If I understand the seasons in India correctly, you have already been through the rainy season. Don't wait until the next rainy season to get the problem with your drainage fixed. Now will probably be the ideal time to get it fixed. Please get someone who will tell you what to do and then have the work done. The paint on that wall in your beautiful home will keep coming off!

I think we scared away shilpasharda...I too think the dampness must be dealt with first. No reason to apply new stuff if it is going to be infected with mould, peel off and cause health concerns. Fix the problem not the symptom.

Thank you Groveraxle for the virtual ! you are too good a designer that is why I cannot help troubling you ;) you have your biggest fan in me ever since your first advice:)) As for an in-house designer I am certainly going to call somebody soon . Just that I get such a lot of options and great advice from highly accomplished and talented Houzz designers ..I would be better prepared after these conversations ..please forgive me for pestering you guys like this:)

The wood has to reach what's called Equilibrium Moisture Content (EMC), which is different for various areas of the country/world. I don't know about end grain slabs, which is what you have, but the rule of thumb for lumber air drying (vs. kiln drying) is 1 year for each inch of thickness. Moisture leaves the end grain faster than the side and/or edge of the boards, so in your case the drying time will probably be shorter. If it is not dried in a controlled environment your slabs are going to split radially, due to drying too fast.