Can you build a PSL Modular unit in Connecticut?

It depends entirely on your town. HB 6107 (Public Act 21-29, 2021) made ADUs as-of-right statewide — attached or detached, up to 1,000 sq ft or 30% of the primary dwelling — but towns could opt out by January 1, 2023, and more than two-thirds did. About 54 towns kept the state as-of-right standard; roughly 115 opted out and wrote their own (stricter or looser) rules. So the first thing to confirm is whether your town opted out and what its current ADU ordinance says.

It does not mean ADUs are banned. Opting out simply means the town declined the state's default as-of-right standard and adopted its own ADU regulations, which may require a special permit or set different size/parking rules — or may actually be more permissive. Check your town's specific ordinance.

Modular units are built to the Connecticut State Building Code and factory-inspected by an approved third-party inspection agency; the local building official, under the Office of the State Building Inspector framework, handles the on-site approval and certificate of occupancy. Your local permit covers the site work — foundation, utilities, zoning.

Snow and cold inland (the northwest hills carry the heaviest loads), and along the Long Island Sound shoreline, coastal wind and FEMA flood elevation. Seismic risk is low. PSL Modular sets the envelope and any coastal/flood spec from your site.

Yes — Fairfield County's high housing costs (and NYC-commuter demand) make a rentable ADU compelling where the town allows it. First confirm your town's opt-out status and rules; then the factory-inspected unit moves quickly through local permitting.