On Jul 20, 5:39 pm, Alex wrote:
Hi all -

Getting ready for a ceramic tile install this weekend in my basement & ran
into a possible last minute "uh-oh"

...I'm installing 13x13 tile using VersaBond thinset from Lowes over part
of the concrete slab in my basement. Someone just mentioned to me that it
can't be installed over a sealed concrete floor.

I _think_, but am not entirely sure that the floor was sealed after it was
poured around 10 years ago. On the VersaBond bag it does say to remove
sealant before applying.

I did a test with some water on various parts of the area I'm going to
install the tile. When I poured the water onto the concrete it did pool a
little... but after it either all soaked in (for smaller pours) or I wiped
it up (on the larger pours), it did leave the concrete a wet color. Some
of the dark areas were uniform in color, others had a snakeskin sort of
pattern going on.

Will I be ok putting down the thinset as long as liquid does absorb into
the floor - and leave it discolored - basically leaves a 'wet spot'?

Thanks!

I've installed tile over concrete before and never had problems. As
long as the basement floor is not painted or at the very least the
surface "roughed up" a little, the thinset will adhere with no problem.