McCallum Aluminum Ltd. is one of London's longest-established exterior renovation companies, proudly serving homeowners throughout Southwestern Ontario since 1957. As a family-owned and operated business led by Brian Hollis, alongside Diane Hollis and Kyle Hollis, the company has built its reputation on honest advice, quality products, and skilled installation services.

The company offers a comprehensive range of exterior home improvement services, including ENERGY STAR® certified replacement windows, steel and fiberglass entry doors, sliding patio doors, garden doors, premium vinyl siding, soffit, fascia, seamless eavestroughs, shutters, and custom exterior renovations. McCallum Aluminum provides free estimates, written guarantees, and installs products backed by leading manufacturer warranties.

Known for avoiding high-pressure sales tactics, the company emphasizes personalized customer service and quality workmanship. Its showroom in London allows homeowners to explore available products and receive one-on-one guidance for renovation projects.