Cleaning Walls Before Painting: Your Easy Step By Step Guide

Like with any task, preparation is key. Without meaning to sound like a walking cliché, failing to prepare is preparing to fail. So why would you not ensure your canvas is in perfect condition before starting your project?

Your walls are the focal point of every room, and you don’t want to waste your time, effort and money to end up with shoddy results. But preparing your walls for painting is easier and less pain-staking than you think!

cleaning walls before painting

So here it is, an easy and stress-free step by step guide to cleaning your walls before painting.

The first thing you need to do is check the condition of your walls. Depending on their condition, not all the walls in your home may need pre-treatment, but I would always advise you thoroughly check beforehand. The tests to check your walls are very simple and will save you endless amounts of time in the long run.

Test one: Wipe down your walls with a clean, dry, white cloth. Cover the whole length of the wall and make sure you don’t miss any parts. If the cloth doesn’t change color or becomes a light gray, this means that the wall does not need a wash on it before painting.

If the color change is more severe, then you will need to clean the wall properly to ensure optimum results.

Test two: Next you need to determine whether you need to use the TSP or not. TSP, otherwise known as Trisodium Phosphate, is a powder which is used to cut through oil, grease, and other similar stains.  Being an alkaline with a pH of 12 means that it can easily tackle otherwise difficult stains to leave you with a clean canvas to start your painting project.

Professional decorators will usually opt to use this cleaning solution as it has proven results and it is also easily accessible. One excellent TSP product on the market is Savogran 10622 Trisodium Phosphate (TSP) 4.5lbs.

This product boasts that it can remove normal every-day stains from your wall but also the more difficult stains such as smoke, soot stains, and mildew stains if mixed with bleach.

The solution does not leave any residue and it doesn’t have an odor so your house will not be reeking of strong chemicals.

You simply mix the required amount of powder with hot water (this will prevent the solution from clumping) and you are ready to go!

One thing to note is that you need to be careful how you store it when it’s not in use.

If you keep the powder in its packaging in a moist room, such as the bathroom or laundry room, it can start to clump as it is reacting to the moisture in the air.

My advice would be to keep it in a sealed plastic container so the product will last you much longer.

To TSP or To Not TSP, That is the Question

As mentioned previously, not all the walls in your house will need vigorous cleaning.  However, there are certain rooms that will get the extra WOW factor from a bit of TSP cleaning.

The kitchen

Kitchens are notoriously one of the worst rooms for painting. The everyday grease and grime build up can leave a blotchy finish to your walls if you just try and paint over them. Because it is a strong alkaline, TSP is perfect for removing these stains with ease to provide the best results when painted.

The bathroom

Soap scum and lime scale build-up is a nightmare in bathrooms especially. Similar to kitchens, the bathroom graces us with a plethora of difficult stains to remove so you want to make the process as pain-free as possible.

Children’s rooms

Children have a habit of leaving you beautiful portraits on their bedroom walls. And unfortunately, you cannot always be sure what art supplies they will use to create their beautiful masterpiece. Although it can be thoroughly annoying, knowing that you can easily remove such stains will remove some of the pressure.

High footfall areas

As a side note, TSP can also be used as a normal cleaning solution. Things such as door handles are touched countless times throughout the day.  Cleaning with TSP will help remove some of the bacteria that comes with constant human contact.

If using TSP doesn’t really sound like your thing, then you can still clean your walls prior to painting with excellent results.

However, there is still a list of DO’s that need to be taken care of before you start your wall rejuvenation.

  • Say goodbye to dust bunnies! Yes, it’s tedious but it is a necessary evil. You need to make sure that all cobwebs etc. are removed before you start painting so you don’t end up just painting them onto the wall.
  • You want your walls to look exceptional from top to bottom, and at this stage, you need to start at the bottom. Baseboards and trims are regularly forgotten about and end up looking drab when the painting is complete. Just a simple clean down with a cloth will remove any dust or cobwebs and will ensure a better finish.
  • Bobbly walls are not the best for painting, so you need to make sure you have a smooth and clean starting point. Use sandpaper to even out the texture of the surface and remove any dirt from the wall.  It is more a laborious task than using the TSP, but the end results will be the same.


Now down to the nitty-gritty, literally. If you are not using TSP, hot soapy water is the other alternative.

Not a lot to it really, just grab a cloth and start washing. As mentioned previously, rooms such as the kitchen will have much tougher stains to deal with and you need to make sure that they are totally removed.

Wiping over the wall with just hot water after using the hot soapy water will ensure that there is not any left-over residue on the wall. To wash wooden panels or other similar surfaces, the process is pretty much the same.

These surfaces require less rigorous scrubbing as you don’t want to damage them with too much scrubbing; you just need to ensure they are free from any dust or cobwebs as any debris will transfer onto your newly painted walls.

To wash your little Picasso’s creative scribblings off the wall, you need to use liquid soap as it is more adept at dealing with these sort of stains. You need to apply the liquid soap directly to the stain and then use a wet cloth to clean the wall. If it doesn’t work the first time, you will need to repeat the process until the stain has gone.

Depending on the extent of the stain, this can be quite frustrating and time-consuming but unfortunately, it is a necessary evil that needs addressing. To wash glossy areas, it’s time to bring the sandpaper back out. Rub the thick or glossy areas of the wall with the sandpaper and then wipe with a clean cloth to remove any of the remaining sanding dust.


cleaning walls before painting

It’s time to get your glasses on and examine your walls thoroughly. You need to find any flaws or cracks in your walls and gently press the spackling into any of the defects, preferably using a putty knife.

After filling in the cracks, you need to try and smoothen it out so there are no inconsistencies.

Window and door trims are dealt with in the same manner, but I would advise using your finger instead to ensure that it dries smoothly.

One thing to note is that you need to make sure that the spackling is fully dry before you try painting over it, otherwise the paint will either suck the spackling out of the crevice or it will leave an uneven finish.


And that’s it ladies and gents. Whether you’ve decided to use TSP or not, by this stage you should have stunning, smooth and clean walls ready to let your creative ambitions conquer any wall.

The state of your walls can make or break your decorating endeavor, so you need to make sure you invest enough time to ensure that it is done properly. And when you think of it, using this step-by-step guide is a small price to pay for a beautiful home.

So, push your sleeves up, get your vacuum cleaner ready and prepare to be mesmerized by how simply you can create the perfect canvas for your home transformation.

Categorised in:

Comments are closed here. Protection Status