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12 Answers

Thermal energy storage

~3900 square foot house.

I am thinking of building a water based TES tank using ICF in a crawl space.

The plan would be to use RV antifreeze in an active (pump) circulating heat exchanger that sits at the bottom of a tank of water. Domestic water supply would pass through another heat exchanger that sits at the top (for stratified water column effects) inside this tank and preheat water for radiant hydronic boiler and domestic hot water.

I was thinking 12'x12' @ 6' tall for a 864 cubic foot / 6463 gallon tank.

Asked By Jim Pancanke | Oct 21 14
6 Answers

Window U-value comparison to wall R-value and window replacement

We have an 1870s Victorian farmhouse that doesn't have insulation in the walls, and to keep it simple, we cannot add insulation in the walls without going to great expense, more than we can afford.

Asked By Keith Miller | Oct 20 14
0 Answers

Sealing meeting point of brick wall and asphalt driveway

Hi,

My house, a semi-detached, has an asphalt mutual drive between it and the neighbors house to the south that comes right up to the side of the house.

I'm concerned about the meeting point between the asphalt and the brick as it looks like water can collect there and seep into the brick (I have some Interior spalling and suspect that this is the source), but I'm not sure how to address this.

Do I use caulk.. or something with the consistency of tar.. or something like mortar for bricks..?

Some photos here:

Asked By Jon Haque | Oct 22 14
2 Answers

Insulation in old home repair

Hello, I own a 1931 home. I had a window leak it damaged the plaster on an interior wall, roughly a 2'x5' section. Behind the plaster and lath was a later of loose insulation and behind that bound newspaper. Much of the newspaper was rotted, as was a section of the wood behind it. The wood backed the exterior stucco. I removed the newspaper and wood. I am unable to replace the wood that backed the stucco.Instead and added 1" rigid foam.

Here's my question: What do I use next to insulate before I put on the sheetrock, faced or unfaced fiberglass...or something else? I live in Minneapolis.

Asked By Tom Ives | Oct 21 14
4 Answers

Insulation dew points and archaic insulation

I have a couple of questions, both somewhat academic since there may be little to do about them.

I live in a 1938 1.5 story (Cape-style) house in St. Paul, zone 6. About 3 years ago the shoddily-added back porch was falling apart and the roof shingles were shot , so I tackled both in one, replacing the back of the house with a new addition, and re-roofing the entire house using this "cold roof" article in JLC as a model (in short, adds 3" XPS foam plus 1-1/2" air gap above the original roof): http://www.jlconline.com/rooftop-accessories/retrofitting-an-insulated-c...

Asked By Graham Allan | Oct 20 14
2 Answers

Double wythe CMU vs. Thermomass

After living in Europe for several years I have become a fan of concrete. I build in the Southeast and have mainly used concrete commercially and as stem/foundation/retaining walls and for slabs in residential.

Asked By leo kloop | Oct 22 14
4 Answers

PERSIST vs REMOTE vs SIP ?

We are building a new house in MN (6b), considering various wall systems, and trying to get a handle on the pros and cons of each. Thus far we have:

SIP Pros
- Better known construction method, easier to find carpenters, ...
- Well documented construction details

PERSIST Pros
- Seems like it would be easier construction than SIP.
- Easier to get all details correct.
- Provides significant interior space in attic for ducting, extra room, storage areas, etc.
- Chemical elements (foam, osb, etc) on outside of air/vapor barrier

REMOTE Pros

Asked By Walker Angell | Oct 21 14
11 Answers

Curbless shower with a PVC liner -- how to terminate the liner at the floor?

I'm installing a curbless shower----Concrete slab-on-grade with a sump for shower.
Using traditional method for shower floor---PVC liner, with pre-slope and top slope mud beds.
2x2 tile on shower floor and 18x18 travertine on bathroom floor.

My question is how to handle the waterproofing interface between my sump and the bathroom floor level (like where the curb would have been).

Asked By john walls | Oct 19 14
9 Answers

“Air-sealed” can light retrofit vs. Tenmat cover in attic?

I’m planning some air sealing work in my attic. I’ve got a bunch of recessed can lights to deal with, and I had been planning to use Tenmat rock wool light covers on the attic side. This would involve caulking (say, Tremco acoustical sealant) or foaming to seal the Tenmat cover, plus taping up any cuts to allow for electrical wires, etc. After first going into attic, pulling back existing insulation, sweeping the area clean, etc.

Asked By andrew c | Jun 22 14
2 Answers

Mold in crawlspace

I live in Gadsden Al,and we purchased a home and for a couple years its been smelling old,i went under the house and found the mold on the west wall where the flower planter is outside the house and by the pipes coming from the bathroom. I fogged the crawlspace very well with corcodium and I no I have to clean the walls too. But I need to bring the height of my front yard up 1 ft and at a slant to stop the water from ever going back under the house.the flower planter is 11/2 ft high and 12ft long 11/2 ft wide. and has brick on the outside.

Asked By weldon jones | Oct 21 14
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