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8 Answers

Vapor barrier

Hi. I live in Houston and unfortunately bought a house that has some issues with water penetration in several areas due to brick parapets extending above the roofline that were never capped. The biggest area of water entry is in the master bath which we have completely gutted down to the studs - several of which have to be replaced due to rot and deterioration over many years.

In General questions | Asked By Beth Puyau | Jun 23 15
2 Answers

California heating question

I have a 1910 craftsman home in the Bay Area where we might need cooling 4 or 5 days year and it typically does not get too cold. We are redoing the basement (seismic) and attic (new roof, beefed up framing) and will install a solar PV system. I will most likely go to a heat pump water heater and a new heating system (presently have floor furnaces). I am thinking about a mini split system or a ducted heat pump system with the ducts in the attic. What are the advantages and disadvantages to both? The house is 3 bedrooms and about 1800 square feet.

In Mechanicals | Asked By rob manheimer | Jun 29 15
4 Answers

An article for people who start from "I trust the contractor; he's a professional"


Props to all the excellent, diligent, hardworking contractors out there. That said:

Where's the excellent introductory article on this or another site (which probably already exists) to which I can point an acquaintance, about the value of due diligence in insulation/airsealing plans & not assuming a contractor will do an awesome job because they think that's what inspection mandates?

In General questions | Asked By Minneapolis Disaster, 6B | Jun 29 15
6 Answers

Window Flashing + Installation

Does this method / install look ok? More windows need to be installed and I am looking for improvements.

thanks again,

In General questions | Asked By Alexander Sanita | Jun 29 15
1 Answer

Extract current insulation before spray foam in the attic?

I am going to spray foam my attic, underside of roof, and all penetrations with open cell foam to air seal that portion of my conventially built and insulated house. My contractor is telling me I must extract the current fiberglass loose insulation now on the attic floor. While I am willing I can't fully understand the science of needing to extract the current insulation. I am being told there would be two thermal barriers and with AC ducts in the attic the would be a moisture problem.

Anyone have advice or help with the science of this decision.

In Energy efficiency and durability | Asked By David Adams | Jun 26 15
1 Answer

OTR Microwave as range hood in tight house?

I'm looking at a range hood for ventilation in a new, tight, house build. I've read the articles like:


which talk about buying a range hood with a small exhaust fan. Martin recommends 150 CFM to 250 CFM with a tight house.

In Mechanicals | Asked By Nick Hall | Jun 26 15
1 Answer

New house build & painting inquiry

Hey Guys,

Have few questions and need some help.

Here's some detail on the job in question

New build and is in the process of getting the dry wall finished (smoothed out). Inquiring about the interior walls.

Walls in the Basement are 9' high, ground floor at 9' & @ some places 10' and the second floor at 8'

Trim will include approx, 62 windows, 44 doors, the base board and two rooms with crown mold

He will also caulk the outside of the windows

He plans on doing a base coat and two color coats with sanding in between all three coats.

In General questions | Asked By beenash khan | Jun 28 15
6 Answers

I'm building a home in northern Virginia, climate zone 4

I'm building a home in northern Virginia, climate zone 4. Most of the windows are to the open south, and we plan to shade them for solar access in winter and solar screening in summer. However, it's not practical to shade some of the windows.

I plan to use high solar heat gain for the basement (and exposed concrete floor), and low solar heat gain for the second floor that will have enough heat anyway -- and probably some mixture on the first floor with the master bedroom and living areas.

In Energy efficiency and durability | Asked By Esther Streusand | Jun 26 15
5 Answers

Flush-mount exterior electrical boxes in board & batten with rigid foam and rainscreen?

Good evening all,
I'm still working thru issues involving board and batten over strapping and rigid foam. Now I'm looking into the exterior electrical boxes (for outlets and for lights).
I'd like the boxes to be flush-mounted, with the "rain screen" (do we still call it a rain screen if the strapping is horizontal?) space serving as a conduit chase. That would minimize penetrations of the insulation and WRB- while avoiding surface-mounted conduit.

In GBA Pro help | Asked By Ben Rush | Jun 25 15
3 Answers

Do I need to cover XPS in an attic?

I know codes vary from town to town but I'm looking for the general code requirement/interpretation for this. I have used R-10 2" XPS for the interior of basement walls. I know that it must be covered with drywall or another similarly accepted material for compliance and I have done so. I also have learned that the exception is between floor joists at the rim joist and have benefitted from this exception...wouldn't that be a pain of a detail! I now have to build an enclosure that had never been built for a fire box that protrudes into the attic over the garage.

In Building Code Questions | Asked By Tyrone Powell | Jun 22 15
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