Laneway housing is a terrific option to deal with aging boomers and their children.

After years, no, decades of opposition, laneway housing is finally legal in many cities, thanks to the cost of housing and the aging of the baby boomer generation, who are often owners of lovely houses with generous backyards. These new, small laneway houses can become a place for them to downsize, or to provide living space for their kids.

The owners of the lot where the Alley Cat wanted a place for themselves while renting out their craftsman style house in front. In Seattle, it is called a DADU, or Detached Auxilary Dwelling Unit; Shed Architecture and design write that "the client requested a unique structure that was low-maintenance and PV-ready, easily accessed from the alley and with a strong relationship to their existing garden. In addition, the client was hoping for an interior space open to the sun, and with primary rooms on one level for aging-in-place."

The exterior is clad in basic, maintenance-free standing seam metal and not a lot of windows, to maintain privacy for both the people living here and those in the main house.

The only big open at grade is a giant sliding door opening on to the garden at the side; having a big lot like this certainly helps.

The interior is mostly lined in plywood, which " captures warmth and durability while white walls high above reflect light throughout the spaces"– the architects describe it as "hard on the outside, warm on the inside."

I am naturally drawn to this interior, given that I share the love for midcentury modern furniture, have some of the same chairs and even the George Nelson bubble lamp over my dining room table.

The design for aging in place is also done really well, very subtle, with wide doors and a big bath and open shower that doesn't scream "aging in place" – it's a good example of universal design. I actually think it is the smartest way to design a tub and shower, and did it a few times as an architect as well as in my own home. I do think they put the bathroom taps in the wrong place, it is a long way to reach across the tub. I combined them so you don't have to reach.

This lovely 800 square foot house won't be cheap, laneway houses never are. As we noted when discussing Lanefab's houses in Vancouver, "you have all the same stuff as in a bigger house, more difficult access, often complicated designs and expensive servicing of water and drains." But if you have the land, and live in a hot city like Seattle, you still come out way ahead.

Over the next decade, there is going to be an explosion in the number of baby boomers who want to downsize. Over the next week, there's going to be an explosion in the number of grown kids moving home. Laneway housing can't solve either problem, but it can make a dent in it. Shed's Alley Cat is a great demonstration of how to do it right– how to be deferential to neighbors, how to design a simple, elegant space that can be used by anyone, and how to make 800 square feet feel like so much more.