When doing home improvements you will need to know how to calculate square foot measurements. Having accurate measurements whether you're using feet, yards or meters, is necessary so as to accomplishing a cost effective timely project.

Below you will find advice from how to measure wallpaper, to the amount of paint you're going to need to get your wall painting idea completed.

For the best results be sure to use a good quality measuring tape or yard (meter) stick.

Also, when it comes to painting and decorating measurements try, whenever possible, to round up to the nearest foot.

Another thing to keep in mind, make sure you buy a little extra of the material being used.

Otherwise, it might be frustrating having to drive back to the home improvement center for a quart of paint or roll of painters tape.


Before you can figure out how much material you require, you will need to calculate square foot measurements (or meters) of the surface area that is being covered.

A floor or ceiling can be easy to figure out. Just multiply length times width. As an example, if your living-room is 15 feet long by 20 feet wide the calculation would be 15' x 20' = 300 sq ft of floor or ceiling area.

Walls can be a little more difficult to measure, especially, when you're considering decorating an entire room. To figure out wall area multiply height times width of each wall section, from corner to corner. Once you have calculated each section add the calculations together.

Here is an example; if the living-room mentioned above is a rectangle room with 8 foot high walls then the calculation would be as follows.

Two walls at 15' (long) x 8' (high) = 120 sq ft of wall area + two walls at 20'(long) x 8'(high) = 160' of wall area or 120 sq'(wall #1) + 160 sq' (wall #2)+ 120 sq'(wall #3) + 160 sq'(wall #4) = 560 sq'. So what that means is you have 560 square feet of wall area to coat or cover with product or materials.


When I calculate square foot measurements for walls I don't normally subtract areas like windows and doors. By not eliminating the windows and doors, I'm assured of extra product or materials for the project at hand. Having a little extra of the material being used will keep you from running out of product in the middle of a job.

With that said, if your room has an inordinate amount of doors and windows etc., or you're going to hang very expensive wall covering, then go ahead and figure out what needs to be subtracted from your estimated surface area.

As you do your subtraction keep in mind a standard door is 21 square feet and a standard window is usually around 10 to 12 square feet.


When there's a round wall in your home or if your trying to figure out a circled exterior surface, you will need to know how to calculate square foot measurements that have odd shapes.

For irregular shapes and sizes use the calculation tools link below to help you get those gable ends painted.


Depending on brand name and type of material being used each kind of paint can vary somewhat regarding coverage. With that said, a general guide line is a gallon of paint will cover from 350 to 400 square feet of surface area.

Paints such as elastomeric or stucco block have coverage of 100 to 150 square feet per gallon.

Be sure to read the product label before buying as most labels will tell you how much materials will be needed for the project being done.


The amount of wallpaper you will need depends on the type of paper being used and pattern in the wallpapers design itself.

For the best results calculate square foot measurement of the walls being covered (minus doors and windows) then talk to your local wallpaper supplier.


The link that follows takes you to a site that gives excellent visual descriptions for calculating odd shapes and areas, math about link. Hope you find me again soon.

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