Help Needed: Roofing a Terrace

I own several buildings on slabs. mouisture is a real problem if you have no basement or crawl space under a house. Moisture builds up inside fast and takes a lot to get it out. Finding the true entrance for water can be hard. Often it is better to start tearing out where the water damage is and follow the damage to the entrance.

In my experience of housing I can make two suggestions. As you say that the water collection is prevalent in the hall-way I'm assuming that the hall-way is located in the interior of the buildings with flat concrete flooring. And secondly I am assuming that you are referring to dampness to such an extent that it could be called leakage, such as is possible through concrete structures. realisations with types of housing construction: I would like to ask weather the building are constructed with aluminium joinery, such as windows and door frames, sliding door and the like? These building methods seal the building from the normal breathing that a building constructed from wooden joinery does and therefore makes the building susceptible to condensation areas within it's structure and it would therefore become necessary to use "dehumidifiers" constantly to compensate for the heat exchanges from night temperatures to day temperatures which cause the condensation of the building that lacks breathing materials within it's structure especially concrete floored, walled or roofed buildings. These same problems are rectified by making the "flooring with built in hot water piping" running through them as my sister has in the past buildings. I imagine that your buildings would suffer from condensation more than leakage persay, as leakage refers more to a hole in the structure than anything else and condensation can amount to a greater quantity than one would expect. If in fact there is an underground water seepage I would suspect that it would be isolated to only one particular property and not on several properties as you wrote.

Roll Rubber works miracles on Flat pitches. If the water can't be shed you might try out smarting it and installing a drain pipe.

Built up roof system...with solid rubber membrane, goodyear makes the best product...no pun intended...the important thing with a concrete structure is to keep the water away from the foundation... all water to be shed at least 5 feet from footing...minimum...so to reiterate...sloped styrofoam roof pitched at least 1/4" per foot to a central drain which is to be drained away from foundation... the system works best when drain is central... find a good commercial roofer... for your bungalow it shouldnt run too much over $15.00 per square foot for material...the low tech choice...lots of tar in a can...