In Ceilings, Drywall, Exterior House Painting, How To, Interior House Painting, Paint FAQ's, Painters Advice, Painting FAQ's, Painting Tips, Renovations

Plans have been made for getting a whole new look to your space.  Whether you have decided to paint one room or you are going to be painting every room, you are going to want to know how much paint you will need to get the best end result.  Even before you have picked out the final paint colour you are going to want to get an idea on how much paint to buy.

We will share a few tips to help you with the estimating on how much paint you will need to be able to paint at minimum 2 coats of finish paint colour.

calculator for estimating how much paint you will need when before painting

How To Estimate How Much Paint You Will Need to Buy

To estimate how much paint you will need to cover the walls of a room, add together the length of the walls, multiply that number by the height.  This number is the square footage of the room.

A small room that measures 10 x 10 equals which can be a small bedroom or bathroom will need 1 gallon of paint as on average most paints will cover 400 sq ft.  You will have left over paint but you can save left over paint for touch-ups or make sure to dispose of it properly.   The City of Ottawa offers designated dates each year to dispose of all hazardous waste.

Make sure to read the product label as every paint manufacturer formulates the paint products differently.  Although the variance is very small between brands, checking that label will just confirm that you are getting the best paint product for your painting project.

Newly installed drywall will soak up more paint, therefore it is recommended to use a paint primer first.   Approximate additional paint you may need is 1 gallon of paint primer, depending on the type of paint primer used.

How To Calculate Size of Room To Know How Much Paint You Need To Buy

If we take the average home in Ottawa and use the measurements of a regular sized bedroom we will be able to calculate how much paint needs to be bought.

Let’s just say for this example we have a room that measures 12′ x 14′ and has an 8′ ceiling.  Multiply the width by the height of each wall and then add them all together.  That all adds up to 416 square feet.  Painting with a high quality (premium) paint product  will provide good coverage with 2 coats of paint finish.  If you are painting over damaged surfaces with drywall repairs and patching or if you are repainting a lighter colour over a darker paint colour you may need to apply three to four coats of final paint colour.  The deeper the colour that needs to be painted over the more paint coats will need to be painted.


Keep in mind that the amount of paint you will need will vary for your individual project.  If you are unsure about the measurements and calculating how much paint you will need, we recommend you book an appointment for a painting estimate with a painter in Ottawa.

If you are doing a DIY painting and tackling the project on your own you may find these house painting tips helpful.  The following websites offer calculators to help you estimate the square footage of the room along with how much paint you will need.  Here are the links to some of the major brands, note that by clicking on the link you will be taken to the individual paint manufacturers website.   Benjamin Moore Paints PPG Paints Pratt & Lambert Paints Sico Paints & Stains

As frustrating as it can be to have to make another trip back to the paint store because you have underestimated the amount of paint you needed, it better to underestimate than to go over, as once you have had the paint colour added and you have bought the paint it is non refundable.  Best to go back and buy extra than to have extra cans left over.

Tips For Your Next House Painting Project

Some considerations to keep in mind the next time you are planning to get started with painting any room is to prepare all you will need before getting started.  After the calculations have been made and the paint is bought you will want to consider things like the right paint colour, choosing the perfect shade,  the best paint finish for the individual room, the right paint brush and paint roller and other tools needed as well as you may also find these house painting tips useful to use as a guide.

A Painters Tips for Estimating How Much Paint You Will Need

Start with less paint then you think you need, it’s easier and cheaper to go back to the paint store and buy more as opposed to having left over cans of paint that are non-refundable.  If painting a light paint colour over a dark paint colour it will take at minimum 2 coats of finish paint over the primer and sometimes even 3 coats are will be necessary, depending on how deep the dark colour to be painted over is.  If you use a primer that is tinted close to the paint colour  then it may save you from painting that 3rd coat.

Remember these are only guidelines and suggestions, they are not guaranteed results.  If you want to take the pain out of painting then we recommend you hire the services of a to relieve the burden and the stress of figuring it all out.

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This post was originally published on Jun 4, 2017 at 07:00 and edited Feb 02, 2020 at 13:25