I have a detached garage that must have been built on either a dirt floor or a long ago disintegrated cement floor. The cement pad in the garage is relatively new, but extends just up to the beams, not under them.

I'm noticing a lot of wood rot on the lower edges of the beams. Some of them have even been replaced recently (before I purchased the home), but they're looking 'fuzzy' too. I'm guessing that digging the whole way around the garage and having some flooring inserted and waterproofing done would be the best way to go, but financially, it's just not going to happen in the next year or two.

So, I'm trying to find the most cost-effective way to mitigate further wood rot. Would painting the bottoms of the beams with a waterproofing agent do any good, if I can't get under the beams where they sit on the dirt? Any suggestions for something I could try to push under the beams, or spray down there?

thanks in advance.