Design Math: Guide for Bedrooms & Living Spaces

Design Math: Guide for Bedrooms & Living Spaces

We’ve found the numbers you need to know to create inviting bedrooms and living spaces. From arranging furniture to hanging frames, design duty is about to get a whole lot easier. Turn to these digits to ensure your rooms measure up.

Living Spaces

  • TV: Multiply your screen’s diagonal measurement by 1.5 and use that as the smart distance from TV to sofa or chair. There should be about 7' between the TV and seating options.
  • Mirror: The perfect space between a mirror and the top of a mantel is 7”.
  • Coffee table: Designers agree -- a coffee table’s height is important. The standard height: 16-18”. It should be no lower than 1-2” from the seat of your couch. (A higher sofa requires a taller table, up to around 20-21”. A taller table is more convenient if you frequently entertain – aim for just the right height to set down a drink.) A few inches lower, however, is great for putting up your feet. Coffee tables should be placed 12-24” away from your couch.
  • Art: When hanging art over a piece of furniture, a good height to aim for is 24-36”, depending on the height of the artwork itself.
  • Frames: When hanging frames or a series of pictures together, keep 2-2.5” between pieces to keep the look cohesive. The grouping should be no more than 6” apart. 60” is good height for mirrors and other hanging art. (To get an eye-level view, measure from the floor to the center of what you’re hanging.) 
  • Furniture: Never push couches or chairs completely up against the wall. By pulling your seating arrangement in (even just one to two inches), you’ll create air flow and warm up the space. In large open spaces aim for 36” between furniture and the wall.  This creates a more intimate and inviting conversation area. Chairs sitting next to each other should be about 42” apart.  
  • Outlets: Install an outlet 28” high behind console tables to avoid tangled cords.
  • Area rugs: Allow about 24" between the wall and a room-size rug in a large room, and between 12-18" in a smaller room.
  • Hallways: Instead of installing wall-to-wall carpet in a narrow hallway, use carpet as a runner and leave at least a 3” border to make the space seem wider.

This Old House - livingroom
This Old House


  • Nightstands: The sweet spot between a bed and nightstand? Around 2”. Nightstands should be 36-38” tall. This height ensures the best light from the beside lamp.
  • Headboards: A standard headboard is 48” high.
  • Beds: Keep beds about 23” inches off the floor. A bench at the foot of the bed should be 2” shorter than the mattress width.  For ideal bed placement, allow at least 24” between the bed and the wall to get out of bed comfortably and allow 36 “ between the end of the bed and the bedroom or bathroom door.
  • Doorknobs: Doorknobs are typically at 36”. Some designers recommend dropping them down to 34” for a more relaxed proportion that is easier on the eye.