Specification For Laying Of
Segmental Brick And Flagstone Pavers

Introduction:

The following specification is a guideline to assist both the contractor and client in realizing the best possible end result. It is recommended that a reputable paving contractor be used, ideally a member of the Brick Paving Institute of South Africa.
(A list of members can be found on the official web site http://www.bpisa.co.za/ )

Segmental paving is the construction of flexible paving using either paving bricks and/or paving slabs (flagstones).

The most commonly used thicknesses are 50 and 75mm.
Both are available in the Flexipave range.


Sub base

This is a fairly specialized subject and ideally should be designed by a qualified person. In the case of an industrial application, the sub base should be specified by a professional engineer. For domestic and pedestrian applications the specification can often be left up to a reputable paving contractor to do. A good sub base is essential if you want your paving to last longer than a couple of years.
The following specification is a guideline only and is not to be assumed to work for any and all applications. If in doubt please consult a qualified person.

Type A
(light, foot traffic only - paths and patios)

75mm compacted thickness of standard sub base mix available from Lafarge, compacted with a vibrating plate compactor. A compacted sub-base should not move when you walk on it.

Type B
(light foot and vehicle traffic - domestic drives, paths and patios)

75mm compacted thickness of standard sub base mix available from Lafarge, compacted with a vibrating plate compactor. As this sub-base is intended to carry the weight of a vehicle, it is essential that compaction is thorough. The finished surface of the sub-base should be dense. i.e. not open textured or with surface voids. Fill any such openness with fines or grit sand.

Type C
(foot traffic, cars, vans and small pick-up trucks not exceeding 7.5 Tons)

This is exactly the same as the Type B sub-base above, except it is 150mm thick, and this may be compacted as two 75mm layers or one 150mm layer. Compact thoroughly and make sure the final surface is 'tight' before continuing with the bedding material.

Screed

Please refer to the section on bedding sand on the web site of Brick Paving Institute of S.A. http://www.bpisa.co.za/practice.html#segmental

Laying / Grouting

Brick paving is traditionally layed butt jointed. Flag stone pavers are usually layed closely jointed with a 3 to 5mm sand joint or a 10 to 12mm mortar joint.

Under no condition should a plate compactor be used on any flag stones.

With reference to the unique textured finishes of the FlexiPave range, the 4:1 sand cement mixture is mixed dry - no water is added at all, and it is essential that the sands and cement are thoroughly mixed together in the dry state before scattering onto the dry paving surface.

The mixture then needs to be swept into the joints. Once an area has been covered, every joint should be forcibly struck with the edge of a trowel to pack down the dry mix into the joints. The process is repeated as required.

Sweeping should be at an angle of 45 to the direction of the paving joints. All surplus mix should be swept off and can be re-used to seal other areas, if required.
Alternatively, if a wet mortar mix is applied, care needs to be taken to ensure that no spillage of the mortar is left on the paving. Any spillage needs to be cleaned off immediately. The joints should be pointed allowing the level of the mortar to be slightly lower then the top surface of the pavers.

All information and specifications used on this site are intended for guidance only. You are strongly advised to seek professional advice for your project.