Every single day people are talking about Auxiliary Dwelling Units in print, on the TV and Internet in just about every city, town and village in the US.
But trying to get those people to tell you what they are talking about is like asking what the color blue tastes like. There is no right answer. To further confuse you, here are just some of the most common terms being used today:
Accessory Dwelling Unit
Secondary dwelling unit
We’ll use ADU for this article.
Defining an ADU is no easy matter. Is it less than 8’ wide like a Tiny House or is it 399.9 sq ft like a modular “Park Model” or is it something larger?
You also have to know if your ADU will be legally allowed to be on the property where it’s set. ADU’s are expensive to build, often costing in the range of $40,000-$200,000. If it has to be removed from the property because it doesn’t meet local zoning, that’s a lot of money down the drain.
If it is allowed by zoning, does it meet the building codes for the planned ADU. There are three distinct building codes most often used in ADU manufacture. The first and toughest to meet is IRC just like any standard site built and modular home must meet. It comes with many code inspections during construction.
Secondly, it could be built to HUD specifications just like a manufactured home. Some call these mobile homes and even though our industry doesn’t like that term, it’s still easily recognized as the least expensive type of approved housing in the US.
And lastly, there is the “No Code” whatsoever ADU. Many of these can be found in alleyways or secluded backyards with electrical extension cords for powering the ADU and a garden house for water. Most of the time, the occupants will use the main house bathrooms and even the kitchen.
But no matter what you call them or to what code they are built, ADU’s are here to stay with many states, mostly in the West where affordable housing has all but dried up, leading the charge to allow them into R1 neighborhoods.
Watch for new modular factories to spring up across the country to meet the demand for ADU’s or Granny Pads or whatever you want to call them.