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6 Answers

Roof insulation for a West Baltimore row house

I've read some earlier GBA discussions about insulating brick buildings and those with flat roofs, and I'm planning to follow the guidelines I've gathered from those. My question is about the full insulation process for the roof when you use spray foam on the interior side of a flat roof. I recognize that the best advice is to put the insulation on the exterior side on top of the sheathing, but for a variety of reasons, that wasn't possible when I had my roof replaced in the fall.

In Energy efficiency and durability | Asked By Timothy Werner | Feb 20 17
9 Answers

Under tile electrical heating - Schluter Ditra Heat system 2017

Clients have asked me to install under tile electric heating. I've hear good things about the Schluter Ditra Heat system, however I've also read two things that worried me when this system was new to the US.

1. The thermostat only allows the heat to warm up to 84 degrees. You might feel this on your feet but it seems unlike to warm or dry the air above, even as a secondary heat source. Other systems allow 104 degrees. Is this still correct?

2. The Ditra heat thermostats produce a very loud clicking sound that is annoying and wake some people up.

In Green products and materials | Asked By Ryan Kennedy | Feb 20 17
6 Answers

Paint OSB subfloor to protect from rain during slow construction?

The house I'm building in central Arizona has a subfloor of 23/32" Norbord Truflor OSB on i-joists over a ventilated crawlspace. I'm building by myself and very slowly, so it might take me three months before I have walls and a roof. In the meantime, I've considered protecting the OSB from weather by painting it with Rust-Oleum Porch and Floor, which is designed to withstand sun and occasional puddles of water. On average, my location will get 6 days/1.2 inches of rain in March, 3 days/0.7 inches in April, and 2.1 days/0.3 inches in May.

In General questions | Asked By Jeff Cooper | Feb 21 17
1 Answer

Insulating attic rafters

I'm looking for some advice on the proper method to insulate attic rafters. We moved to the mid Atlantic a year and a half ago. Our home is a two story colonial with a vented walk up attic. After experiencing the seasons in our new home. We've come to the determination that we need to somehow condition our attic space. Due to the ceiling only being 6'3" the entire length of the house, we realize that the space cannot be livable (lesson learned). It currently has a ridge vent and screened vents on each end of the house. There are no soffit vents. I've priced spray foam -$6000.

In General questions | Asked By lifeguide | Feb 22 17
11 Answers

Need advice on insulating walls

Looking for advice on insulating/treating interior walls in a split level kitchen where half of the wall is in-ground and the other above. Original walls were brick with concrete block, kraft/tar paper on interior side, 3/4" furring strips topped with 3/4" plaster. 2 exterior walls are now stripped from the interior to the concrete surface (was more practical to replace vs. patch drywall after rewiring/replumbing). We found no mildew and the room is comfortable - so one thought is to re-create what we had.

In General questions | Asked By Martin Holladay | Feb 20 17
4 Answers

Whole House Ventilation

I have a 3 bedroom, 2 story cape cod style house (1st floor 1500 sq ft, 2nd floor 500 sq ft; open floor plan) with a full basement (1500 sq ft). It is insulated with icynene except the 3 sides of the basement below grade, which are concrete-filled block lined with styrofoam wallboard (R 7.5) and 1/2" drywall. The house is in a semi-rural location in East TN (Mixed-Humid Zone) at 1000' elevation. Two adults and 4 dogs live in the house. Central heat and air is provided with an electric heat pump.

In General questions | Asked By David Edwards | Feb 21 17
3 Answers

Building a house in Zone 6

Building a house in zone 6. Framing nearly complete. Too cold to roof now with asphalt shingles, but rain protection needed. Roofer asked builder if he should extend the "ice shield" which I understand is vapor impermeable, over the whole roof, or cover with ?

Issue relates to the potential trapping of moisture in the sheathing if two impermeable membranes are used.

In GBA Pro help | Asked By Frank Torti | Feb 21 17
3 Answers

How to prevent or control humidity, mold, etc. in an indoor Retail, Dining, & Entertainment structure with a large body of water


I am a student at the Savannah College of Art and Design and I need some information on proper indoor air quality and I have no idea where to start looking. My project will be based in Cappadocia, Turkey where the air is usually dry and the summer months are in the 70s while winter months are low 20s.

In General questions | Asked By sarahcehm | Feb 21 17
4 Answers

Do pellet stoves generate much creosote?

Having lived in a house with wood heat for over 40 years, I've fairly familiar with the ways in which wood stoves can contribute to creosote formation in chimneys and stovepipes. However, I'm not very familiar with pellet stoves.

A friend recently wondered about creosote formation in a chimney connected to a pellet stove. So I'd like to hear from owners of pellet stoves: Does your stove lead to more or less creosote formation than a typical wood stove?

-- Martin Holladay

In General questions | Asked By Martin Holladay | Feb 17 17
8 Answers

New home build in Iowa (Climate Zone 5)

Is it possible for a new home build in Iowa, climate zone 5, to not have under slab insulation? What's the min code requirement for a poured concrete basement with walkout basement?

Is it normal to also have external foundation just sprayed with waterproof membrane and tiles?


In Building Code Questions | Asked By user-6759891 | Feb 20 17
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