These measurements are for designing furniture for average sized adults, 10 and 5 year olds . If seats have cushions you must allow a half cushion addition seat height to allow for the weight of the person settling in the cushion. Again these are averages for a dining or desk type chair… we also offer some suggestions for various specialty pieces after the chart.
Seat Angles –
For formal sitting – have front of seat about 5 degrees higher than back of seat – seat and chair back 90 degrees.
For relaxed sitting – chair back tips back about 10 to 25 degrees from vertical – seat angles upward towards front 5 to 10 degrees. be sure to lower seat height to fit raised front.
Dining chairs with arms tend to be a bit deeper at base of legs (22 – 28″) than without arms (16-20″) for a more stabile seat. the width of the chair outside arm to outside arm is generally 20 to 27″ so of course these take up more width than an armless chair.
Easy chairs tend to have a 16″ seat height, angled 10 degree toward the front of the chair benches and sofas tend to be about an inch lower in seat height. Allow 24″ minimum per person for benches or sofas
Bar Stools should never have a seat height above 30″ and should be figured to be 12 to 15″ below the top of the bar. Most bars average 40 to 44′ high. The seat should be 16 to18″ square or about 17″ diameter. a rung should be placed about 20″ below the seat for feet. The dimensions of the base of the feet should be about 17 x 17 to 18′ by 18″ for stability.
Fitting Tables to Chairs –
Most dining tables and desks have a height of 29′ from floor to top. The average depth from the floor to the apron or frame of the desk or table is 25″, but this must also take into account any arms on the chairs. Be sure they will fit under. The top of the chair seat (with the cushion compressed) should be about 12 to 13″ below the top of the table.
For children, the table top should be about 23″ for 10 year olds and about 20″ for 5 year olds. Allow 10″ between the top of the table and the seat.
Coffee Tables average between 16 and 17″ high and should be about an inch or two higher than the seat on the sofa. Average top dimensions are 19 to 27″ wide by 36 to 60″ long
End tables average 16 to 17″ tall but if you are making one for a certain lamp, plan the table to have the bottom of the lampshade at eye height while sitting. Most end tables average 22 to 24″ wide by 24 to 28″ deep.
These stand behind a sofa for a lamp or decoration. Generally they are 26 to 27″ tall, depending upon the sofa, and only 14 to 17″ wide. The length should be about 3/4 of the sofa and average 60″.
Note: We realize that most woodworkers do not make furniture, but these dimensions are good to keep in mind when making accessories too. For example, if you are making a lamp. Use the info above to plan the bottom of the lampshade at eye level when sitting in a nearby chair. These are also great to up size or downsize a plan to fit older or younger children as the case might be.