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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
4 Answers

How to insulate the 'attic' of a 4' x 14' bump-out with hip roof.

This 100 year old house will be getting exterior insulation (3" SPF is current plan). The attic was insulated with SPF with venting for the underside of the roof deck. Intend to tie-in the attic SPF with the wall SPF therefore the soffits were removed.

There are 3 bump-outs that could compromise the continuous layer of of SPF that we plan to add. The largest is 4x14 (exterior wall size) and has a hip roof. It is currently insulated with pink fiberglass; seen from the eves. Likely done 20+ years ago when the last shingles were installed.

Asked By TIM LANGE | Jul 27 17
2 Answers

Pipe sleeve and under ground conduits through foundation : how big is too big?

I am building a slab foundation, with 4'6" frost walls and 24"X8" footings. The front corners of the house and garage are about 20 feet apart. I would like to sleeve the foundation walls so I can run conduits between the buildings, for future services. The questions:

(1) Ideally I want to run 3 separate 2.5" conduits between the building. As such, a 6" PVC sleeve through the 8" wall will not do. I will need an 8" sleeve. Is that too big for an 8" poured concrete wall with no rebar? Are there rules that determine how far up it has to be from the footing?

Asked By Mai Tai | Jul 26 17
6 Answers

Will R-70 cellulose sag ceiling drywall 24" o.c.?

My plans call for an R-70 ceiling of loose-pack cellulose in double-netted bays between trusses 24" o.c., with 5/8" Type X drywall holding it up as my air barrier. My installer says this will weigh about 2.55 lbs/sq/ft. Is this too much? Will it sag over time or pop screws? Do I need to use some special (expensive) low-sag drywall? I don't want to go to the expense and lost clearance of, e.g., an OSB layer above the drywall.

Anyone have experience with this?

Thanks.

Randy

Asked By Randy Jorgen | Jul 16 17
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