and some mold. After removing drywall found 2X2 nailers, 2 feet on center nailed at the grout line. Between the nailers was 1.5 inches of white bead board. Found a few places where the air was leaking in and believe that they have been taken care of.

Other info:
wall is above grade
appears to be single, standard size, red brick constructed wall

I am not sure how to much insulation can I add for the climate and not damage the brick?

Asked By Daniel Hall | Dec 17 17
11 Answers

Brick house insulation


My situation: I have a brick house, that initially had plaster and lathe walls. With the floor joists supported by inner wythe, and the joist ends embedded in the brick. I removed the plaster and restudded the walls with 2x4s.

My concern: On the lower floor, I insulated the stud bays with batt insulation. I thought this was a good thing, however, after reading your article I think I may have been mistaken.  I am beginning work on the second story and don't want to make matters worse.

Asked By 3rd Little Pig | Dec 9 17
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