Moisture-proofing crawlspaces
 

Anyone here with experience making a crawlspace moisture-resistant (with
plastic membranes or other means)?

Please read the question carefully before answering. Not looking for
speculation or even helpful links to things I can find myself on the
web. Looking for personal experience. (Funny anecdotes accepted as well.)

Reason for the question is a client with a damp crawlspace, dirt floor,
and an overly-humid house. (Older house, vents installed, but no
circulator, dehumidifier, etc.)


--
Washing one's hands of the conflict between the powerful and the
powerless means to side with the powerful, not to be neutral.

- Paulo Freire

Moisture-proofing crawlspaces
 

"David Nebenzahl" wrote

Anyone here with experience making a crawlspace moisture-resistant (with
plastic membranes or other means)?

Please read the question carefully before answering. Not looking for
speculation or even helpful links to things I can find myself on the web.
Looking for personal experience. (Funny anecdotes accepted as well.)

Only a funny 'what not to do'. Mom was about to buy a house (we flipped
houses for a living but it didnt have that name back in the 60's/70's). To
attempt to seal this particular house, they'd tried to lay down plywood on
the dirt then paint the heck out of it with water proofing paint.

Yup, you got it. Wet rotted termite heaven. We didnt even bother to look
closer, just noted a huge termite infestation obvious to the eyes and walked
off laughing.

Moisture-proofing crawlspaces
 

On Jan 8, 1:53*am, David Nebenzahl wrote:
Anyone here with experience making a crawlspace moisture-resistant (with
plastic membranes or other means)?

Please read the question carefully before answering. Not looking for
speculation or even helpful links to things I can find myself on the
web. Looking for personal experience. (Funny anecdotes accepted as well.)

Reason for the question is a client with a damp crawlspace, dirt floor,
and an overly-humid house. (Older house, vents installed, but no
circulator, dehumidifier, etc.)

--
* Washing one's hands of the conflict between the powerful and the
powerless means to side with the powerful, not to be neutral.

- Paulo Freire

I covered the ground with 10' wide strips of heavy plastic sheeting,
each side overlapped about 10" and taped with tape designed for
plastic sheeting. Around the perimeter, I staked it down 16d nails
run thru a plactic cap from roofing caps. I have found no signs of
moisture in my crawl space. However I did get a few holes in it where
mice got under it and chewed their way out. A few handfuls of Decon
thrown under there once a year stopped that problem.

Red

Moisture-proofing crawlspaces
 

On 1/8/2009 10:10 AM Red spake thus:

On Jan 8, 1:53 am, David Nebenzahl wrote:

Anyone here with experience making a crawlspace moisture-resistant
(with plastic membranes or other means)?

Please read the question carefully before answering. Not looking
for speculation or even helpful links to things I can find myself
on the web. Looking for personal experience. (Funny anecdotes
accepted as well.)

Reason for the question is a client with a damp crawlspace, dirt
floor, and an overly-humid house. (Older house, vents installed,
but no circulator, dehumidifier, etc.)

I covered the ground with 10' wide strips of heavy plastic sheeting,
each side overlapped about 10" and taped with tape designed for
plastic sheeting. Around the perimeter, I staked it down 16d nails
run thru a plactic cap from roofing caps. I have found no signs of
moisture in my crawl space. However I did get a few holes in it where
mice got under it and chewed their way out. A few handfuls of Decon
thrown under there once a year stopped that problem.

Thanks. That's close to what I was thinking of doing.

Now for the next part: client would like to be able to walk on the dirt
(uses crawlspace, which is nearly basement height, to store stuff in).
How about throwing down a few sheets, say cheap OSB, over the plastic?
Would that be stupid and attract termites? The idea is to protect the
plastic membrane from being perforated.


--
Washing one's hands of the conflict between the powerful and the
powerless means to side with the powerful, not to be neutral.

- Paulo Freire

Moisture-proofing crawlspaces
 

On 1/8/2009 10:10 AM Red spake thus:

On Jan 8, 1:53 am, David Nebenzahl wrote:

Anyone here with experience making a crawlspace moisture-resistant
(with plastic membranes or other means)?

Please read the question carefully before answering. Not looking
for speculation or even helpful links to things I can find myself
on the web. Looking for personal experience. (Funny anecdotes
accepted as well.)

Reason for the question is a client with a damp crawlspace, dirt
floor, and an overly-humid house. (Older house, vents installed,
but no circulator, dehumidifier, etc.)

I covered the ground with 10' wide strips of heavy plastic
sheeting, each side overlapped about 10" and taped with tape
designed for plastic sheeting. Around the perimeter, I staked it
down 16d nails run thru a plactic cap from roofing caps. I have
found no signs of moisture in my crawl space. However I did get a
few holes in it where mice got under it and chewed their way out. A
few handfuls of Decon thrown under there once a year stopped that
problem.

Thanks. That's close to what I was thinking of doing.

