Have you heard of ADUs? If you’re not quite sure what they are, you’re not alone. ADU stands for Accessory Dwelling Unit, and they’re becoming more popular across the country as communities look for ways to make housing more affordable. They can provide flexible housing for families and, in some cases, even create additional income.

So what exactly is an ADU? It’s a secondary living space on a residential property — sometimes a converted garage, a basement apartment, or a small standalone structure. For many families, an ADU is a wonderful option when you have aging parents or adult children who need to be close by but still want their own space.

Where are ADUs allowed? This is the important part here in Wisconsin. ADUs are permitted in some communities, but whether you can build one depends on your local municipality’s zoning ordinances. There isn’t yet a statewide law that automatically allows them everywhere.

That said, it’s an area worth watching. During the 2025–26 legislative session, Wisconsin lawmakers introduced and debated bills that would require communities to allow at least one ADU on residential lots as a permitted use. Even under those proposals, local governments would still be able to regulate details like size, height, and setbacks, and could prohibit ADUs from being used as short-term rentals. As of now, though, nothing statewide has taken effect, so your local rules are what matter.

Would your property even qualify? ADUs aren’t right for every lot. Several factors affect whether one is possible, including lot size, zoning, parking requirements, utilities, and — especially on rural and lake properties around here — septic capacity. It’s a lot to sort through before you invest in any plans.

That’s where we can help. If you’re wondering whether your property might qualify, we’d be happy to help you understand what your local municipality allows before you spend any money on drawings or design. Sometimes a quick conversation up front saves a lot of time and expense down the road.

Derby Realtors at Shorewest — your local team, ready to work hard for you.