In order for garden paths or paved driveways and house entrances to be stable, a joint filling is necessary. Unfilled gaps make the surface appear unfinished. There are different materials that differ in price and offer different advantages.
Paving joints can be tightly sealed or filled with permeable materials
Joint filling materials:
- joint sand: cheap and easy to work with
- quartz sand: beautiful appearance and easy processing
- rock flour: good stability and dry filling
- grout: optimal sealing
joint sand
Sand has a coarse-grained structure and encourages rainwater to seep away. Lime or crushed sand are recommendable and inexpensive products. They are processed when wet so that the particles can seep into the gaps and solidify better. Joint sand has the disadvantage that wild herbs appear over time. Due to the low supporting properties, the filling material is suitable for large areas that will be covered with cobblestones.
quartz sand
This sand offers the advantage that you can keep the joints small. The grain size promotes good infiltration when grouting, which means that the laid stones are more stable. The substrate is often used because of the white appearance. However, it tends to get dirty and cleaning is difficult. Weed growth should not be underestimated.
rock flour
This filling material is also known as basalt flour and has a dark appearance. It has similar properties to quartz sand (15.85€) but the support is higher. In contrast to sand, the rock flour (14.13€) is not filled in wet. To minimize the risk of clumping, you should sweep the substrate dry. The disadvantage is a higher price.
grout
This material is the most expensive filling. To avoid weed growth, you should use a synthetic resin-based paving joint mortar. Such a product seals the surface so that weed seeds cannot penetrate with their roots. The joints are easy to clean because the filling is not swollen. Joint mortar proves to be disadvantageous on large areas, as water does not seep away sufficiently. The processing is complex and you have to pay attention to expansion joints when laying the stones.
tips
There are special weed-inhibiting substrates. The Danish company Dansand has developed quartz sand and stone powder. These substrates have a high pH value and mimic the nature of weed-free substrates.