Now for the next part: client would like to be able to walk on the
dirt (uses crawlspace, which is nearly basement height, to store
stuff in). How about throwing down a few sheets, say cheap OSB, over
the plastic? Would that be stupid and attract termites? The idea is
to protect the plastic membrane from being perforated.

I think I'd instead be more inclined to throw down some pieces of
concrete backer board or stepping stones. I doubt termites would like
those.

Neither your nor my suggestions are really good solutions. The right
thing to do is to pour some concrete.

--
Steve Bell
New Life Home Improvement
Arlington, TX USA

Moisture-proofing crawlspaces
 

On Jan 8, 12:59*pm, David Nebenzahl wrote:
On 1/8/2009 10:10 AM Red spake thus:







On Jan 8, 1:53 am, David Nebenzahl wrote:

Anyone here with experience making a crawlspace moisture-resistant
(with plastic membranes or other means)?

Please read the question carefully before answering. Not looking
for speculation or even helpful links to things I can find myself
on the web. Looking for personal experience. (Funny anecdotes
accepted as well.)

Reason for the question is a client with a damp crawlspace, dirt
floor, and an overly-humid house. (Older house, vents installed,
but no circulator, dehumidifier, etc.)

I covered the ground with 10' wide strips of heavy plastic sheeting,
each side overlapped about 10" and taped with tape designed for
plastic sheeting. Around the perimeter, I staked it down 16d nails
run thru a plactic cap from roofing caps. I have found no signs of
moisture in my crawl space. However I did get a few holes in it where
mice got under it and chewed their way out. A few handfuls of Decon
thrown under there once a year stopped that problem.

Thanks. That's close to what I was thinking of doing.

Now for the next part: client would like to be able to walk on the dirt
(uses crawlspace, which is nearly basement height, to store stuff in).
How about throwing down a few sheets, say cheap OSB, over the plastic?
Would that be stupid and attract termites? The idea is to protect the
plastic membrane from being perforated.

--
* Washing one's hands of the conflict between the powerful and the
powerless means to side with the powerful, not to be neutral.

- Paulo Freire- Hide quoted text -

- Show quoted text -

With a "crawlspace" that tall, how do you know the moisture is coming
from the ground and not through the walls? (I'm assuming it's dug out
and not multi-feet above the surface). I would not use OSB because of
potential termite problems. I would either pour concrete or use PT
plywood.

Red

Moisture-proofing crawlspaces
 

David Nebenzahl wrote:
On 1/8/2009 10:10 AM Red spake thus:

On Jan 8, 1:53 am, David Nebenzahl wrote:

Anyone here with experience making a crawlspace moisture-resistant
(with plastic membranes or other means)?

Please read the question carefully before answering. Not looking
for speculation or even helpful links to things I can find myself
on the web. Looking for personal experience. (Funny anecdotes
accepted as well.)

Reason for the question is a client with a damp crawlspace, dirt
floor, and an overly-humid house. (Older house, vents installed,
but no circulator, dehumidifier, etc.)

I covered the ground with 10' wide strips of heavy plastic sheeting,
each side overlapped about 10" and taped with tape designed for
plastic sheeting. Around the perimeter, I staked it down 16d nails run
thru a plactic cap from roofing caps. I have found no signs of
moisture in my crawl space. However I did get a few holes in it where
mice got under it and chewed their way out. A few handfuls of Decon
thrown under there once a year stopped that problem.

Thanks. That's close to what I was thinking of doing.

Now for the next part: client would like to be able to walk on the dirt
(uses crawlspace, which is nearly basement height, to store stuff in).
How about throwing down a few sheets, say cheap OSB, over the plastic?
Would that be stupid and attract termites? The idea is to protect the
plastic membrane from being perforated.


Drain-through plastic matting, like they sell to use on loading docks
and commercial kitchen floors, would be a better bet. Or even plastic
48" pallets, if you can find a cheap local source for used ones. If it
is that tall, why not dig out part, and pour a slab? Aside from the
insect bait/rotting factor, you don't want a second vapor barrier, or
anything that could trap and hold grit against the plastic.

--
aem sends...

Moisture-proofing crawlspaces
 

"David Nebenzahl" wrote

Now for the next part: client would like to be able to walk on the dirt
(uses crawlspace, which is nearly basement height, to store stuff in). How
about throwing down a few sheets, say cheap OSB, over the plastic? Would
that be stupid and attract termites? The idea is to protect the plastic
membrane from being perforated.

Best bet there? You know that green 'grassish' outdoor carpet stuff? You
can get remnants pretty cheap. I'd use that. Wont trap moisture in.

This assumes pouring a base isnt in the plans.

Moisture-proofing crawlspaces
 

I had a damp crawl space. Plastic sheeting and a fan solved the
problem.
Lay plastic sheeting on the ground. Overlap as necessary. A small
hole here and there when crawling or putting things on it is not a
problem.
My crawl space was in the shape of an L, with the small end not having
a vent. After the sheeting was laid down, the humidity was still too
high. They make vent-shaped fans that automatically turn on and off
with the humidity. That solved the problem.