Dulux Trade Blockfiller Plus

A water-based product formulated for filling voids and imperfections in breeze block walls.

Anyone who’s painted a concrete block wall will already know that they absorb a lot of paint and it can be difficult to get a decent finish. By using Blockfiller as a first coat you can eliminate these problems.

The traditional way of painting blockwork, internally, is with a contract matt emulsion. Thinned significantly, in order to reduce the porosity of the blocks, and often taking 3 or 4 coats to get anything like an acceptable finish.

One way around this problem is to use a cement slurry to fill the small holes in the block surface but this requires care to get the right mix of sand/cement. It can also be difficult to get a smooth and even finish this way.

Blockfiller Plus is specially formulated for sealing concrete blocks and you can achieve a good finish with ease. And, although it is quite expensive, you will save a significant amount of time and money as you may only need one subsequent coat, 2 at most (depending on colour).

Blockfiller Plus has a high solid content of 43%, almost double that of ordinary matt emulsion. Blockfiller can be applied by airless spray, brush or roller.

You should stir thoroughly before use and do not add water otherwise you will be losing the filling properties.

When using a brush, It is advisable to finish with a roller in order to remove brush marks and to achieve a smooth finish. Once dried you can finish with a regular paint of your choice.

Can Blockfiller be used Externally? READ MORE…

No, Blockfiller is for interior use only. For exterior walls you should use a masonry paint – although, for breeze block walls, there is no need to use a premium brand.

You will need to thin the first coat so it soaks below the surface and then use two more coats as a finish – possibly thinning the second coat slightly to aid application.

Is Blockfiller Microporous? READ MORE…

Blockfiller is formulated to tolerate normal levels of atmospheric moisture within interior environments but isn’t breathable as such – and is not recommended for use where damp ingress is possible – such as single-skin walls subject to weathering on the exterior face.

In such cases it is advisable to use a standard Contract Matt Emulsion internally and an exterior masonry paint on the outside surface.

What Paints can be used as a Finish? READ MORE…

Almost all interior paint systems can be used as a finishing coat. Blockfiller can also be left as a finish in itself.

Are there any Alternatives to Blockfiller? READ MORE…

In the UK, the main alternative product is Bedec Blockfill, which is very similar.

Where else can I use Blockfiller Plus? READ MORE…

It can also be used on rough finish concrete walls, brickwork and ceiling tiles.

See Also
Painting a wall with a roller
Painting Rendered Walls
A terrace of houses all painted a different colour
Exterior Masonry Paints