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1 Answer

Best choices for vapor barrier for a 1930s built home with dirt floor and partial full height crawl space?

Looking for best vendor for 10 mil poly ? Also has anyone ever laid down tile backer board as partial rat slab ? The poly alone is going to be a PITA . The house has stacked stone piers with some cmu block. When crawl spaces are difficult like this one , is power venting an option ? I want to keep it sealed , also there is no A/C ducts in crawl space. The project is Zone 5 Western NC.

In General questions | Asked By Greenconfusion | Aug 9 17
1 Answer

Mildew inside soffits


Facing a mildew/mold problem on a coastal home with unvented soffits. The painter has recommended sanding/refinishing the soffit boards using paint over an antimicrobial primer. The soffits are sealed off from the rest of the house with closed cell insulation. Should we be concerned about any remaining mold/mildew on the inside of the soffits?


In General questions | Asked By User-6868809 | Aug 9 17
1 Answer

How to detail vertical edge with stepped foundation

We’ve build a building in Costal Maine. The exterior is copper flashing, advantex sheathing, house wrap, rain screen and cedar shake. The building sits on a sloped lot. The foundation steps down the slope leading to vertical section of the exterior build up that are exposed. How should we detail this to make it look finished and not impede water movement. What we’ve done to date is caulk the joint between the concrete and the other layers. We are considering running a trim board along the edge and leaving the horizontal edges open to allow the rain screen behind the shake to breath.

In Green building techniques | Asked By Paul Tasillo | Aug 9 17
3 Answers

New bath fan vent placement - seeking advice

We have a first floor bathroom on the home's gable end that currently lacks a vent fan. I plan on installing one next weekend, but am seeking advice on the fan's exterior vent placement.

I think I have two options:

1) installing a ceiling fan and running a 12-ft rigid pipe through/parallel with the floor joists and out the back end's vinyl siding. This places the exhaust vent ~10-ft below my attic's soffit vents.

2) installing a thru-wall fan through exterior brick.

In General questions | Asked By hankla.lzo | Jul 24 17
10 Answers

Vented dryer depressurization and its effects on radon levels?

Has anyone studied the effects on radon levels caused by running a dryer, or other unbalanced ventilation equipment, in a well sealed home?

In Mechanicals | Asked By Calum Wilde | Jul 24 17
2 Answers

How to mitigate vapor migration thru an existing (1920s) slab on potentially contaminated soil ?

A client is considering purchasing an existing storefront building built in the 1920s.
A gas station with underground storage tanks existed 50 feet away from 1940-1985.
A Phase-I report has declared the tanks as potential hazards, with potentially contaminated soils and groundwater migrating to nearby properties, including ours.
To avoid the $10k Phase-II, is there a way to protect against the potential of harmful vapors from petroleum contaminants below the existing slab that likely has no vapor barrier by doing some kind of treatment above the slab?

In General questions | Asked By anarchitect | Aug 9 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.

In GBA Pro help | Asked By Mike Labesky | Jul 26 17
2 Answers

Need advice on ductwork in Florida condo: flex or ductboard?

I own a condo unit located near Sarasota Florida that was built in 1974. It is currently being remodeled and as part of that process (which involves removing drywall ceilings where the ducts are located) I want to improve on the current HVAC system, including reconfiguring and replacing ductwork.. To my surprise, I have found that the companies down here only offer flex duct (or if I really do not want flex then ductboard), but not sheet metal ducts (what I have in my home in Washington DC).

In Energy efficiency and durability | Asked By elizabeth hilder | Jul 26 17
2 Answers

French drain question on a small flat lot in high desert Idaho


In General questions | Asked By John Brown | Jul 26 17
4 Answers

Mold on inside of external OSB wall

Hello there,

Upon pulling a carpet in our newly-acquired home, I've noticed some mold under the window (1st pic).
After removing a piece of drywall I found what seems a big patch of mold on the inside of the exterior OSB wall. Interestingly, there is no mold on the fiberglass R-19 insulation.
There was no any vapor barrier or retarder behind the drywall and the house is in the climate zone 5.

What would be a proper course of action to proceed in this case?

In General questions | Asked By Dennis44 | Jul 27 17
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