Painting your houses external facing bricks is an instant way to increase curb appeal. With such a renovation, it is important that the risks are minimised by doing your research before commencing such a task. Otherwise you risk an expensive, potentially irreversible nightmare. Promain‘s technical team would like to give our customers an initial guide to help you decide how to proceed when it comes to how to paint fletton bricks.
Although there are many types of engineering bricks, this guide is aimed at fletton bricks only. If you are looking at painting a different type of brick, it is best to call our technical team to discuss your individual needs.
How To Identify Fletton Bricks
Fletton bricks are the construction industry’s common workhorse engineering brick. They are identified as very hard and dense, with a pinky, patchy colour.
The face of the brick tends to have a texture where bricks rest against each other in the kiln. Flettons can be dense and shiny and cause poor adhesion to some paints.
Flettons have been used throughout the UK as a staple since the start of the 20th century.
The Problems Involved With Fletton Bricks
There are a number of issues when it comes to painting any type of facing brick. Below are the most common issues.
The presence of kiss marks, dark, smooth and sometimes slightly glazed areas on fletton bricks can result in paint failures in a short number of years. In addition, a tendency to form powdery surface deposits of efflorescence can also cause subsequent failure. Efflorescence is the migration of salts to the surface of a porous material.
Another issue with painting fletton bricks is a tendency to fail extensively due to the effects of trapped moisture. This moisture will push any coating off the surface over time.
Fletton bricks can also suffer from breathability issues. Depending on the age of the house, without a damp proof course or cavity, any painted external brickwork would need to be breathable. Modern houses built after the 1970’s generally have a damp proof course. Any buildings prior to this would need the construction style checked prior to coating.
Suitable Paint For Fletton Bricks
When it comes to painting your house, it is vital to not use a cheap, low quality paint coating. If you do so, you risk the paint having a short lifespan and flaking or peeling occurring. We always recommend using a product with good reputation from a manufacturer that understands the chemistry and requirements without compromising on cost. Before choosing a system, we suggest calling our technical team to discuss the project.
Promain’s Suggested Primers:
- Rust-Oleum Pegalink Universal Adhesion Primer – Aids adhesion on smooth surfaces
- Zinsser Bulls Eye 1-2-3 Primer Sealer – Prevents water satins, graffiti and grease spots
- Mapei Silancolor Primer – Regulates the absorption of the substrate before applying Silancolor Paint.
Promain’s Suggested Finishing Coats:
- Rust-Oleum Paracem – Available in Satin Matt and Semi Gloss finishes
- Zinsser AllCoat Exterior – Available in Satin or Gloss
- Mapei Silancolor Masonry Paint – Available in a vast range of colours from the ColorMap system
- Glixtone AC1 – Smooth finish with a slight sheen. Tintable to over 200 pastel colours
- Keim Soldalit ME – Mineral matt finish. Does not require a primer
As standard we recommend not mixing brands when specifying a combination of products in a job. This way, if any issue arises, they can be resolved painlessly. It is recommended to thoroughly read data sheets prior to application. Always ensure the weather is suitable – don’t just start a job without proper understanding of the timescales involved.
For further information in regards suitable conditions, view our article here:
What Are The Ideal Weather Conditions For Painting?
How To Paint Fletton Bricks
1. Surface Preparation
Areas to be painted must be clean, dry and free from any grease, oils or contaminants that would interfere with the adhesion of the paint. Remove any loose material by scraping or brushing with a stiff bristle brush to leave a sound edge. Prior to painting, the moisture content of the bricks should not exceed 18%. To test for this, you can use a standard moisture meter.
Promain recommend the removal of all visible signs of organic growth with an anti fungicidal agent such as Centrecoat GS36 Fungicidal Wash. You should allow the GS36 to dry without rinsing. This allows your brickwork to continue to be protected as time goes by.
Rake out and re-point any unstable brickwork by pointing with a suitable cement mix in accordance with the manufacturer’s instructions. Allow to cure.
We recommend priming the full face to be painted with one of the above primers. Ensure to follow the manufacturer’s instructions. Ensure the weather is suitable for the longest time possible. We suggest a dry day without chance of rain with little wind.
Decorate with your chosen topcoat using the appropriate tools and quantity of coats as per the manufacturers data sheet.
Do you require further advice when chosen an appropriate system for coating your external fletton bricks? Contact our technical team today on 01462 421333 for further information today.