Enter: Aeroseal, a Bill Gates-backed startup that sprays a mist of its proprietary sealant — made with a material similar to chewing gum — into a home's air ducts to seal gaps and other cracks.

Two exhaust stacks with Vanstone angle rings were also essential to complete this project. Linx Safe for double-wall duct is an internally insulated and self-sealing duct system that delivers ...