The warranty will depend on the manufacturer. Most well-known uPVC manufacturers in Bangalore offer a warranty on their product as they are assured of the quality of the products on offer. Ask your dealer about the details on the warranty before you finalise your product. You must avoid going for a product that comes without a warranty as the warranty provides you with an assurance of replacement in case of any manufacturing defect in the product. Windows installation is an expensive proposition and must be dealt with caution.