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2 Answers

Drainage mat below basement slab, to replace stone

I tore out my damp musty basement floor, and we have excavated down 16" to gain some head room, and install 4" foam, below the new slab. I would typically use 4" of gravel as the base, but am trying to find information about the use of drainage mat, or soil gas mats instead (to save labor and head room).

Asked By matt berges | Nov 24 10
2 Answers

Can cellulose insulation in an attic be re-fluffed?

I am installing new light fixtures in the ceiling of a house with cellulose in the attic. As I move around up there, the insulation is being compressed. I assume that this will lessen its effectiveness. What can I do or have done to regain the value of the insulation?

Asked By Vern Tator | Jan 13 11
17 Answers

Crawlspace sealing and insulation

I have read through several of the threads here and while bits and pieces do apply to what I want to know, there were some things unaddressed that I wanted to cover here.

Asked By dennis brown | Dec 22 10
4 Answers

Does anyone have experience with ChemLink caulk or Sealant (NovaLink, DuraSil, etc)

I am trying take the least toxic route while caulking throughout my home.

Given that, the following ChemLink recommendaitons were made
NovaLink
DuraSil
Trim Caulk

Has anyone had any experience with these products? How do they hold up (shrinkage, mold, mildew, etc)? How have they held up over time? Would you recommend them?

I will need to caulk the following areas:

1. The change of plane between a porcelain tile floor and porcelain tile baseboard. I will adhere the Porcelain tile baseboard to an previously painted wall with thinset.

Asked By Georgianna Marquez | Dec 3 10
10 Answers

Need some help with wall envelope design for 110 year old masonry building

I am working on a project which is rehabbing a circa 1890 masonry factory building into apartment units. The existing building is 3 to 4-wyth thick brick masonry walls and that's how it's been since 1894. We are looking at three options:

1 2x4 wood studs held 3/4 inches off the masonry wall, drywall and batt infill. Our least favorite option bc/of obvious issues with gaps in insulation and convective loop currents and more.

Asked By Sara Sweeney | Dec 3 10
6 Answers

Is 3" thickness really enough for a basement slab?

Hallelujah! 1" XPS board is down, so is the StegoWrap vapor barrier, the rebar and soon the 6"x6" wire mesh. So the new basement slab in the old wet basement will be poured on Monday. It already smells better!! (Might have something to do with discovering and fixing the broken sewer pipe just outside the foundation, that was draining back into the gravel basement floor - yuck!!). Today I reviewed the diagram on "How to Finish Exterior Foundation Insulation" and it shows a slab thickness of 3".

Asked By Anita Brosius-Scott | Nov 19 10
13 Answers

How problematic is XPS foam board applied against asphalt-based foundation coating, on exterior?

As we move forward with energy retrofit insulation work on our house, we finally decided, due to our moist clay soils and northern climate (Maine), to insulate the exterior of our foundation rather than the inside walls in the basement. Some fun.
At this point the plan is to keep the interior of the concrete wall exposed to the inside air.
We're laying 2" XPS foam boards against the foundation walls (Obviously that means we'll have to deal with a protective covering above grade).

Today's question has to do with foundation coating on the walls, vs. the XPS foam boards laid against it.

Asked By Anita Brosius-Scott | Nov 8 10
18 Answers

Retrofit addition of footing at foundation base; capillary break?

We're finally addressing our wet gravel-floored utilities basement - we're putting in a slab floor. In digging down around the inside of the foundation wall to lower the floor and make room for the slab etc., we discovered that there is no footing under the formed concrete foundation wall! (This wood-frame house was built in 1936, has 2 stories above the basement, and is in Maine, zone 4-5). Argh. The wall sits on hard dense clay. And guess what? Water trickles in underneath. Contractor suggests forming a footing to the inside of the existing wall.

Asked By Anita Brosius-Scott | Oct 25 10
6 Answers

to add or not to add, that is the question

I am finally getting around to making the attached garage of my house into a den. I knew it was 2x4 framing and assumed it was uninsulated. It had been my intention to remove the existing drywall and add 2" rippers to the studs and fill it with R-19 batts (properly installed). Imagine my surprise to to find R-19 batts already in the 2x4 cavity and properly installed to boot! With the paper stapled to the face of the studs! The question is whether consensus would say it is most cost effective to leave it alone or whether I should stick to my original plan and firr out the studs.

Asked By kim shanahan | Oct 25 10
3 Answers

Laying drain tile in stone trench under slab- @bottom or center?

In preparing to lay perforated drain tile (4" Schedule 20 perforated pipe) in their trenches under a basement slab, there is a difference of opinion between my contractor and the illustrations in Building Science Corporation "Basement Insulation Systems" research report (2006). My contractor suggests that the filter fabric lay directly on the clay substrate, the pipe directly on top of that, and the 3/4" stone on either side of and above the pipe. Then we'd wrap the fabric 360 degrees around.

Asked By Anita Brosius-Scott | Oct 25 10
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