How to Measure a Room for Flooring

As everyone knows, the first thing homeowners should do when considering making any decorative change to any room is to measure it so that they know what they have to work with and what their limitations are.

Replacing the floor of a room is one of the tasks in which measuring becomes absolutely crucial to the completion of a high-quality job. The new flooring has to completely cover the relevant surface area without any visible joins for the most attractive effect, so it is imperative that the right measurements are ascertained before any flooring is purchased.

However, many rooms and areas can be complicated to measure accurately for a number of reasons. This guide should help resolve any confusion.


Measuring the area of a room

  • To calculate the area of a perfectly rectangular or square room, you can simply use the (length) multiplied by (width) formula to arrive at an accurate answer.
  • If a room is 4m wide and 5m long, therefore, the surface carpet area to be bought will be 20m².
  • You can then work out how much your carpet will cost, as they are usually assigned a price per square metre purchased.
  • Use a tape measure and calculator to achieve the most accurate results, though you will need a partner to hold the other end of the tape measure.
  • Measure to the back of any doorframes leading in or out of the room so that the carpet can be fitted into the door.
  • The same technique can be applied to hallways and landings.
how to take accurate floor measurements guide

Indentations and recesses

Indentations and recesses

Unfortunately, not every room is going to be completely rectangular – bay windows, fireplaces, wall supports and other indentations or recesses can distort the shape of the room, meaning that carpet and other flooring materials must be cut to fit around them.

They should not affect the total area of carpet to be bought, however: measure the lengths of the unaffected wall areas and then the length of the indentation or recess. Add them together and you will have your total length.

If the room has a U-shaped end or a round recess, this throws up certain complications in terms of calculating the surface area, but they can be solved without too many problems:

  • Measure the length and width through the middle of the recess.
  • Divide the length in half and multiply that number by the width.
  • Calculate the total by 3.14 (pi) and you have the complete area of the circle.
  • However, only half of the circle extends past the wall boundary, so divide the number in half for the area to be covered.
  • You can then add that number to the other area totals for the room.

Measuring the area of a staircase

Staircases look tricky to get right when you measure them, but they are actually relatively simple. Simply measure the lengths of the tread (the top of the step) and riser (the front of the step) of the first step, and then (assuming they are the same) multiply the figure by the number of stairs to be covered, discounting the top stair as it will be covered by the landing carpet. Although the stairs may require a join or two, these can be concealed at the point the tread and riser meet.

Winding stairs can be more difficult, but remember to measure the widest and longest parts of each stair for the most accurate finding and they should not present much of a challenge.

Measuring a landing

Measuring a landing

Landings are generally difficult to put down new flooring on because they tend to be shaped like a capital “L”. This is not helpful if you are trying to avoid joins, which take away from the attractiveness of an area when you use several pieces of carpet rather than one.

However, it is possible to achieve a one-piece covering of the landing and stairs when you know how much you can cut out. Calculate the landing area in two or three sections and then add them together to find the full area.

The landing carpet opposite the staircase should always be long enough to go over the top stair so that it goes down to the base of the first tread.

Measuring for different flooring materials

Measuring for different flooring materials

Wood

Wood flooring is usually sold in packs divided into square metres, so you will need to ensure that you know how many packs have to be purchased for your room. If possible, ensure that the grains on the different planks run in the same direction to give the room a sense of coherence.

Divide your room area size in square metres by the number of square metres of material in each pack to find out how many packs you will need to buy.

Example: if a room is 20m² and each pack has 4m² worth of material in it, you will need 5 packs because 20 ÷ 4 = 5.

Laminate

Laminate flooring is usually sold in packs divided into square metres, so you will need to ensure that you know how many packs have to be purchased for your room. If possible, ensure that any grains or patterns on the different planks run in the same direction to give the room a sense of coherence.

Divide your room area size in square metres by the number of square metres of material in each pack to find out how many packs you will need to buy.

Example: if a room is 20m² and each pack has 4m² worth of material in it, you will need 5 packs because 20 ÷ 4 = 5.

Carpet

Carpet is usually sold in standardised rolls that are 2, 4 or 5m wide, so if the area to be covered exceeds 5m in width then a join will have to be created. However, the effect of the join can be lessened by careful placement and ensuring that the roll widths are the same. This ensures that colour shades remain as close to each other (if not identical) as possible.

Any pattern should also run in the same direction – not only is it aesthetically problematic if they do not, but light will also reflect differently around the room.

Measuring for different flooring materials Measuring for different flooring materials Measuring for different flooring materials

In addition, when you purchase any type of flooring material, it is worth adding 5-15% more than you need to the order. This will ensure that you are covered against any small mistakes or complicated cutting you might have to deal with.