If you do not have at least 40% savings on the energy necessary to heat and cool your home during the first year after installation, The Window & Door Store will refund the difference, up to a maximum of $500.00. To make a claim for a refund, contact The Window & Door Store for an Energy Savings Guarantee Refund Application. The Window & Door Store guarantees a 40% savings on the energy necessary to heat and cool your home during the first year after installation, when you replace all of the windows, patio doors, and exterior entry doors in your home with our premium windows with a triple pane glass system. In the event that less than all of the windows and doors are replaced, this guarantee will be prorated to the actual percentage of the windows replaced.