Interior Design Measurements

I’ve worked in the interior design industry for almost 20 years now, and in those years the same questions have come up over and over and over again. How big should my dining room fixture be? How high should I hang my art? What size rug should I get? Questions about sizes and measurements are by far the most common.

I’ve seen posts online about the standard measurements everyone should use, and many of them are great. But despite the abundance of information out there I decided to write my own, with some of my own ideas. I’ve been lucky enough to work with some of Canada’s best designers and stylists and they’ve given me so many great tips over the years, so it seems only fitting that I share. Obviously, these are not set in stone, and you’ll have to determine what works best in your own home, but keep these interior design measurements in mind when decorating.

Rug Sizes

Rug sizes have been confusing people for as long as I’ve worked in this industry, and the most common mistake people tend to make is to use area rugs that are too small. When in doubt it’s always better to go too big rather than too small. The measurements I’ve listed below won’t always work depending on the size of your room, but try some of these guidelines if you’re having trouble. And check out some more tips for choosing area rugs here.

8’X10′ – The ideal bedroom rug size if you have a Queen bed.

9’X 12′ – The ideal bedroom rug size if you have a King bed.

18″-20″ – The amount of floor space that should be seen between the edge of the rug and the walls in larger rooms.

18″-24″ – The amount of the rug should extend beyond each side of the bed.

24” – The minimum space behind a dining chair and the edge of the rug upon which it sits. 30-36” is better if possible.

No matter what the room, remember that all four legs of major pieces should be sitting on the rug. If that simply isn’t possible make sure that at least the front two legs are.

Arranging Furniture

Arranging furniture is one of the elements of decorating that continues to cause stress. For whatever reason people don’t seem to have a lot of confidence when it comes to furniture sizes and placement. With that in mind, here are some numbers that I hope will help!

12” – The ideal depth of a bookshelf (or 15” to fit oversize art books)

18” – The ideal distance between the couch and the coffee table.

22″-30″ – The standard/ideal height for end tables.

24” – The ideal distance between living room chairs placed side by side in a smaller room.

36” – The ideal distance between the wall and the back of a piece of furniture.

42” – The ideal distance between living room chairs placed side by side (so a table can fit between).

Hanging Art

Rooms with bare walls are generally not ok. Seriously. The minimalist look on the walls doesn’t work in most real homes. Unless it’s a very specific look, the result is generally cold and empty. But don’t be afraid! The below guidelines will help determine where to hang artwork – both single pieces and groupings.

2” – The approximate space that should exist between pieces of art hung in a group.

4″-6” – The ideal height above a dresser or table at which to hang art.

4” to 8”—The ideal space between the top of a sofa and bottom of a piece of art (single or group).

56” to 60”—The height to centre of artwork (or approximately eye level). When hanging two or more pieces of artwork, treat them as one large piece – find the centre point between them all and use the same rule.


Most rooms require a variety of different types of lighting (ambient, task and accent), all placed at different levels around the room. Here are a few tips for placement.

68” – The ideal height of a floor lamp (traditional shades will conceal the bulb at this height whether you’re seated or standing).

3” to 6” – The space between a wall sconce and the edge of a mirror or piece of art it’s flanking.

7” – The minimum distance the bottom of a hanging light fixture should be from the floor (if it’s in a space where people will be walking underneath such as entryways).

24″-27″ – The ideal height of a bedside lamp.

36” – The distance a light switch should be above the floor. And be sure to leave 1&1/2” to 2” between the switch and door trim.

30″-36″ – The distance the bottom of a dining room fixture should be above the table. The exception is with cathedral ceilings where you can go higher.

60″-64″ – The height at which the centre of the backplate of a wall sconce should be above the floor. This goes for entryways, bathrooms and so on.

Length + Width of Room – The ideal size, in inches, of an overhead fixture. So a 15’X15′ room should have a fixture approximately 30″ in diameter.

Window Treatments

In my humble opinion, no room is complete without window treatments. While I understand not wanting to block a beautiful view, I find rooms without window treatments cold and unfinished. In any case, here are some tips.

0” – The distance curtains should hang above the floor. They should always skim the floor, or for an elegant look, puddle slightly on the floor (approximately 2”). This one is a bit controversial, but I’ll never cave!

2” –  The minimum distance from the top of the window casing to the curtain rod. To create the illusion of a taller window try mounting the drapery rods close to the ceiling.

2.5x—Drapery panels should have a combined width of at least double the width of the window, but preferably a little more. If you have two panels each should be at least the width of the window.

4” to 10”—The distance from window casing to end of curtain rod (excluding finials) on each side of the window. The greater the distance the wider the window will appear. Use your best judgement in your space.

Some of these measurements you’ll find in other articles, but a few are a little unorthodox based on years of styling and decorating experience. If you have any tips or comments please feel free to share!

Photos courtesy of Income Property, Unsplash, Buyers Bootcamp & Pexels