GS Exterior Experts is a proud family owned and operated company specializing in home exterior services in Littleton, Colorado since 1999. GS Exterior Experts is a home exterior company specializing in siding installation, replacement windows, roof replacement, stucco and stone installation for residential and commercial projects in Littleton serving the Denver surrounding area in Colorado. We offer James Hardie Siding installation as well as Woodtone rustic series siding installation. If you are looking for energy efficient replacement windows we can help! We offer a full range of vinyl replacement windows as well as fiberglass windows and energy star rated products.