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18 Answers

Insulation retrofit

Looking for some advice on a smallish rehab project I am about to start. I've read many of the great articles and Q&A discussions here, so I think have bit of direction...but as I am novice, I am interested in some feedback before I moved forward.

Asked By Jeremy Kachejian | Jan 12 17
4 Answers

Ridge vents: are they susceptible to snow drifts and driving rain?

My current design incorporates ridge vents with simple gable roofs (both house and garage).

It seemed to be both the aesthetic and performance choice. I will be using standing seam steel roofing, which seems to have a very water tight ridge vent design.

Asked By Mai Tai | Aug 17 17
4 Answers

How do I solve a backdraft issue in an airtight house with a three flue chimney?

There is a wood stove in the basement, a fireplace in the living room and a BBQ place in the kitchen. Each has their own flue. When I light a fire in the fireplace, it draws air back into the house through the BBQ flue. If I open a window in the dining room, it stops drawing air down that flue. Unless there is a wind out of the North West, then it is still a problem. Smoke from the chimney flue goes up and out and then gets sucked back in the BBQ flue and comes out in the kitchen.

Asked By Luke Thompson | Jul 30 17
14 Answers

AC register condensation: Not enough ridge for adequate ridge ventilation?

I'm living in the Houston area (zone 2) and noticed water leaking from some AC registers yesterday. The home is 9 years old, 300 sq ft.

The flexible ductwork is insulated.
The register boots are insulated, and the insulation has a lot of mold. (pic attached)
There is significant water in the attic on the blown in insulation around the duct boots: not damp, really wet.
I do not think the register boots are leaking, but I guess they could have small leaks.

Asked By Mark McFarlane | Aug 14 17
8 Answers

550' main water line to house : help me choose a suitable pipe

My driveway is 550' long, and the water meter is at the road. So far I have determined I should be happy with a 1.5" ID pipe, for the flow I am considering. I was all set to pull the trigger on HDPE pipe (NSF rated, 200 PSI), until I read some articles that claim this type of pipe becomes brittle with time when exposed to water disinfectants (read chlorine, chloramine, chlorine dioxide etc.), anything the utility puts in the the great lakes water to make it "safe".

So back to the drawing board. The options:

HDPE CTS 200 PSI pipe

Asked By Mai Tai | Aug 10 17
9 Answers

Floor truss spacing and sub-floor options for a "stiff" floor : opinions?

I am currently building a slab on grade home, with 24" deep open web floor trusses (24" selected with the intent of having (2) 20x21" house long chases to run low velocity HVAC ducts, supply and return and avoid bulkheads).

My architect, who is admittedly old school/conservative, specified spacing at 16" OC, with 3/4" ply sub-floor. The house is 30' wide, and the joists are basically designed to take this full span. However, I have a mid width supporting wall/beam in the design, which basically cuts the span in half (max span from wall to exterior wall is 17').

Asked By Mai Tai | Aug 5 17
7 Answers

Vapor drive and porcelain tile exterior walls

The nice thing about building a house on one's own is that the building gives you feedback before the finishing touches lock things in. One such lesson for me is summertime vapor drive. I have had Durock CBUs installed over vertical 1x3 furring for some time now with plans to install veneer stone later. The rainscreen gap is ventilated below and above and the insulation behind is closed cell spray foam, so no moisture drives into the house.

Asked By Edward Mallett | Jul 24 17
2 Answers

What is the best way to treat the main level floor on a coastal home elevated on pilings?

I have a client who has a bay front home on the eastern shore of Virginia that is built on pilings that put the bottom of the main level framing about 10' off the ground. The majority of this space has been enclosed for parking and storage and houses the base of an elevator shaft. There are codes dictating the construction of these in-fill spaces limiting their connectivity to the structural elements of the elevated house. The concept is that storm surge or shore erosion damage would be isolated to this space.

Asked By Mike Labesky | Jul 26 17
1 Answer

Radon Mitigation Question (Tu Tuff Liner)

I am working on a design of a small (12' x 16' -- 192 sq ft) workshop with a crawlspace that will most likely need some kind of radon mitigation plan. I definitely understand the details and "strategy" of initially putting in the perforated pipe and riser, then capping it so that a "passive" system is in place. If the picocurie readings are high, then one is in a good situation to finish the system or make it an "active" system with an inline fan. My question is this.

Asked By John Brown | Aug 4 17
1 Answer

Insulating half a roof, from the top. What to use?

Location is climate zone 6.

Have a home with straight gable. The client wants to replace just one side of his roof/ceiling with new insulation. Attached is a photo of what the previous contractor did on the other half of the roof. Roof/ceiling is cathedral and thus the only space available is rafter bays/ possibly adding insulation on top of rafters. The roof must be accessed from the top after removing the sheet metal. With such limited options (and only being able to improve half the roof) what would be my best option for insulation/improving this bad situation?

Asked By Brad Allen | Aug 5 17
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