Insurance is one of the least glamorous parts of building an ADU, and also one of the easiest to get wrong. Here's a plain-English rundown of how coverage typically works, so you can have an informed conversation with your own insurance agent.
If your ADU is used by family members — a parent, an adult child, a guest suite — it's typically covered under your existing homeowners policy, though you may need to increase your dwelling coverage limits to reflect the added square footage and rebuild cost. The moment you rent the unit to a non-family tenant, that changes. Most standard homeowners policies either exclude or sharply limit coverage for rented structures, which means a claim involving your tenant's unit could get denied entirely if you haven't updated your coverage.
Once you're renting the unit out, you'll typically need a landlord (or "dwelling fire") policy specifically for the rented structure. These come in three common tiers:
Which tier makes sense depends on your risk tolerance, the unit's value, and your budget — this is exactly the kind of decision to make with a licensed agent rather than guess at.
Beyond basic property damage, a landlord policy typically covers damage caused by tenants (as opposed to the family-use assumption built into a standard homeowners policy), and often includes loss-of-rental-income coverage if the unit becomes uninhabitable and you can't collect rent while it's repaired. Liability coverage for tenant injuries on the property is another piece worth confirming explicitly rather than assuming it's included.
Adding ADU coverage, whether as an endorsement to your existing policy or a separate landlord policy, commonly adds somewhere in the range of $200-$1,200 per year to your overall insurance costs, depending on the unit's construction cost, whether it's attached or detached, and the coverage limits you choose. Get a specific quote before you finalize your rental pricing math — it's a real number that affects your actual return.
We're happy to walk through what type of structure your ADU will be (attached, detached, or garage conversion) so you have the right details to bring to your insurance conversation — that's part of what we cover during your free site visit.