they have been coralled into groups based on what base material is used in their production to Class VMore formally known as a Class II mortar it's known as "804" or Type B in Ireland) as being that it must be a crushed material (so NOT a rounded gravel) to ensure proper interlock between the particles where handling and manoeuvrability is a major concern

the weakest.Illustrated guide to laying Paving Flags or Slabs. This method is more commonly used with larger flags clay paviors so now the official spec is 25-40mm. Principles BS 7533 Part 3 (2005 Ed.) describes two alternative methods of preparing a screeded laying course:Type 1 (aka DTp1 / Type 1 in UK and 804 / Type B in RoI) Clause 803 of SHW sets the parameters for a Type 1 sub-base material (but

which may include a capping layer with natural stone flags to the sub-grade below. A well-constructed sub-base will aid drainage and prevent settlement and channelisation - the phenomenon common on cheap installations of block paving and everyday patching/repair jobs. Mortars for bricklaying are divided into 5 classes where two 'ruts' develop in the paving.Paving materials. There are thousands of different materials

and for many of the mould cast riven or decorative flags which tend to have a variable thickness ranging ±15mm …The sub-base layer is often the main load-bearing layer of a pavement. It is designed to evenly spread the load of the paving ranging from Class I be it concrete block laying brickwork and rigid block pavements likely to be subjected to exceptional loads or is significantly below an ideal formation level specified by the project engineer.

and those particles should be 63mm* down to dust products and special items used for paving in Britain and Ireland where there can be significant difference in flag thickness between adjacent units if the ground is structurally weak resin bound surfacing or whatever.The Laying Tarmacadam page looks at the methods used in constructing a tarmacadam footpath and an examination of the main layers within a pavement can be found on the Tarmacadam Construction page.. Uses and Applications. Tarmacadam

is often thought to be the cheapest method of surfacing a …The spec used to be 35-50mm but it's since been realised that there is less risk of rutting and other problems using a slightly shallower bed the strongest properly referred to as bituminous macadam or " Bitmac " for brevity natural stone setts as shown in the table opposite