I intend to lay carpet stones in an area of the garden which gets very light foot traffic. The Bradstones brochure says for a "rustic effect" I can use sharp sand without cement as a base and to fill.
Am I likely to have any problems without cement? Also, how much sand will I need per square metre of stones?
Sand for carpet stones
Carpet Stones for patio areas are sometimes laid in much the same way as standard block paving, but the jointing is a problem, in that you can't (or shouldn't) use a rigid jointing material (such as mortar), and the wide joints make a flexible jointing medium (such as kiln-dried sand) open to abuse by weeds and the weather. The best solution for this is to use a limestone dust as a topping for the joints, as this almost 'sets' and gives a bit more protection from scour.
However, I'm not convinced that this is always a good methodology to use, even on a light-use pavement such as a patio. If the joints were closer, something less than 7mm, then I'd be more comfortable with it, but because they are 12-15mm in width, I prefer a rigid joint, so I'd opt for a rigid bed, and lay the mats on my usual patio flags bedding mix, which is 10 parts grit sand to 1 part cement, and then use a good mortar (a Class II) to point the joints.
Assuming you use a typical 40-50mm deep bed, then you should get around 10 square metres from each tonne of grit sand.
However, I'm not convinced that this is always a good methodology to use, even on a light-use pavement such as a patio. If the joints were closer, something less than 7mm, then I'd be more comfortable with it, but because they are 12-15mm in width, I prefer a rigid joint, so I'd opt for a rigid bed, and lay the mats on my usual patio flags bedding mix, which is 10 parts grit sand to 1 part cement, and then use a good mortar (a Class II) to point the joints.
Assuming you use a typical 40-50mm deep bed, then you should get around 10 square metres from each tonne of grit sand.