Buy the Right Amount of Paint to Reduce Waste

If you're looking to refresh your home or tackle a redecorating project a fresh coat of paint is a quick, easy solution that can be done in a weekend. A common mistake DIYers make is to buy more paint than what is needed for the job. Not only does this end up costing you more money but it can have some pretty heavy consequences on the environment too.

How much paint do you really need?

Let's do the math

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According to a leftover paint research study, the average household has 6 cans left over for touch-ups and repairs - but actually 30% of the respondents have accidentally purchased too much of it. This adds up to what is to be estimated a total wastage of 50 million litres with only less than a million of it actually being recycled reported in this resource efficiency action plan for decorative paint.

Along with being a waste of money, paint waste is very hazardous to the environment due to the solvents and toxic heavy metals which are bad news for the soil, water and surrounding wildlife.

Whilst you think it might be good to save for those repairs in your garage or cellar, an open can will only last for a couple of years. So that's why it's important to carefully calculate with this paint calculator. Then if you do happen to have just that little bit too much, you can recycle at Paintcare or Community RePaint.

Measure up

Firstly you need to get the measurements of the room, including the width of the walls, the height of the floor to the ceiling. Alternatively, just pick the rough room size (small, medium, large, extra-large) and you’re halfway there to figuring out how much paint you need. From here, you'll want to measure windows, doors, or any other relevant spaces that will not need any paint, and subtract that from your square footage total. Or again, the calculator does this all for you!

Consider colour changes

If you are repainting or shifting to a colour that is similar to the existing paint, fewer coats will be required than a shift to a drastically different colour, e.g. moving from light to dark. More significant changes will require more coats, so this is an essential factor to keep in mind. Another variable can be a textured surface which will likely require more paint than a smooth one. The texture increases the surface area by nearly fifty per cent.

Different paint finishes

Coverage can also be affected by the type of paint you purchase in terms of sheen level. As it decreases, the coverage increases. Semi-gloss and glossy paints will require more coats of paint when compared with something a little flatter.

Remember the primer

Finally, consider the use of a primer. Surfaces like drywall, plaster, and wood that have not been primed will absorb more paint than something that has been primed. Higher absorption means more coats of paint. Primer means better adhesion, but it also fills in small holes which would otherwise be filled with paint. So after using the paint calculator and then factoring the few additional variables, you should be pretty close to working out the right amount needed. This will save leftovers, money and most importantly, the environment!