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8 Answers

Should I install electric tankless hot water, a heat-pump water heater, or solar hot water?

So I'm in the process of specing out and finishing design on a Deep Energy Retrofit/Whole House Remodel on an old 1858 farmhouse.

House Demographics
We are in Zone 6a - NH.
PERSIST Technique is being used throughout.
R20 slab/R20 Sandwich Foundation walls/R40 above grade walls/R60 roof
We will have 9.3 kW of PV solar, and our current plans include two Solar Thermal Panels and and 80gallon Steibel-Eltron Water Heater/Storage Tank for our domestic hot water.....

Asked By brad hardie | Jan 23 15
13 Answers

Double Staggered-Stud Wall vs. 2x3 + Foam Strip + 2x4 Wall

My new house will be in a part of climate zone 2B in Arizona where the winter nights often dip into the 30s and the summer days often rise to 100 with around 45 days of "monsoon season" mostly in August when we'll get an hour of thunderstorms once or twice a week. We have moderate to severe termites.

Asked By Jeff Cooper | Jan 23 15
11 Answers

Longevity of double wall construction?

I'm currently designing a new home as an owner/builder (construction to begin later this year) for the Edmonton, Alberta area. I have several years of building experience, however I have to admit that I've only ever done status quo jobs - 2x6 construction with fiberglass batts, a poly vapor barrier and OSB sheathing.

Asked By Matthew Sokalski | Jan 23 15
0 Answers

Windows - Can Spray Foam vs EXO AIR Foam Tape

I noticed that builders will use canned spray foam to fill in the gaps between the window and the window bucks. The spray foam is messy and needs to be trimmed back on the interior and exterior since trim work cannot be done properly. I also question spray foams ability to expand and contract as window frames do over the course of the life of the home. I also have seen smoke pencil tests done after spray foam and there are noticeable air gaps between the window frame and buck.

Asked By Peter L | Jan 24 15
5 Answers

How to insulate a block house?

i am rebuilding a small block house with a full basement in Northern Ohio. After researching the forum it seems like the consensus is to insulate the outside. My concern is that moisture in the walls from the ground or footings/slab will need to escape to the inside of the house since the rigid insulation XPS will create a vapor barrier on the outside. Any feedback or suggestions will be helpful. Jay

Buildintegral@gmail.com

Asked By jay cooper | Jan 23 15
0 Answers

Whats the best way to integrate rain water to a condo system

Hi,

First of thank you for having such a wonderful forum to share infornation on. I have found this place very usefull in the past.

To my question: im designing a 7 story medium sized condo that will house 6 families. Im thinking of integrating rain harvesting to the building as we some times get droughts and i hate to see all that rain water go to waste. I think it should be regulation to have some sort of backup water sytem just incase the mains dry up. But for now will just be using rain water for the watering closet.

Some numbers:

Asked By Osman Naskali | Jan 24 15
4 Answers

Closed crawlspace ventilation choices

I'm in the process of closing my 900 sqft crawlspace and need to find a way to ventilate the space. One thought I had was to use the old oil furnace chimney/flue as a way to send the air up and out with the help of a small(20cfm) bath fan. The flue is centrally located and close to an existing outlet. Or is it better to seal the flue (or remove it all together) and duct the air through the foundation wall.
Particulars:
zone 4 asheville nc
house built in 1969
neighbor had his crawl space tested for radon and was negative.
13mil barrier sealed to block wall

Asked By terrell whitworth | Jan 23 15
2 Answers

What is the best heat-pump water heater for Zone 6A?

So you guys have more than convinced me to go with a heat pump water heater. I am going to have 9.3+kW on my roof. Should I just buy a heat pump water heater or buy a Marathon type electric water heater and add on a heat pump?

Asked By brad hardie | Jan 23 15
1 Answer

Roxul Comfort Board vs. Thermafiber RainBarrier

Any differences I should be aware of before I choose? I am wanting to use mineral wool for exterior insulation on a wood frame, two-story dwelling. Very impressed with Roxul online information, technical specs etc. Can't find much about RainBarrier, other than the company info sheet, but it's 1/2 the price of the Roxul. Thermafiber says that the Rainbarrier HD is the product they have made to be comparable to Comfort Board, but cannot find any comparisons between the two.

Asked By Caitanya Joy | Jan 23 15
4 Answers

Slab on grade floor repair

About 20 years ago two rooms were added onto this house, both have a slab on grade and the floor tiles are cracking, i had to repair a wall in one of the rooms, and it looks like the floor was the slab with a styrofoam sheet on top (2-3 inches thick), with 1/4in plywood, black adhesive (tar?) and kraft tiles on top (i have no idea what these tiles are called, they are 12x12 in, used in many schools and older buildings, are less then 1/4 in thick and are the same fibrous material all the way through (and i'm hoping not asbestos, they were installed about 10 years ago i am told).

Asked By Alan B | Jan 22 15
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