Hot Tub on stamped concrete surface

[Andy0482]

We have a stamped concrete patio and wanted to place our hot tub there. I read other posts where people were concerned with how slippery it can get. In our case the wet concrete doesn’t get very slippery.

Our patio has a natural rock pattern that causes the surface to have indentions and not be completely flat. Does anyone think this will be a problem for a hot tub?

Thanks

[Levelheadsteve]

I think you're fine if the indentations aren't varying greatly, i.e. less than 1/4" or so.  If you can lay down a 2x4 and fit your finger underneath in places, you might have problems. Mine is being placed on stamped concrete as well, but on a smoother section without much variation. I almost bought a Spa Level-R, but ended up not needing to when we decided to place it on the smoother section of our concrete. The owner /builder told me he could have it shipped to me in about a week.  Price is a bit steep though.  About $600.  It also raises the height of your spa several inches.

[trichert]

Andy,

First on the slippery question, its not the fact that its stamped concrete that makes it slippery, it is the sealant.  If yours is not slippery when wet, it is not sealed properly.

Putting a hot tub on top of stamped concrete does not present a problem except for the following two considerations

1) Almost all stamped concrete patios are sloped for runoff.  Even a 3/4 - 1" slope difference over the 7 foot run of the tub is going to cause you issues.
2) The concrete will hold up to the tub fine, but if you ever move the tub, the stamped concrete underneath will be permanently marked and discolored.

[Andy0482]

A rep from the dealer took at look at it and said it shouldn’t be a problem. Levelheadsteve thanks for the 2”x4” idea. I tried one out and I was far from putting my finger under the board.

Trichert the acrylic sealer used on the concrete has additives to help with slipping. When I say it doesn’t get slippery I mean to the point of concern. It is slicker than broom finished concrete for sure.  Also thanks for pointing out the slope issue. I had that concern after the original post. The dealer rep also took a look at that today and said it was all right too.
 
I appreciate the responses.

[trichert]

Sorry i'm going to be stuck on slope for a minute as it is usually an issue

Did they actually measure the slope?  Or did they just glance at it and say "that will be fine".  I would be VERY wary of the latter.  Most tubs have neck jets these days, even if the slope is 'fine' for the structural integrity of the tub if there is 1" fill difference from one side to the other it will cause issues with the neck jets almost 100% of the time.  You really really want completely level and I've never seen a poured concrete patio that was level that wasn't built for that purpose. 

[Levelheadsteve]

Do the neck jets cause problems even if the downward slope side is where the filter and water intakes are?  Or are you saying if the slope causes the neck jets to be above the waterline it is then a problem?

[trichert]

If the jets are below the water line, the water shoots across the tub and out of the tub.  Its an unfun situation. 

[Topline Mike]

I'm not sure why it would be a problem if you could stick your finger under a 2X4?  Picture shows what I did for the hot tub base because my patio was pitched away from the house, and also, the patio would heave up and down with the frost.  You can see in the pic, I don't even have plywood over the joists, there are 1' gaps in between them.  It's been about 10 months since installation, and still holding! 



Finished