Every certificationthat matters— explained plainly.

Most retrofit installers hold two or three accreditations — typically just the ones legally required for the kind of work they do most often. We hold seventeen. The reason isn’t marketing. Whole-house retrofit involves gas, electrical, renewables, insulation, ventilation, hazardous waste, customer data, vulnerable tenants, public-sector procurement and the careful interaction between every one of those things. Each of those areas has its own standards body. Each of those standards exists because somebody, somewhere, was let down badly enough that the industry had to change.

What follows is the full list, explained plainly. Each entry tells you what the certification is, why it was created, what it specifically demands of us, what it means for private homeowners, what it means for housing providers and public-sector buyers, and where you can independently verify our registration.