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6 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

5 Answers

Flooring questions

Hi guys,
I just did the flooring in the basement, and on a different forum in the midst off a question got told off for the flooring I did.

I did concrete slab, 6 mil poly, 1 inch XPS, 1/2 inch OSB.

I was planning to put floor finishings on top. However I was told that it needs to be redone or else the wood will rot.

Does what I did look that bad? Is there a way out of it short of a re-do?

Thanks

Asked By sr kod | Jan 27 15

2 Answers

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

6 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

9 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

9 Answers

Got cellulose insulation, how to fix the interior holes?

They drilled two holes and loose filled it (i know, it should be dense packed). The holes are 2 inches wide, and plugged with styrofoam discs about 1in thick. Some are reasonably tight, some are loose. What is a good way to fix this, if i drywall compound and paint many of these will move over time. I was thinking of using a few cans of spray foam, cutting flush with a painting razor and painting. Would this work well, or do i need to sand and plaster before painting or is there a better way?

Asked By Alan B | Jan 22 15

0 Answers

The GBA web site will be down for maintenance

Beginning at 6:00 p.m. tonight (Tuesday January 27, 2015), the GBA web site will be down for maintenance. For about 24 hours, the site will go into “read only” mode -- meaning that readers will be able to visit every page on our site, but will be unable to post any new comments.

For more information on this scheduled maintenance, see the GBA announcement.

On Wednesday evening, we hope to have the GBA site up and running again -- better than ever. Thanks for your patience as we make these improvements.

Asked By Martin Holladay | Jan 27 15

8 Answers

WRB - Ice & Water Shield or Grace enV spray-on (to breathe or not to breathe)?

Zone-6A building a PERSIST type home with 8" of Neopor on the exterior. Should I wrap the sheathing in Grace Ice & Water or use a spray on WRB like Grace enV. The Ice & water doesn't breathe, and the enV does. No vapor barrier on the inside and currently there are no plans to insulate in the stud cavities.

Asked By brad hardie | Jan 26 15

1 Answer

Insulation

Hi. I am trying to renovate a 65 year old house. It is a 2 story house. The second story has a 4 foot vertical wall and then it turns into the roof. The slope is about a 10/12 slope. What I would like to know is whether or not I should treat the slope as a wall or as a roof for insulation purposes? If it is to be treated as a roof would I have to leave space for airflow? Right now I have diagonal cross bracing between the rafters. If I need air flow I would either have to remove these braces or drill holes through them.

Asked By Floyd Hillier | Jan 26 15

11 Answers

LPG infloor heat with HWH with a heat exchanger in the HWH is too expensive to run!

I have the above home on a monolithic slab. ...LPG to run the HWH and a heat exchanger pipe running through the HWH to heat my floor...TOO DANG EXPENSIVE TO HEAT MY HOME THAT WAY! Suggestions on how to make it more efficient would be appreciated. A air to water heat pump? A heat pump water heater with a heat exchanger pipe running through the HWH? A solar system of some sort?

Asked By Ed Jones | Jan 25 15

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