LOOK TO US FOR DOOR AND WINDOW INSTALLATION SERVICES IN CASPER, WY You can trust a general contractor with 35+ years of experience Replacing your damaged doors and windows can increase your property's energy efficiency, enhance your sense of security and boost your property value. Turn to Mountain West Building & Design in Casper, WY for expert door and window installation services. We believe in treating our customers right, so you can expect us to finish your project with care and professionalism.