Help! Damp Hall with Condensation

The building is old? Maybe the isolating isnt good. You can only try to deal with the problem with solutions like the one you told and keep going but won't really manage to solve it from its root. Of course i could be wrong.

There are some "paints" chemicals that can be used also after the build proccess is over( They dont necessarily have to be some colour can be transparent). Thing is you won't be able to use it for some time and it will take you some hours to get it over 2 or 3 hands. Building is concrete right? If so then look for particular spots that the concrete isn't that solid. If thats the case you have to hit them with a tool and remove all of the easy to remove stuff. After you will rebuild using one of many products available.

If the building is old it would probably be a huge economical effort to change the insulation, if there is any. Those paints that were mentioned earlier are not the best option for old buildings because they don't let the materials "breath". You can deal with condensation using 3 methods: heating the environment, ventilating the room or dehumidify the environment. Usually none of these work to the extent we would hope to, but they help to solve the floor problem. Concerning the balls, i suggest that you keep them stored in cloths or something that absorbs humidity. You have to constantly clean your rubbers also.

You can try a dehumidifier, but you will need a commercial sized one. You can try de-humidifying decassants which look like tiny white balls. You put them in a container, they attract the moisture and it drips down those tiny balls into the container. You will need a LOT of those to treat a large TT hall. These are the stuff that is inside the air driers on commercial trucks with air brakes. if there was no effective way to dry the air in a truck air brake system, the moisture would play havoc clogging or gumming up valves. Also, when it gets really freezing, valves get stuck shut and the truck will not move.

You can also do it like Korean saunas do... they have someone with towel constantly wiping down stuff.

You would do well to wipe the floors a lot.

As for air humidity condensating on the playing rubbers, not much you can do except use rubbers that are very resistant to this. H2/H3 and 999 are two rubbers that endure this great. Tenergy and Omega II are among the worst rubbers to use in high humidity. Aurus does a fair job, but 999 and H3 are top shelf stuff for humid conditions.

Another thing that might be somewhat economical is RICE.

A lot of people put their I-Phones into a bag of it when they drop their phone in water.

I huge bag of rice per table poured in a huge stainless bowl under each table with a mesh lid taped to it doesn't cost an arm and a leg.

You can try getting agricultural drainage. Not an expensive process,and it works well.

Dampness goes away quite nicely with this method.