Hi guys... this may help your situation...
Several years ago i was called to a problem with one of our customers that had rising damp through a 150mm concrete slab that formed their garage under a three storey town house.. regulations here in the uk do not call for a damp proof membrane within garages so we had constructed it satisfactory to the regulations. Not content with pushing the customer away i spent a few days investigating what we could do to help the problem.. also i knew the company would not front the cost of ripping the up the floor so my options had to be on the cheap side.
The customer still used his garage for cars and to make matters worse he had to drive in on the angle so any surface treatment would scuff off.
I looked at several manufactures all claiming to solve the problem in one way or another but giving it some thought i came up with the following.
I needed something that would soak into the concrete pores, set, and seal the concrete whilst not leaving a coating on the top. Any surface treatment would brush off or wear off when the car turned.
after spending 6 weeks visiting the floor it had its own behaviour damp issues. about a day after heavy rain moisture would soak up through the floor and darken the concrete , three days without rain leaving the front garage door & single rear door open for ventilation the moisture had disapeared and the concrete looked dry. This was a reoccuring pattern.. put down humidity, air pressure & capilary action....
We purchased some basic water repealant silicon that is normally sprayed onto surface brickwork and sprayed it onto the surface with a cheap hand pressure sprayer.
the concrete was dry when we applied the coats and teh first coat was sucked into the concrete, a second coat was applied the next day, the concrete darkened to a wet look colour and remained so. tow days later we returned, where some pooling of the sealer had remained ontop a very thin crust was formed which was brushed off..
http://www.edirectory.co.uk/pf/880/...+one+coat+water+seal+ultra+25ltr/pid/31838401
The floor looked uniform in coulour though this ws now slightly darker than wet concrete. A test of cup of water was thrown over the floor and it just sat on the surface not sinking in. Our thoughts were as the top 1" or so of concrete was now effectively sealed water could not be drawn up through by cappilary action and leave via the surface. Two days later we applied two coats of garage floor paint (solvent based onto the concrete)did it work? well we checked 1 year later and the chap was delighted.. problem was solved... floor paint was unworn and the moisture problem dissapeard overnight. I called in to see him today (4 years on)but he has moved last year, the new owners have reported no problems what so ever.. the floor paint was showing slight thinning where the turning was.
In my opinion it worked a treat & cost no more than £100 + labour about 1 day... I not saying it would work in your situation and certainly I would imagine you have to get the floor dry for the material to soak in... but in this situation it worked brilliant.
Either way hope this helps in some way
Good luck
Andy
