My back porch floor has a odd problem. It looks like a chemical
reaction. In spots the concrete looks like it is dissolving and
turning to a fine powder. I took pictures of it just a few weeks after
a thorough cleaning with soap and water.

The porch was painted before I bought the house 2 years ago. The paint
is peeling pretty badly. Before it was painted it was covered with
indoor/outdoor carpet.

Also there used to be a hot tub out there. I was wondering if
chemicals from the spa might have caused this.

I made a web page with the pictures:

http://www.clampett.com/FoamingConcrete.html

I would certainly appreciate any advise

thanks

Mort

"Mort Guffman" wrote in message
...
My back porch floor has a odd problem. It looks like a chemical
reaction. In spots the concrete looks like it is dissolving and
turning to a fine powder. I took pictures of it just a few weeks after
a thorough cleaning with soap and water.

The porch was painted before I bought the house 2 years ago. The paint
is peeling pretty badly. Before it was painted it was covered with
indoor/outdoor carpet.

Also there used to be a hot tub out there. I was wondering if
chemicals from the spa might have caused this.

I made a web page with the pictures:

http://www.clampett.com/FoamingConcrete.html

I would certainly appreciate any advise

thanks

Mort

This is Turtle.

It looks like when they poured the slab the curing was not right or the concrete
mix was not good on the slab. I know of nothing that a normal person would use
over a slab that would break it down except a jack hammer or a stick of
dynomite. It may crack but not just powder up.

I think what people who pour concrete would say as a Bad pour.

TURTLE

Mort Guffman wrote:

My back porch floor has a odd problem. It looks like a chemical
reaction. In spots the concrete looks like it is dissolving and
turning to a fine powder. I took pictures of it just a few weeks after
a thorough cleaning with soap and water.

The porch was painted before I bought the house 2 years ago. The paint
is peeling pretty badly. Before it was painted it was covered with
indoor/outdoor carpet.

Also there used to be a hot tub out there. I was wondering if
chemicals from the spa might have caused this.

I made a web page with the pictures:

http://www.clampett.com/FoamingConcrete.html

I would certainly appreciate any advise

thanks

Mort

---------

Hi Mort

No your patio isn't dissolving. What you are seeing is mineral salt
crystals coming up with water thru the cement. The water evaporates away
and the crystals are left behind. There is probably no vapor barrier
under your cement.

When the crystals form they can produce 2000 pounds of pressure, thus
poping off nearly all coatings.

There are one or two products that will seal the concrete below the
surface. They MIGHT reduce or stop the problem. A waterbased epoxy as a
next step MIGHT then work as it will soak slightly below the surface and
form a very strong bond.

hope this helps

paul oman
progressive epoxy polymers
www.epoxyproducts.com


--


"Living on Earth is expensive, but it does include
a free trip around the Sun every year."


============================================
PAUL OMAN Progressive Epoxy Polymers, Inc.
Frog Pond Hollow - 48 Wildwood Dr
Pittsfield NH 03263
10-4 Monday-Thur EST 603-435-7199
VISA/MC/Discover/Paypal

http://www.epoxyproducts.com
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============================================

In article , Mort Guffman wrote:

http://www.clampett.com/FoamingConcrete.html
I would certainly appreciate any advise

This looks like efflorescence. Water is coming up through the concrete
and carrying soluble salts with it. The water evaporates and leaves the
foamy looking powder. There are cleaners that will remove it, but you
really need to get rid of the water problem before the concrete is
destroyed.

--
"De inimico non loquaris sed cogites."

Thanks everyone for the good advice. The yard back by the porch is
always wet/damp so there is definitly a moisture problem. The plants
like it...

mort



On Sun, 23 Jan 2005 06:32:48 GMT, Mort Guffman
wrote:

My back porch floor has a odd problem. It looks like a chemical
reaction. In spots the concrete looks like it is dissolving and
turning to a fine powder. I took pictures of it just a few weeks after
a thorough cleaning with soap and water.

The porch was painted before I bought the house 2 years ago. The paint
is peeling pretty badly. Before it was painted it was covered with
indoor/outdoor carpet.

Also there used to be a hot tub out there. I was wondering if
chemicals from the spa might have caused this.

I made a web page with the pictures:

http://www.clampett.com/FoamingConcrete.html

I would certainly appreciate any advise

thanks

Mort