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9 Answers

Unvented roof deck with dense-packed cellulose -- vapor barrier?

Hi I just dense packed my attic ceiling (it is a livable space, not crawl) with dense pack cellulose (8"), held in with insulweb. we put the cellulose right up against the roof deck. I am concerned whether I need a vapor barrier and where it should go. My plan was to just put rough cut wood (not tongue and groove ontop of it for the ceiling, but a few people who looked at it thought I might need a vapor or air barrier. The roof is not vented.

In General questions | Asked By carrie da | Jan 29 15
4 Answers

Combining electric cove heaters with PV

In a recent blog, Designing an HVAC System for a Cold Climate, Malcolm Taylor is quoted as recommending electric cove heaters, and a link to the Comfort Cove line from Radiants Systems, Inc. is provided in the blog text. Searching Green Building Advisor turns up half a dozen other references to cove heaters, all very short, and all positive. I wonder if there is more useful advice on choosing and using this technology for supplemental heat.

In Mechanicals | Asked By Derek Roff | Jan 29 15
13 Answers

Does a flexible stainless steel chimney flue really need an insulation wrap?

I am preparing to install a stainless steel flexible liner inside an unlined masonry chimney on an exterior wall to provide draft for a wood stove. Every internet website selling the liners stresses the need for an insulation wrap to keep the vapors warm, improve the draft, and diminish creasote buildup. This has also been emphysized at GBA for similar reasons on multiple occasions. The available wrap liners are typically alkaline earth silicate (AES).

In General questions | Asked By W. Timothy Ward | Jan 26 15
8 Answers

Ductless minisplit retrofit question

I live in southeastern NC, near the coast. My house is just under 1900 sqft with a bonus room over an attached two car garage. My HVAC ducts are in the unconditioned, vented attic. I understand the problems with this. Would a ductless minisplit make sense as a retrofit option? If so, can you just remove the ductwork and patch the drywall where the supply registers are? How do you determine how many head units you need and the best places to install them? I was thinking about this as an option for when I eventually have to replace my heat pump and/or air handler.

In Energy efficiency and durability | Asked By Jason Dennis | Jan 12 15
4 Answers

Waterproofing exterior of basement wall with spray foam

Hi, Recently, I had a problem, my basement wall was bowing in. A company came out and used hydraulic jacks and straightened the wall out. They dug out the exterior and supposedly sprayed a foam on the outside to waterproof. My walls now leak horribly when they did not leak at all prior to their work. They said they could not put a bladder on the exterior because the walls were the old stacked limestone so they used the foam which they said would do the same thing the bladder would.. I called them and now they are saying the foam is not a waterproofer.

In General questions | Asked By Josa Combs | Jan 29 15
2 Answers

Adhesive and ignition barrier for unfaced polyiso?

I got couple pallets of polyiso from an insulation recycler. It is NRG Insulation, 1.5" stuff. But it isn't foil-faced. Will be installing those in my basement with poured concrete walls.

Two questions:

1. What is the best adhesive (I can hopefully get at Home Depot or Amazon) to glue those polyiso panels to the basement wall, and how much of it do I use per panel?

2. Since it is not foil-faced polyiso, can I use FSK paper for an ignition barrier or is there another alternative, besides drywall?

Thanks!

In Green products and materials | Asked By Apollo S | Jan 28 15
10 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?

In Green building techniques | Asked By Alan B | Jan 22 15
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

In Energy efficiency and durability | Asked By terrell whitworth | 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

In General questions | 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.....

In General questions | Asked By brad hardie | Jan 23 15
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