Dampness of Wall and Roof

Condensation - is there enough ventilation?

All concrete absorbs moisture and water.

What's the slope on the roof?

Is there a roofing membrane in place atop the RCC structural element? If yes, is it intact and free of tears, rips, open seams and punctures? Also, is there metal flashing provided at parapet walls and any other vertical surface that comes into contact with the roofing? If yes, there is metal flashing present, how far above the flat roof surface is the roofing membrane up-turned...ie, distance it goes up the wall or any other vertical surface? How is any flashing material anchored into parapets and/ walls? How far up the wall is that location typically?

Last time any known maintenance was done on the roof system to make it weather-tight?

Are the rainwater gutters and downpipes in good order?

Moisture will migrate from warm to cold so ensure there are vapor barriers to block the moisture travel. Where the barrier is located and its permeability is a function of climate, the characteristics of the materials that comprise the assembly and the interior conditions.

Following is an excellent article regarding moisture control:

http://www.buildingscience.com/documents/digests/bsd-106-understanding-vapor-barriers/files/bsd-106_understanding-vapor-barriers.pdf/attachment_download/attachedFile

Would it be possible to see some interior and exterior photos of the flat? It would also be nice to know your location and climate. Condensation, wind driven moisture, heat wicked moisture or simple wicked moisture through leaks in the roof membrane are all possibilities. More info is needed.

Try Belzona Clear Cladding..It works perfectly in situations like yours.

a reply from the originator to the questions asked would be nice so a fuller picture can be drawn.

If you have a Radiant Control Coating on the exterior (wall, roof or both?) and that coating is worth its weight, there should not be any moisture on the interior of those walls or the ceiling.

Heat travels towards cold. Heat energy produced in the interior of a building will travel to the colder wall and ceiling surfaces along with the air and any humidity that is present. I will assume your walls have no insulation besides the Radiant Control Coating on the exterior. If your RCC coating is a good one, it should stop that from occuring.

Normally, this sweating on the walls goes hand-in-hand with a mold problem. Do you also have that going on?

I have had excellent results with an RCC on exterior stucco walls that had no insulation in them. I can direct you to them if you would like.

ceramatech_engineering@yahoo.com

If you have damp spots on your ceiling, there is water entering the structure and likely migrating to an area above the ceiling material before settling there and weeping

through the ceiling material. Only wind driven water will climb uphill, so if this problem only occurs when it is both raining and windy, look at both areas above and below the damp areas. If the dampness occurs when there is no wind accompanying the rain the leak will be found either above or at a very close proximity to the area where the dampness shows up. The water can travel horizontally. I have seen residential roofing repaired many times without success. Where ridges meet and where valleys meet at a ridge, the methods of construction become complicated. These kinds of unions require the skill of a journey man along with specially prepared break metals and flashing.I suggestion youcall ax inspector to e xam ine thr work

But almost wants j