Preparing for decorating

For most people a new home means new look décor but there is a lot to consider before you don your painting togs and load up the roller. Our guide should leave you feeling like a pro whether you're painting or wallpapering.


Prep for the prep

It's easy to underestimate how much preparation you may have to do before your walls are ready to be painted. To get the best finish and the longest wear from your redecoration, bumps, nicks and cracks will all need to be filled and sanded back. No quality of paint will give a bad surface a good finish.


Depending on the age of your home and what the walls have been exposed to, you may want to consider washing the walls with a specially formulated soap. Sugar soap is the most common and will remove most residues from cigarette discolouration to stubborn dirty marks. Gloss paint especially needs to be washed with sugar soap and you'll get a better finish if you 'score' the old gloss with some light sandpaper. This just means scratching the surface of the old gloss paint with some sandpaper. This will give the slippery gloss paint something to cling to and ensure you get less drip in your finish, especially if you're inclined to paint it on thick.


Primer is essential when painting a new dry wall but if you're covering a dark colour, without a primer this will be a much bigger job than redecorating with a similar colour and could take several coats of paint. You'll benefit from using a primer as it acts as a blocker meaning fewer coats to cover any colour underneath it. Ideally it should give you one-coat coverage and it provides a good surface for the end paint colour to adhere to, giving you a much better result. You might want to even consider tinting the primer. This method is where you introduce some of the end colour to the primer so that you'll already be a lot closer to the final colour once the primer is applied and dry. Dust, smoke and age old dirt can cling to walls and ceilings even after sugar soap washing so if you're in an older home, consider that your walls could have seen a lot more than you know about. Water based paint can actually draw out nasties under the old paint, so a primer is a great idea if you find that your wall isn't doing quite what you expected due to the old paint underneath.


You should also anticipate using twice as much masking tape as you might expect. Depending on the area you're decorating, you could have to mask doorframes, light switches and plug sockets. If you're doing glosswork like skirting boards and doors; masking the floors, walls and window glass surrounding the area to be glossed is essential for a good finish. It will also save you hours later as you can simply whip the tape off for a clean finish rather than having to work to remove gloss paint from floors and windows after the fact. Remedy is better than cure here.


Dropcloths! If you've never painted a room before you may well underestimate the amount of splatter you can produce in a few turns of the roller. You'll need something durable to protect any furniture left in the room while you're painting. Canvas cloths are best as they absorb any dropped paint rather than plastic cloths which leave the paint sitting on top of them and can grow slippery, depending on how much paint ends up on them. Canvas covers should last you for several cycles of painting while plastic will likely need to be thrown out after one room so they're more economical too.

How much paint will you need?

There are a lot of online calculators out there for calculating your square footage but it's fairly straight forward maths.

You'll need the length of each wall and the height to begin calculating your wall surface area. You can deduct the surface area for windows and doors if you want to but most DIY stores have refund policies if you have a lot of unopened paint left. You should check the return policy at your chosen DIY store in advance of purchasing to be sure of their individual terms. You'll only need one wall height unless your room is really tilted, in which case you should do this calculation on each wall and square the totals separately.

  • Add the length of each wall together
  • Multiply the sum of the length by the wall height to get the total wall area
  • Divide the total wall area by the paint coverage sum of the m2/L number on the paint tin.

Dulux offer a good guide to calculating your square footage.

Colour me happy

It's a great idea to get testers to get a good feel for the colour in your home versus the colour chart. The light in the room you're decorating could change the look of the colour to you, it may be darker or lighter than you expected. It's not worth getting halfway across a wall only to decide you don't quite like the shade.

Put as many coats as you were planning on using on your entire wall on in thin layers across a sample area to see how it dries but beware of brushstrokes and drips on the floor! The brushes in sample pots are generally thick and could leave you with a brush stroked sample patch ruining your end finish. Surely we don't need to explain the drips caution!

Have a think about where you paint dark colour samples. Are you intending to have a light colour on that wall you've just painted a purple sample onto to the middle of? Get ready for putting down several coats to get it covered.

Getting started and keeping going

Finally ready to paint? Here are a few tips to make that easier too:

You've got your roller and paint tray all ready, but first grab that paintbrush. Cutting in is simply where you use a brush to paint a light layer of paint on the right angles of the wall before you take a roller to the rest of the area. This generally means that your edges will be tidier and give a better finish. When painting, it's best to paint broadly in a W pattern which minimises roller marks and creates better coverage.

Done for the day and painting tomorrow? There are a number of tips out there about protecting your paint and paint laden brushes to avoid having to wash them out every night, the best one we've tried and tested has been cling film. Wrap brushes and rollers individually in cling film, making sure that the cling film is tight, you need to ensure that as little air as possible can reach the paint to avoid hardening. You could even wrap cling film over the paint tray itself. Just unwrap the next day and you're good to go.

If you're using similar shades in different rooms, make sure you know which shade is being used where. This is especially important where you are using paint trays where you could easily confuse the shade.


While not as big a trend as it has been in previous years, wallpaper is still a great way to get finishes and designs that you could not get with paint. Much of the same prep work as we've mentioned above is still necessary as the wallpaper needs a sound surface to be stuck to with one exception. Where you will reuse fixings such as book shelf brackets or intend to hang a picture from the same place it's not worth filling these holes. When you come to hanging the wallpaper, use toothpicks or matchsticks to identify the holes underneath the paper to help you find the original hole for the fixings.

Essential tips

  • Work from the right (or left if you're left handed) of the window. Working away from the window means that you'll have fewer issues with shadow if the edges overlap slightly.
  • Does your wallpaper have a large pattern or overwhelming motif? Hang the first strip in the middle of the focal point, above the fireplace, for example, if you're doing a feature wall, and work away from this point until the area or wall is completed. This will ensure that your pattern is central and symmetrical within the eyeline of the paper.
  • When picking your paper, make sure that all of the rolls are from the same batch. You'll see a serial number on each roll, this should match for each roll that you buy. Most patterns vary only slightly but you don't want to find out how different the pattern or colour is halfway through the room.
  • When hanging paper over paint, check that there is no flaking paint on the area you want to paper. This will lead to the paper falling from the wall later if the surface below it continues to degrade as the paper will simply have nothing to cling to.

And you're done. Pack up your canvas sheets and your painting togs and enjoy your new room.

Tempting as it will no doubt be to bin everything including the brushes when you're finished, it is worth cleaning - with water or white spirit depending on the paint - and keeping your brushes and rollers. Once you see how good your room looks when you're done, you're bound to have a hundred flashes of inspiration for the other rooms in your house but at least now you know just how much prep there will be.

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