Thin Concrete

Ferrocement might work for this.

Strength of concrete is generally determined by it's compressive strength in PSI.

That is somewhat misleading because it fails to take into account the thickness of the slab.

GENERALLY, 2,500 PSI is the lowest strength readily available. But, I believe that 2,500 PSI figure is based on a solid base and at least 3.5 inches of concrete to absorb the load.

How much do your horses weigh? Are the shod? Do some calculations on size of contact area per hoof of your heaviest horse.

My non-scientific guess would be about 2 inches over an existing base of concrete.

Sealing the cracks before beginning the pour is strongly recommended.

I'd talk to a local contractor first.

We had a similar issue in our shop, The floor was constantly damp, and even slick at time.

Because our floor was at close the same level as the outside grade, we wanted to build it up, in case of heavy rains it did not run through the shop.

We just added 3 1/2" of cement, and this also solved it considerably.

This I have to ask, is it what's called Sweating Slab Syndrome

This may have been our problem also, it just that it worked out for us because we had to build the floor up in case of mild flooding due to heavy rains.

Otherwise, I believe one could put a vapor barrier on before you pour.

if you're seeking a Mickey Mouse solution you will find one in the responses. I suggest you tear out the old floor.....you got your monies worth. get your drainage and grading issues straight, pour a new floor and enjoy 50 more years

Many thanks for all your replies - much to think about and to follow up on. What I forgot to mention is that on my neighbours side of one of the stable walls is a concrete slab which abuts our stable wall 300mm above our stable concrete floor, so the wall is damp as the water in the damp earth seeps through the stable wall when there has been rain - many days during the winter. Cutting away the concrete slab from our wall is not an option.

I'm probably only looking for a 5 or 10 year solution. Digging out is an ideal solution but I'm trying to avoid that. Painting something over the floor sounds a good idea but the damp wall will not of course take to a coating. I have thought of laying a DPM under a new floor and running the DPM up the wall and holding that permanently in place with a strip of treated plywood as it is 'only' a stable. The problem comes at the entrance where the horse would have to step up and possibly stumble, to the new higher floor.

Ramp?

A 5 to 10 year solution?

I think kramarat has a good Idea with the spacers, plywood and plastic.

That does seem to give way to ease of installation and you can also put down a "WEAR" layer of 1/2" plywood on top of the 3/4" plywood (with plastic in between) so when the 1/2" plywood is worn out or disgusting, you rip it out and install new 1/2" plywood and the 3/4" plywood is still in good condition. I would suggest a concrete ramp outside the doorway that is level with the new floor.

In my response above I mentioned improving the drainage outside the walls - that's the ideal location, but sub-floor drainage can also be installed on the inside to fix water seepage problems. Now that you provided additional crucial info, I can see where you might need to make the drainage improvement inside.

I'd still recommend talking to a basement/waterproofing company.

If a potential future buyer also has horses, their inspection report might conclude the same work needs to be done before they'd buy.

Do the right thing for this animal. Rip out and pour new.

The conditions you describe can cause hoof problems. You should investigate alternatives to concrete.

If I use the ramp idea there should not be any hoof probs as the horse will be standing on rubber matting. I'll just have to try to keep the ramp outside the door/area where the horse stands.

Here is my suggestion. For the health of your horses and yours also I suggest ripping out the old concrete and installing a drainage system like the one in the picture below. Between the crushed rock and the finished concrete install a 20 mil plastic vapor barrier to help resist moisture seeping into the concrete.

It would help to know where you live so I could factor weather into the equation!

I'm not familiar with the proper care of a horse and it's hooves, so if concrete is not optimal, then what is? For a solid and easily cleanable floor, this is my suggestion.

If you pour over the existing concrete, you will have nothing but problems. Take a little time and do it right, the health of your horse is at stake!

Throw down some 6 mil plastic, throw down some 1" x 1" spacers on top of the plastic, (making sure there are plenty to support the horse and keep the floor from buckling), then screw down some 3/4" exterior grade plywood on top of the spacers.

The horse will also like not standing on concrete all the time.

I'd say to throw the plywood directly over the plastic, but you would have to find a way to join the plywood to keep it from sliding around.

I would just pour hot tar into the crack in the concrete floor.....

Sump pump preferably along the wall neighboring the floor higher then yours. This water will find it's way around the foundation to the sump and also keep the water from under yours under control.

Don't know your relationship with your neighbor. But most building done like this on foundation with floors higher on one side. The out side grading is on a slope. the foundation may be exposed below the neighbors floor and a drain could be installed.

Two inches would be my minimum.

Many thanks for everybody's help. What we are going to do is to render the walls up to 3 feet with a waterproof render, lay a DPM on the existing floor and glue that to the render with double sided tape for the purpose. Then lay 4 inches of concrete over the top. At the doorway we will dig out some of the existing floor so that the new floor level can be sloped down to the existing entrance. QED (I hope!).

Your plan of action looks like you really took heart to a lot of suggestions. You being the one there and able to see all the small issues and also probably have a good friend or contractor assisting you, you and you alone will make the ultimate decision on the work to be performed. A picture of the finished job would be awesome too!

Thank you for the final resolution. It's nice to see a project all the way through and you have also schooled me in what a Horse likes to stand on!

If you are going to do that extensive a project, install a "French drain" system around the inside, not outside, perimeter of the existing floor before adding anything. Install at least one or more cross pipes between the perimeter pieces to drain the center and more. This entails creating a small trench, filling it with several inches of gravel, perforated drain pipes connected to each other, more gravel and finishing the floor off to the existing level (usually concrete). At a corner of the connected drain pipes install a sump and a sump pump. Drain to the outside or a storm drain. This is what is done for basements in high water table areas or with drain problems.

This will remove the existing water immediately below the floor and eliminate future water problems. It will also make your modifications more effective.

Good Luck, Old Salt

I know the guy who poured the roof of the Moscone Center in San Fran. He told me to use Xypex concrete sealer in my basement and pond. I just did the pond with much success. It migrates into the damp concrete and expands in the cracks and seals them up permanently.

Many thanks Deefburger, that sounds fantastic and their videos suggest it could be my solution!! Xypex have a UK office and I'll call them in the morning and let you know what they say.

I'll also follow up on bullardrr's great epoxy suggestions as well.

Forget about concrete top coat. Hydro blast clean, blow dry, then apply a very low modulus epoxy to fill the gaps and cracks, then top coat with the highest modulus epoxy you can get. BASF sells it all. Sika and DeNeef, too.

Or, Hydro blast and rhino line. There are all kinds of spray-on urethanes available for hire.