I want to ask that is there any regulation that the developer will provide extra tiles that he used in common area at the time of handover of the project.
Not recently, but it was common to specify (part of the Contract Documents) that replacement tiles be provided. I've never seen it as a code requirement.
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It's very common that the architect will establish a quantity of reserve tiles but it depends on the type of tile. VCT from suppliers like Armstrong, Tarkett, Mannington, etc., have certain produce lines that remain active for decades, thus there isn't a pressing need to inventory extra tiles.
It's often prudent to buy extra material, if for no other reason than attrition and breakage, either in transport or actual installation; other reasons would include unacceptable variability of the material. We bought about 100 sf of extra natural stone tile, since the suppliers will often foist a few duds in a shipment to get rid of material that no one might otherwise purposefully buy. Natural material also often have defects or undesirable or unmatchable appearance. We had to destroy one tile because the dishwasher didn't have enough clearance after the remodeling due to the added hardyback and adhesive thicknesses.
TTFN (ta ta for now)
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