Wheelchair fit is decided at the narrowest point on the route she actually uses, not at the widest room in the house. The chair you pick has to pass through the front door, the hall, the bedroom door, the bathroom door, and every turn between them. Measure those points before you order, and bring the numbers to the seller.

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Measure the chair and the chair space

Get the overall width and overall length of the chair with its footrests and armrests in the position she uses. Some specifications list the folded or the seat-only size, and those numbers are not the ones that matter. Ask the seller for the full-width number. Write it down with the footrests in place.

Measure the doorways

Measure each doorway at its narrowest, with the door open to ninety degrees. The clear width is measured from the door stop on one side to the edge of the door or the frame on the other, not from wall to wall. Measure the bathroom and bedroom doors separately, since older doors are often narrower than the rest of the house. Note any threshold that rises above the floor, and measure its height.

Measure the hall and the turns

Measure the width of each hall. Then measure the turn at each corner, because a hall can be wide enough to walk down but too tight to swing a chair around a corner. Check the space at the foot of the bed and at the side she transfers from, since a chair that fits the door can still leave no room to pull up alongside the bed.

Walk the route with tape

Use painter's tape on the floor to mark the chair's full width and length. Stand in each doorway and each corner and check the tape against the walls and the frames. Push a box or a sturdy stand-in through the route to see where it binds. If you can get the actual chair in the house before you commit, do that. A walk-through with the real chair is worth more than any number on a sheet.

What to ask the seller

Ask for the full-width and full-length specifications with footrests in place. Ask whether a narrower or folding model is available for the tightest door. Ask whether the chair can be taken apart to get through a door, and who does that. Ask what the return rule is if the chair does not clear the route, and whether the return pickup is free. Get the answer in writing before the order is placed.

What to decide before it arrives

Decide what moves out of the way. A small table in a hall corner, a rug on the threshold, or a door that can be removed from its hinges may be the difference between a chair that fits and one that does not. Write the plan on the day sheet so the person who sets the chair up knows where it goes and what has to clear first.

The Chair You Want May Not Pass Your Hall. Walk the Route With Tape Before You Order.