Do I need to fill this gap between the foundation and the the patio?


Should it be filled with flexible material, such as backing rod and cement caulk?

q do i need to fill this gap between the foundation and the the patio
q do i need to fill this gap between the foundation and the the patio
q do i need to fill this gap between the foundation and the the patio
  12 answers
  • Deb K Deb K 5 days ago

    Hello Hristo, I would say yes you should fill it to reduce the risk of seepage into your home, the caulk should be flexible to allow expanding and contraction, hope this video helps you out

  • Cheryl A Cheryl A 5 days ago

    here is more info for you

    flex seal liquid you can pour it in the gap, brush it on, etc for seal you can find at Home Depot type stores

  • I would fill it, especially if you have a basement underneath, etc. We didn't have a gap filled where our patio door was and it caused some leaking down into our basement. Not a lot, but enough that it needed to be fixed.

  • Hristo Hristo 5 days ago

    It's quite deep, should I fill it in with something first (sand?) before I even put in a backing rod?

  • William William 5 days ago

    Fill it with a backer rod first then use cement caulk. Needs to be flexible.

  • William William 5 days ago

    Yes you can use a self leveling sealant. But it needs to be flexible or it will crack. The patio and foundation move differently.

  • Dee Dee 5 days ago

    I would fill it with sand or top soil first. then put backer rods on top and then seal it with a self leveling sealer.

    • See 3 previous
    • Dee Dee 4 days ago

      Polymeric sand works best to fill gaps between 1/4 inch and 1.5 inches wide. Wider joints will require more time to harden. Some pavers are designed to fit together like puzzle pieces – if the gap is too small, polymeric sand won't help.


  • Kmdreamer Kmdreamer 5 days ago

    No not if you don’t want to .you could cork it or put some mulch in it

  • Betsy Betsy 4 days ago

    Hi Hristo: I would. You don't want water getting into there and freezing and doing who knows what to the underneath area. What I suggest is to get some sand. Not play sand, but this type of sand, which has several names. Sweeping sand, masonry sand, etc. It's the type that will go into cracks and fill them in. Sort of like the stuff in an egg timer. Anyway, fill the crack with this sand (it takes a lot) to about 2" from the top. Then use some foam backer rod, which comes in different diameters to fill the gap to about 1/2 inch from the top and then seal it all with something like Sakrete Crack Filler. All of these things can be obtained from a home improvement store and are not expensive. One thing I found out about the Crack filler when I had cracks in the top of my chimney, was that this stuff is relatively thick, like honey. A guy at the store told me to heat it up and it would pour out easily. Since it was the fall and the furnace was on, I put the container in front of the vent for a cycle. It came out very nicely, sunk into the voids and I haven't had a problem since. Anyway, this is how I fixed the crack between my house and patio.

    Good luck

  • Kathy Gunter Law Kathy Gunter Law 4 days ago

    Mortar or caulk should fix the issue and look good.

  • Mogie Mogie 4 days ago

    Pea gravel would allow for some shifting and drainage at the same time.

  • Annie Annie 2 days ago

    You could put sand behind it, filling the space that way. Then seal with caulking, but be sure the caulk you choose is flexible. Ask at the store, they will sell you the right one. You need flexible because the weather will make things contract and expand. You don't want to end up with cracks!