The house is going to be smaller than our current home, all one level, energy efficient and all that, but what would you add into the design knowing it was going to be a house you planned to age in?
There are so many little changes to be done, that can make a huge difference. The prior owner of my house was elderly and disabled, so many of the changes had already been done when I moved in. At 69, I already appreciate many of these accommodations even though I probably don't totally need all of them already. The following is a list of things she had already done to my house, for the most part, and I probably forgot some but here you go.
GENERAL: Some important things to think of before your house is built, would be sufficiently wide doorways (and hallways, if you have them) so that you can get from the living area, to your bed, to the bathroom, toilet, and roll-in shower, easily even if using a wheelchair or walker. My house has the lever handles on all doors. Even though I have zero arthritis in my hands and don't need them, they are fine and I don't even notice them so I think that's a good idea too. If you choose carpet, you might want to pick something with a very low pile so that wheelchairs, walkers, or carts can glide over it smoothly.
BATHROOM: Put solidly anchored grab bars not only in several locations in the shower, but also on the wall in other parts of the bathroom, near the toilet, and so on. These can help to steady you and help to prevent falls. I joke that the grab bars in my bathroom are anchored to the center of the earth and sturdy enough for a sumo wrestler to do handstands on them, but really, they should be awfully sturdy like mine and this would be easiest to arrange when building the home I would think.
SHOWER STUFF: A built in shower bench at least 20"-22" high would be nice for the elderly with sore knees, with grab bars placed to help them stand up from it. Something I like about my shower is that it not only has the shower massager (on an extra-long hose), but also it has several different thingies on the shower wall where the massager end can be hung, either for usage as a shower head for different height people or to be easily reached if one is sitting on a shower bench or seat in there. Think hard about grab bar placement, size, and orientation so that an older person could hold two of them, not just one, when standing or getting into or out of the shower.
EXTERIOR DOORWAYS AND GARAGE: Think about getting into the house and out of it. You probably can't make the entry perfectly flat, but there is no need for any extra steps to navigate. My house has a waist high metal table just outside the door with a sturdy wooden rail on it. I can put items down on the table so that my hands are free; thus I can hang on to the rail while opening the door, stepping up the two very low (2"?) steps, and stepping through the doorway. This has already been very helpful to me for fall prevention. Also, the concrete from my back door to the door of my garage is perfectly smooth and not steep; it would be easy to navigate in a wheelchair, or when pushing a cart with items being taken to or from the car, or whatever.
KITCHEN: In the kitchen, remember that some with severe arthritis or other conditions find it difficult to deal with cabinets that are very high or low. Include some pantry cabinets that have shelves that are conveniently waist high, that could be used instead. Include an island or kitchen bar area where you could sit while preparing food, in case it becomes more difficult to stand for a long time as you age. And definitely do install deep drawers instead of lower cabinets.
BEDROOMS: I can't think of much here, except that wide closet doors might make it easier to access clothes if wheelchair bound. I have double doors on my bedroom closets.
LIGHT FIXTURES: When your ladder climbing (or stepstool climbing) days are behind you, you will really appreciate being able to change lightbulbs in your light fixtures while standing flatfooted on the floor. My overhead lights are ceiling fans with light kits and so I can do that.
YARD: And yes, do insist that your yard is xeriscaped or whatever requires the least work in your climate. In the New Orleans climate we have a huge annual rainfall, along with an overabundance of sunshine and heat. Grass grows like crazy here, with no need for watering or fertilizing. So, I have nothing but grass growing in my yard, and a lawn guy to mow and edge it. All I do about the yard is to pay him. I have done absolutely zero yard work myself, in the past three years.
Something that isn't done already to this house, that I will be thinking of in the next few years, is some way to open or close the blinds remotely instead of having to get up and do that when I am a billion years old. I'm sure there must be some way.
Hope this helps.
