Tar paint – apply with an airless sprayer

#tar paint

Natural bitumen has been used, tried and tested for thousands of years and is known for its waterproofing and adhesive qualities.

This material is found in deposits such as oil sands, while refined bitumen is obtained as a residue from the distillation of crude oil.

Tar-based paints and coatings are popular in many industries and in the recreational sector.

In this article we will look at the characteristics of tar paint and how to properly spray bitumen with an airless sprayer. As an introduction to this topic, the video below shows the simplified application of tar with a Graco pump.

Tar paint

This material is suitable for many different applications due to its weathering properties, corrosion resistance and adhesiveness.

It is primarily used as a protective coating for buildings, iron, steel, concrete, masonry and wood structures.

It is generally considered an economical option and can be used both above and below water or ground.

Advantages and disadvantages of tar paint

It is generally less expensive than many other coatings offering similar waterproofing performance. It can also be applied to many types of surfaces.

Here are its main positive points:

• Anti-corrosive
• Weather resistant
• Odorless (once dry)
• Fast drying
• Good adhesive properties
• Fairly durable

That said, tar paint is not always the most attractive option depending on the desired application. It is also usually only available in black and can be difficult to apply in very cold conditions.

It will bleed through some topcoats, limiting its use on some substrates. Finally, although it is generally quite stable to heat and UV, its shelf life can be shortened in extremely hot and sunny countries.

For which jobs should I use tar paint?

Versatile, it can be used on ferrous and non-ferrous metals as well as concrete, wood and masonry. It is frequently used on metal gutters, fire escapes, ladders, railings and fences. In the marine industry, bitumen paints are commonly used on boat hulls.

Most people associate bitumen with roofing and it is of course commonly used as a weather resistant coating for flat roofs, felt roofs and industrial roofs. It is ideal for this purpose because it dries quickly, which is a great advantage in some countries.

Bitumen is sometimes used to waterproof underground masonry and concrete foundations. Because it is resistant to contaminants and has no odor, the coating is also suitable for water tanks (other than drinking water) and other similar applications.

Is bituminous paint toxic to plants?

Once the tar paint is completely dry, it would be non-toxic to plants, making it suitable for use inside wooden planters.

Similarly, tar paint can be applied to wooden posts that are to be buried in the ground, as long as it is allowed to dry completely before it comes in contact with the soil.

Application of a tar paint with an airless

Considering the viscosity and the relative difficulty of applying a tar paint with a brush, this material has everything to gain by being applied mechanically.

In this case, a very powerful machine will be needed to pump and spray this material without hindrance.

In our article Which nozzle should I use to spray bitumen?, we have summarized all the steps involved in spraying bitumen paint with the best Graco and Wagner airless pump.

What precautions should be taken when applying bituminous paint?

There are a number of points to know and respect to work safely with this material:

• Protect skin and eyes and apply in well-ventilated areas outdoors
• Do not inhale
• Do not apply near open flames, sparks, heat sources or hot surfaces
• Dispose of waste responsibly as it is toxic to wildlife
• Do not swallow

Beforehand, you will need to prepare the surface thoroughly by removing dust, oil, grease, old coatings and surface contaminants.

A primer is not usually necessary with bitumen paint, but occasionally, for extra protection of bare metal surfaces, apply a zinc-rich primer or a metal primer.

Best results are obtained in warm (minimum 10°C) and dry conditions.

Finally, be aware that cleaning your equipment is critical when using tar paint. To learn how to properly clean the tar from your airless pump, watch the video below.