Stabilising Solution: When and How to Use It

One of the essential parts of home decorating is making sure the exterior is fully painted and in pristine condition.

No matter if the exterior walls are made of brickwork, cement, or masonry, it is always important to make sure they are well maintained before applying any paint on top of them.

If the walls are porous or chalky, there is an increased risk of paintwork not adhering to the wall, looking bad once it’s been applied or in the worst-case scenario – starts flaking off a few weeks after you patted yourself on the back for a job well done! In those cases, some extra help is needed, and the so-called stabilising solution is the best kind of help you can get.

A house that has been damaged and needs stabilising solution applied to it before painting.
Demonstration of exterior masonry that will need stabilising solution applied to it.

What Is Stabilising Solution?

Stabilising solution is a primer/sealer with the added quality of binding to chalking or friable surfaces and making them less water-absorbent. It is highly penetrative, meaning it will help fill up any holes in porous surfaces, allowing you to apply a paint system without any issues.

Always remember that applying some sort of exterior primer is one of the most important preparatory steps before applying any sort of paint. It provides both an increased quality and adhesion of paintwork, as well as protection to the wall itself.

When Should You Use Stabilising Solution?

Usually, most masonry walls are primed using a thinned solution of water-based paint, but sometimes that is not enough. Some surfaces need extra treatment to ensure the paintwork is durable.

Friable surfaces are one such example. You can tell a surface is friable by rubbing it with your hand: if it rubs away, then that is a sign it might need stabilising solution.

Some examples of friable surfaces are weathered cement or brickwork, and it is important to check them before applying paint. Without stabilising solution, the crumbling brickwork will cause paint to come off, ultimately ruining your paintwork.

Stabilising solution should also be used when the surface breaks down easily and becomes loose and powdery (also known as chalking). This kind of wall defect is usually caused by weather (specifically wind and excess rain), which is inevitable for most exterior surfaces.

It is recommended to scrape off the powdery surface with a stripping knife first, and then use abrading paper to rub the wall before applying one or two layers of stabilising solution.

It is important to know how to recognise what surfaces would benefit from using stabilising solution on them, because using it when not absolutely necessary can actually be detrimental to the quality of your wall.

Stabilising solution, when not necessary, can cause walls to lose breathability, and keep natural moisture trapped inside. This moisture will come out eventually, causing your paint to bubble or just flake off.

You should also keep in mind the fact that some level of dust/powder on new surfaces is normal. It is recommended to leave the new surface exposed to weather for at least a year before applying any paint or stabilising solution to it.

Unstable masonry can cause defects to your paint system.

How Do You Use Stabilising Solution?

Stabilising solution can be successfully used on many surfaces, including blockwork/brickwork, concrete, masonry and cement.

In order to maximise its benefits on your exterior walls, it is important to keep some things in mind when using stabilising solution. First of all, you should make sure to do a thorough visual examination of the surface you’d like to paint, to see where stabilising solution might/might not be needed.

Before applying the solution, it is best to sand the surface with abrading paper to get rid of excess dust or paint flakes from past paintwork.

You should also make sure you’re applying it during dry weather as moisture in the air can make hamper the effectiveness of the stabiliser.

During application, make sure to use a good brush or roller, and always try to paint from top to bottom for a uniform application.

A couple of coats following a rub down will usually suffice.

Our Top 3 Stabilising Solution Recommendations

Now that you know all the essentials about applying stabilising solution to your exterior walls, there is only one question left: how do you choose the best product for maximum efficiency? We have some top recommendations for you, to make sure your paintwork will last as long as possible in pristine conditions.

The Sandtex Quick Dry Stabilising Solution is definitely a top choice for anyone looking to improve the quality of their old, weathered exterior walls. It is easy to apply with a brush, and it requires 2 layers of solution. It takes 4-6 hours to touch dry, and after 16 hours you should re-coat. The only downside to this product is the volume, as the solution only comes in 2.5l cans.

EverBuild 406 Stabilising Solution is another great choice. Its formula contains a blend of fine polymer emulsion, that penetrates any weathered surface deep enough to seal it. This one comes in 5l cans, meaning you can be sure it will be enough for any purpose you need it for. Unlike other stabilising solutions, this one is suitable both for exterior and interior surfaces, which include materials such as plaster, brickwork and cement.

The Bond-It Stabilising Solution is also a great, ready-to-use product that will make sure to prepare your walls for paintwork. This product is incredibly versatile, as it works on a variety of surfaces including concrete, cement, plaster, plasterboard, renders, pebble dash and MDF. Keep in mind to apply this product only in dry weather, above 5°C.

It’s not just exterior masonry that can benefit from stabilising solution. Fortunately, there are options for interior surfaces too.

Stabilising solution is a great product to use and will increase your walls’ durability whilst preparing them for future paintwork.

No matter how old and weathered your walls are, they can be brought back to life with a little bit of help, and stabilising solution is just the right tool for it.

Your Questions, Answered

Our readers ask plenty of questions about stabilising solutions so as well as providing them with this article, here are some direct answers to your questions.

I’m looking to paint internal soft red brickwork. It’s highly absorbent and I’m going to be using water-based paint to match the rest of the room. Do I need to use a stabilising solution?

If it’s highly absorbent then you might want to use a stabilising solution but personally, assuming the brickwork is in sound condition, I would use either Zinsser Guardz or simply use a mist coat.

I’ll be painting a new build exterior soon. Does it need a sealer or stabiliser?

New builds don’t generally need stabilising. My advice would be to go for a mist coat and top coats. FYI, if you’re looking for good exterior masonry paint, I’d recommend Sandtex (the smooth version rather than textured). Here’s an exterior I painted recently using their white masonry paint:

Does pebbledash need to be stabilised before applying masonry paint?

Pebbledash isn’t a porous surface so you don’t need to stabilise it, especially if it’s new. For new pebbledash, treat it like you would fresh plaster: 1 mist coat followed by 2 top coats.

I’ve just had my bungalow rendered and was wondering whether I need to stabilise it or not?

Along with using on chalky or dusty surfaces, stabiliser can also be used on surfaces with high absorption. Some render can be highly absorbent and slightly friable due to the type of sand and mix. So it’s the same as sealing a porous wall.

I personally wouldn’t use it unless the sand was really loose or the render is brittle. I do know lots of painters that do use it for these reasons on new render – almost like a mist coat and also for some other reasons. But I believe this can affect the coverage.

Bear in mind that the walls would also need to be fully dry and subsequent coatings would take a lot longer to dry.

My new house was painted with masonry paint 6 months ago but now the paint is coming off in chunks. What can I do?

Whilst you may be eager to repaint the areas where the paint is coming off, chances are, there’s more to come. My advice would be to wait a few months and reassess. At least then the process of removing the paint will be much easier. At that point you’ll want to rub down the entire surface, use a stabiliser and then paint as normal.

Unfortunately, it sounds like whoever painted your home didn’t use stabiliser in the first place.

Have you ever encountered lime paint on a ceiling? I’ve tried to roll the ceiling and it’s just pulling off in strips. Will a stabilising solution help?

Removing it is the only way to ensure a bond. Stabilisers, sealers etc over the top of it won’t do anything to improve on what little adhesion it has to the substrate. I’ve seen gypsum plaster over skims that have failed because of this despite being PVA primed.