What is a joint?
Masonry mortar is used in classic masonry. Open joints of about 10 to 15 mm wide are formed between the bricks. At the end of the working day about 15 to 20 mm of this masonry mortar is scraped out, which creates the necessary space for filling up the facade with a joint mortar.
A joint mortar has 2 important purposes:
- A practical purpose: the open joints are filled correctly and efficiently.
- An aesthetical purpose: 10 to 20% of the visible wall surface consists of the joints and therefore the joints greatly influence the appearance of the finished facade.
A joint mortar mainly consists of cement, sand, and water. The composition of the joint mortar varies depending on the colour of the joint mortar. Sometimes lime and mineral colouring agents are added.
The actual jointing can vary depending on the region and the building culture. There is no golden rule.
- Difference in timing
In Belgium, usually the rough structure is finished first while jointing is done in a later phase. In the Netherlands, jointing is done from the bottom upwards so that laying bricks and jointing are practically done simultaneously. Every system has its advantages and disadvantages with regard to planning, moisture effect, consistency of the joint colour, speed, scaffolds, etc.
- Difference in material
You can use a jointer for jointing. A long jointer is used for the horizontal joints and a shorter jointer for the header joints. Jointing can also be done using the spraying technique.
Some tips for a beautiful and high-quality result.
- Always use clean water for making the joint mortar.
- In case of warm and dry weather conditions make sure that the fresh jointing does not dry up to fast. Bad bonding between the facing brick and the joint mortar can cause the joint mortar to fall out or pulverise in time. Avoid this by misting the facade with clean water during the first few nights after jointing. This way the joint mortar can stiffen naturally.
- According to the Belgian standard we advise you to create a joint of which the depth isn’t smaller than the height, with a minimum of 10mm.