"All in Ballast" refers to a mixture of sand and gravel that is used to make concrete. In general the sizing of the grains/stones varies from 0.1mm to 20mm and is produced using a mixture of sharp sand and 4-20mm pea shingle.
Concrete is a mixture of sand, gravel (Ballast) and cement that sets hard within a few hours of being mixed with water. The proportions of ballast, cement and and water are varied to give concretes of different strengths and workability. In general the less water that is used in the initial mix, the stronger the resulting concrete will be when set.
For general building purposes our 20mm Ballast is suitable for many purposes. These include, mixing concrete for foundations and footings and making a concrete slab for your conservatory, shed, garden or extension. Uses in the garden further extend to making foundations for garden walls, concreting in fence posts and making paths. For a general purpose concrete mix use 1 part cement to 6 parts ballast. Where everything is dry, a water to cement ratio of 0.55 should be used. As a guide, when your concrete is mixed and ready to use it should be able to support itself, almost fully, in a heap on a shovel.