Maryland ADU
Contractors
Maryland homeowners

A second home on your lot, done by the rules of your county

Seven Maryland counties now allow accessory dwelling units, each with its own bill, size cap and permit path. We lay out the rule for your county and connect you with a licensed Maryland builder who already does this work.

Who this is for

A parent moving closer, an adult kid who needs a door of their own, a rental that pays the mortgage, or an office that is not the kitchen table.

What we do

We read the county bills, keep the rules current, and match you with a licensed builder. The builder designs, permits and builds the unit. We never claim to.

What it costs you

Published Maryland ranges by unit type, county permit fees, and the sprinkler number, each with its source named on the page. No made up averages.

Pick your county

The rule where you live

Every Maryland county had to adopt a local ADU law by October 1, 2026. Some did years ago, some are still voting. Tap your county for the bill, the size cap, the permits and the cost.

How it works

Three steps, one builder

  1. 1

    Send the address and the kind of unit

    Backyard cottage, attached suite, basement or garage. Well or public water. That is all we need to start.

  2. 2

    We check the county rule

    Size cap, bedrooms, owner occupancy, and whether the unit needs a fire sprinkler system. You get a straight answer before anyone quotes.

  3. 3

    A licensed builder calls you

    One Maryland home builder who already does ADUs in your county walks the lot and gives you the price. No bidding war, no list of strangers.

Fire sprinklers

A detached ADU gets a sprinkler system in every Maryland county

Under the state building code a backyard cottage is a new dwelling and gets an NFPA 13D system; a basement or attached unit inside an unsprinklered house usually does not. Our sister company, Maryland Fire Sprinklers, designs and installs them, so the answer is on the table before the builder quotes.

Get matched

Tell us about the lot

Address, county and the kind of unit. We answer with the rule that applies and the name of a licensed builder who works there.

14 builders on the list, seven counties, one person reads every form the same day.

Call (240) 261-0261