L-Shaped Room Area Calculator

Maybe your floor plan isn’t actualy like your apartment at all. Maybe it’s an L-shaped room, but you’re used to working in rectangle. That creates a math problem when calculating square footage.

Most folks takes their measurement from the longest wall(s), and multiply accordingly. What they get is bunch of flooring materials for a non-existent box. It leaves you either without enough (or too much) material for the job.

How to Measure an L-Shaped Room

Enter the L shaped room area calculator, which will do the math for you! No need to guess, no need to convert measurements. Measuring are done in one of two ways.

You can measure around outside, then subtract out the space in the empty corner. Or you can measure each leg of the L by itself. Either works; both ways give you different perspective.

If you imagine a square with a chunk removed, that’s the intuition behind the subtraction method. For complicated arrangements, such as this one, the two-rectangle method are safer. It measures what’s there instead of what’s not there.

Be careful, though: you don’t want to count twice the overlap. That’s a common mistake. Someone add up the areas, forgetting that part of inside corner gets counted twice. The result is an overestimate of total area.

But by far the biggest variable in your budget is this: waste factor. Flooring isn’t one seamless sheet. It’s made up of separate pieces which must be cut. How much additional material do you need? Here is reference table:

For example, a straight run may have an additional five percent needed. A room with lots of closets or a diagonal layout may call for fifteen percent.

Direction also matter for aesthetics and waste. To make the room appear larger, run boards parallel to longest sight line. That means more angled cuts. More angled cuts = more scraps.

And if it’s an expensive hardwood, then the waste allowance is an insurance policy, so you don’t get a color mismatch if you need to purchase new batches over time.

Geometry also doesn’t consider clearance. Sure, you may have appropriate amount of square feet, but maybe its a narrow space. Think about swing of doors and walking areas around furnitures. Subtract furniture foot prints from the calculator.

A good rule of thumb is 30 inches for enough walking area. Without enough space you can never move well. It is a small detail, but it matters. Next time you attempt to scoot a chair you might realize there isn’t enough room.

Inside corners are typically the tightest path. There is less width here and furniture wants to crowd in.

Consider it a volume, as well. How much trim is needed? It depends on the perimeter. A rectangle of equal size different than an L-shape will have more perimeter. This means there is more wall material and more edge. This creates more opportunities for error.

Floating floors requires expansion gaps at the walls. To figure out how much floor to allow for expansion, you’ll need to account for net interior area within the trim line. This ensures that in changing humidity conditions, the floor have enough space to move freely rather than buckle.

There’s some arithmetic to measuring an L-shaped room, for sure. But it’s more of a visual exercise then anything else. It involves mapping physical space onto a grid.

The calculator give you the figures. You supply the context.

Watch your waste, check your corners. Honor the clearances.

Do this right and what was an odd shape becomes a feature. What was a missing corner becomes a house.