Bricks, Masonry, Asphalt and Concrete - fixing a leaking painted concrete wall

Hello: Can you help me. I manage a small apartment building, built in 1928. It has concrete and lathe walls, and hardwood floors. Today, we discovered water on the hardwood floor near the base molding on a top floor bedroom. We surmise that the problem is that the old concrete has become porous, and needs some sort of coating to seal it on the exterior. There are no holes on the outside or cracks that we can see. The only thing I found is for unpainted concrete floors. The area in question is about 25 feet above the ground. Thanks, Kynthia

Concrete is naturally porous.

You need to find the source of the water, before worrying about sealing concrete. The water may be entering through a leak in the roof, leaking water pipe in the wall, or other such.