Extensions aren't built on empty land, every wall, footing, and roofline has to tie into a house that's already standing, and often out of square. That connection point is where the real risk sits, degraded footings, non-compliant framing, a roof junction that was never properly weatherproofed, and it's usually invisible until the wall or roof section actually comes off. Once it's open, you've lost your leverage to negotiate, and homeowners' biggest fear is exactly that moment: a fixed-price job suddenly turning into a blowout over "unexpected" underpinning or structural remediation. Every structural sign-off on your job is handled by registered DB-U builders. Where insurance requirements apply to the project, those requirements are identified and dealt with as part of the contract process.