Sand FAQs
Millwaste/Sub-base
Sharp sand also known as washed concreting sand and coarse sand. This type of sand can be used for various applications under paving, screeding floors, for driveway under block paving.
Building Sand Can be used for bricklaying (mortar), under slabs and crazy paving joints.
20mm Ballast Can be used for foundations for garden walls, concreting in fence posts and making paths.
Millwaste/Sub-base Also known a MOT or scalpings. Millwaste is used for laying a sub-base for driveway, patios, paving and paths.
Q & A
Q. What sand should I use for under my patio?
A. Either Building Sand or Washed Concreting Sand (sharp sand).
Q. Should I use a Sub-base/ Hardcore?
A.Yes, it is important to put a sub-base down as it reduces movement. If you don’t use a sub-base it could cost a lot more in the long term due to having to re-lift the slabs and put more sand down.
Q. What ratios of sand to cement shall I use?
A. Mortar (Brick laying)- 1 cement : 5 Building sand.
Concreting - 1 cement : 2 WashedSand (Sharp Sand) : 3 20mm Aggregate.
Render - 1 cement : 5 Render/ Plastering Sand.
Screed - 1 cement : 3.5 Washed Concreting Sand (coarse sand).
These recommendations are only guidelines suggested by Castle Cement.
Q. How long will cement last?
A. Only 3 months from the date printed on the packaging, providing its not exposed to damp or wet conditions.
Q. What thickness of gravel should I use for a driveway?
A. Well we usually recommend between 1.5 – 2 inch (40-50mm) for paths and for driveways should be about 4 inch (100mm) to allow for sinking from the car driving over it.
Q. How much sub-base and sand should we use ?
A. Driveways - 4 inch (100mm) Sub-base.
(Block Paving ) - 2 inch (50mm) Sand.
Slabs - 3 inch (75mm) Sub-base
- 2inch (50mm) Sand.
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