Exterior Paint Still Sticky? Here's Why And How To Fix It

Exterior paint can remain sticky due to several factors, including temperature, humidity, paint quality, and the number of coats applied. Painting in cold temperatures, high humidity, or applying too many coats of paint can all contribute to the paint not drying properly and remaining sticky. Additionally, using low-quality paint or not allowing sufficient drying time between coats can also result in sticky paint. To avoid this issue, it is recommended to paint during mild temperatures, low humidity, and to follow the manufacturer's instructions for drying times and coat application.

Paint was applied too thickly

If your exterior paint is still sticky, it could be because it was applied too thickly. This phenomenon is called "blocking", and it occurs when you paint thick layers over each other without giving the previous layer time to dry.

When you apply paint too thickly, you are essentially blocking the paint from drying by covering it with another coat. A small dry layer forms on the outside edge, but the paint underneath is still wet. Depending on the severity of the blocking, you might be able to wait it out—allowing the paint to dry over several months. However, you may need to start over.

To prevent this issue, it is important to wait for each coat of paint to dry thoroughly before applying the next one. It is also a good idea to use thin layers of paint and build them up gradually. This will help ensure that each layer dries properly before you add the next one.

Additionally, using a primer can help prevent blocking. Primer neutralises the wall colour, leading to less layered paint. This helps the overall paint job dry faster. However, it is important to make sure that the primer you choose is compatible with your paint.

Other factors that can contribute to paint not drying properly include high humidity, extreme temperatures, and low-quality paint.

Poor ventilation

Ventilation plays a crucial role in paint drying because it helps regulate temperature and humidity levels, both of which are critical factors in the drying process. In an enclosed, poorly ventilated space, the temperature can become too high or too low, hindering the paint's ability to cure properly. Additionally, poor ventilation can lead to increased humidity, causing the paint to remain tacky.

To avoid issues with sticky paint due to poor ventilation, it is recommended to paint in a well-ventilated area. Open windows and doors to promote airflow, or use fans to circulate the air. If possible, paint during mild temperatures when it is not too hot or cold, as extreme temperatures can impact the drying process.

Additionally, it is important to allow sufficient time for each coat of paint to dry before applying the next one. This gives the paint adequate time to cure and reduces the likelihood of tackiness.

By ensuring proper ventilation and allowing adequate drying time, you can help prevent your exterior paint from becoming sticky and achieve a smooth, even finish.

High humidity

The humidity where you are painting should ideally be between 40 and 70 per cent. Every type of paint might require a slightly different humidity. Check the paint container for the proper humidity level, as this should be listed.

Low-quality primer

One of the most common reasons for sticky paint is the use of a low-quality primer. A primer is used to neutralise the wall colour and reduce the number of coats of paint required. However, if the wrong primer is used, it can cause the paint to become sticky and slow-drying.

It is important to research and find a primer that is compatible with your choice of paint. This will help the paint to dry faster and reduce the chances of stickiness. A high-quality primer will also help the paint to stick to the surface better, resulting in a more durable finish.

Additionally, it is crucial to prepare the painting surface properly. The wall should be clean, dry, and free of any dirt, dust, or grime. If there are any cracks or imperfections, they should be patched up before painting.

By using a suitable high-quality primer and adequately preparing the surface, you can avoid the problem of sticky paint and achieve a smoother and more durable finish.

Incompatible primer and paint

Paint not adhering to primer can be frustrating and can ruin your entire paint job. One of the reasons for this issue is the use of incompatible primer and paint.

Paint is a coloured liquid used to coat surfaces for protection, decoration, and durability. Primer, on the other hand, is a preparatory coating that is applied before painting to create a smooth and even surface for the paint to adhere to. A good primer acts as a bond between the surface and the paint, ensuring that the paint sticks to the surface and does not peel off.

Using incompatible primer and paint can cause poor adhesion. For example, if you are using a water-based primer, you should use a water-based paint. Similarly, if you are using an oil-based primer, you will need an oil-based paint. Latex paints, for instance, are known to have poor adhesion to oil-based paint.

To avoid this issue, it is important to choose a primer that is compatible with the type of paint you are using. Additionally, proper surface preparation is crucial. Before priming, ensure that the surface is clean and free of any dirt, grease, or imperfections, as these can prevent the primer from adhering properly.

By using compatible products and properly preparing the surface, you can achieve a smooth and durable paint finish.

Frequently asked questions