Hi Daang,

Thanks for all the good advice you've given here. I wish I actually found this thread or did some studying on roof repairs before I hired my contractor, but I've made many noob mistakes and is suffering now because of it. I trusted my contractor on everything he said - and yet now have serious doubts on his guarantee.

Initial problems:
1. There were ceiling holes and water leakage and yellow patches on my car porch and master room toilet ceiling at the front of the house.
2. there are further 3 random spots on upper floor ceiling that has yellow patches

My contractor came and review and advice me since the leaking are at different locations, to waterproof the roof to prevent future and more serious damage from the leakages. He also patched the ceiling holes.

Day 1 & 2 : Applying the bitumen coat. He did this during a cloudy and occasion rain condition. He mentioned that the little bit of rain will not affect the waterproofing.
Day 4 : He patched the ceiling holes.

My problem came 1 month after the repair with the patches that he did on the 2 biggest holes - they started cracking and big "flat" bubbles start forming.
My contractor said this is not a problem of leakage (because he said his warranty only guarantee any further leakages, but not the patching of ceilings), the cracks/holes he patch is already done to their best capabilities - he cannot guarantee that the patches will last.

I would like to ask your advice what are the possible cause of these cracks + bubbles - is there any way to proof that the issue is because of his bad handiwork so that he will fix the problems as part of the warranty? I have found out that i seriously overpaid him compared to market rate and felt deeply unsatisfied that issues are already popping up in just 1 month after the repair and he is now saying his warranty does not include fixing the ceiling patches, but only repairing the roof if it continues leaking.

Thank you and sorry for the long post.