Dry Sand Grouting
Dry sand grouting is recommended for pavers with jointing gaps smaller than 5mm in width.
Material
In South Africa, plaster sand is commonly used for sand grouting. In the rest of the world, you get proprietary packaged, paving jointing sand.
Plaster sand is not ideal to use as paving grouting, for the following reasons:
- Plaster sand contains fines, which are prone to stain concrete pavers.
- The particles of plaster sand are round and not angular. It therefore, does not create the best interlock between pavers.
- Plaster sand’s common grading analysis, does not comply with the Interlocking Concrete Pavement Institute’s (ICPI) specification.
- One struggles to source dry plaster sand.
Therefore, Cretesol now offers Specially Graded, Kiln Dried Paving Grouting/Jointing Sand, packaged in convenient 40kg bags. The particles of this jointing sand is angular, which creates superior interlock between pavers. Furthermore, the sands grading complies with the ICPI specifications for paving jointing sand.
Method
Sand is swept diagonally into the open joints, and then vibrated to ensure it is settled after which more is swept in until the gaps are filled. Using dry sand is essential as damp sand will clump and stick to pavers which will result in joins not being filled properly. Therefore, pavers also need to be completely dry before the sand can be swept in.
Grouting sand is simple to install and no rigorous cleaning is required after installation. Sand could, however, wash out of joints, and paving joints should be topped up approximately three weeks after installation and annually.
Sand grouting might wash out on steep slopes and around downpipes. Weeds are known to grow in sand joints and this generally requires regular maintenance.