Asked on Mar 14, 2012

I have a screened in porch and the floor is cement but it sweats when it rains what can I do to stop the floor from swea

Carol G
by Carol G
  17 answers
  • KMS Woodworks KMS Woodworks on Mar 14, 2012
    The sweating is "condensation" the cold slab reacting with the high humidity of the rainy day. This is just like the sides of a glass of iced tea. you can either remove the humidity....hard with a screened space. Or warm the slab / insulate it which is also hard. Being a screened porch this structure should be somewhat water resistant by its design...so having a wet floor should not be much of an issue. Is there a reason you want this place to be 100% dry?
  • Carol G Carol G on Mar 14, 2012
    yes because I want to make a nice seating area with it and when it is wet it is slippery...is there anything I can put on the cement to stop the sweat? like a sealer or something? I wanted to put tile down on it
    • Canadianlady Canadianlady on Dec 12, 2016

      We use garage flooring, which comes in rolls and is mega easy to install. It's not very expensive, either. It's also waterproof. In the Summer months, we have to use a dehumidifier to suck the moisture out of the air.

  • Carol G Carol G on Mar 14, 2012
    Thank you for the suggestions but this doesn't answer my question because it does not tell me if there is a solution.
    • See 2 previous
    • Rock Griffis Rock Griffis on May 15, 2019

      My front porch does the same thing, and I am thinking of building a wooden rise with the ability to drain or dry underneath it to avoid it being so slippery. What did. you ever do for your issue?


  • Peace Painting Co., Inc. Peace Painting Co., Inc. on Mar 14, 2012
    I believe the issue is the natural temperature differential plus humidity, no matter what is on the floor. My stained garage floor occasionally does the same. Heard of Astroturf? CP
  • Carol G Carol G on Mar 14, 2012
    only that part does it the laundry room is an extension of the same floor but only half of the laundry room sweats..this floor was and addition..I think they did not put visquine. but the point is is there any thing I can use to stop it..like a sealer? that is what I want to know...I know the cause...always did.
  • Carol G Carol G on Mar 14, 2012
    tried astroturf that is what was on it when I bought the house and it smelled mildew so removed it
  • Peace Painting Co., Inc. Peace Painting Co., Inc. on Mar 15, 2012
    Carol, sorry I can't be of much help, that's a tough one on me. It may have to do with the visquine, I don't know. Chas.
  • KMS Woodworks KMS Woodworks on Mar 15, 2012
    The problem is a combo of the air working with the cool slab...in order for this to not occur one of those variables will need to be removed. The humid air could be removed by sealing in the room with glass or solid walls. The slab could be made warmer via a electric radiant heating element set under tile. The fact the the slab is not insulated below would have this "heating" be less than ideal in terms of efficiency. If you want a lower cost alternative to the slippery. A textured paint 'anti-skid" finish can be applied. The concrete will still cause some condensation to form but at least the "traction"will still be there. A built up "insulated floor" is another option, but this would require some engineering to keep horizontal rain from compromising the new surface. A wooden "deck" could be installed over the concrete on thin PT sleepers. This would have the condensation still form on the concrete but the wooden surface above would still be dry and usable. The decking would be "weather proof". This decking could be real wood or one of the many synthetics.
  • Charlotte Smith Charlotte Smith on Feb 19, 2014
    I recently added a screened in patio and it sweats most of the time. Is this normaI? I do live in the Houston area where humidity is always high. What can I do to prevent this sweating?
  • Jody Forslund Wicker Jody Forslund Wicker on May 28, 2017

    I installed some industrial fans from Home Depot couple weeks ago this is the most brilliant thing, I have not had any floor sweating since !! The fans are designed with a wall mount with four-speed's, on the rainy days I keep them in high. Hampton Bay Industrial 60 in. White Energy Star Ceiling Fan

    $56.98 / each


    (237)

  • Kym Langford Ball Kym Langford Ball on Jan 22, 2018

    I have the same problem. I have ceramic tile over a cement slab in a screened-in sunroom. I have an exorbitant amount moisture / water sitting on top of my tile. I would take my Hoover FloorMate out pretty much once a day and soak the water up so that my dogs did not track it inside.


    I finally got tired of it. So I chipped all the porcelain tile up which was nice is it had a skid resistant anti-slip on it. I installed in Italian type tile it was kind of like a slate. It's a little more difficult to clean however since I have put this down in the past two years I have not had the sweating tile over the cement slab in Florida like I did with the ceramic tile


    This post is old so I'm not sure if it will work for you now but I did find more of a slate or an Italian type of a tile worked much better than a ceramic or porcelain and sweating

    • Shawn Shawn on Jan 11, 2020

      Do you know the name, kind, brand of the Italian tile?

  • Gilmer Gal Gilmer Gal on Feb 17, 2018

    The sweating on my East Texas ceramic floored, screened porch makes me want to cry every time it happens! Something the sellers didn't mention :(. Anyway, I was thinking of putting some wood-type flooring down, maybe strip some underlayment into 8" wide strips, (first seal with Red Guard over the tile that is there). The wood on the porch never sweats, so I'm going to lay down a few strips of wood and wait for the next humid day to see if it helps. Seems to happen when the weather changes from cold nights to drizzly days. Nightmare. I keep the litter box out there and my cat has wet feet and tracks it inside. On my wood floors!

    • See 3 previous
    • Gilmer Gal Gilmer Gal on Jan 25, 2021

      That would make sense, but most of the wood is sealed with paint. What isn't sealed seems to stay dry. I think it's almost like a glass of iced tea on a hot, humid day. The condensation is extreme! We still haven't figured out a way to take care of the problem. But I know that the floor is cold when it happens, then it gets humid and sweats.


  • Odile Landry Odile Landry on Mar 04, 2018

    I have a patio with all windows and my patio sweats just like my carport does , what can I do it’s driving me crazy ?

  • James James on Feb 25, 2020

    I was just wondering if anyone has tried a fan underneath porch, which could not only blow some moisture from underneath house and more importantly cause the porch floor to be closer to same temperature as air and reduce condensation.

  • Roger Williams Roger Williams on Mar 19, 2020

    I have the same problem with a covered concrete porch each time it rains. My porch is soaking wet, almost like it rained on the porch with no covering at all. It does this whether there is any wind or not, so it has to be something in the concrete causing it. I have not found a solution either.

  • Jo Ann Walker Hudson Jo Ann Walker Hudson on Dec 03, 2020

    My screened in porch stays wet a lot! Furniture and everything. It has tile floor and like everyone says with the humidity it is wet. It is not at all a pleasing spot to enjoy. Thought about just tearing the whole thing down except the roof part. I may try a fan first. I fear windows would be too costly.

  • Jeryl Jeryl on Nov 28, 2022

    I have the same problem, I have indian limestone on a cement slab floor raised 30" off the ground, screened porch 3 sides on a lake. When the temperature warms up after being cold there is a lot of water on the floor and it is slippery. I am told this is condensation. My neighbors have tabby floors and do not have this issue at all. The tabby surface is more texturized. I am wondering if I just need to pull up this floor and change the material