The correct preparation of the area to be paved, is vital to ensure the paving remains level over time and the ponding of water, in the paved area, due to subsidence, is prevented.
A joint size of 8-10mm is recommended. Joints to coincide or can be stag- gered like a brick wall.
GENERAL PREPARATION PROCEDURE
In preparation of the area to be paved, excavate the ground to a fall, with a minimum 1-50mm fall, so that any water will flow to the lowest point. It must be planned that the top of the paving is a minimum of 50mm below the damp proof course, adjacent to any building. Any exposed foundation works must be protected with an appropriate plastic membrane.
Sub-grade – The area known as the sub-grade, is the lower area of the earth, which bears the pedestrian or vehicular load. All vegetation and top soil must be removed and the ground shaped to a fall and compacted in prepara- tion of the sub-grade. (See diagram)
Base-course – the base-course is placed on top of the sub-grade and consists of a course gravel or G5 crusher run mix (i.e. +/- 38mm stone to dust) available from most local stone quarries and can be further stabilized by adding cement. The base-course varies in thickness between 50mm -120mm, depending on the quality of the sub-grade and whether the paved area is for a footpath or driveway. Footpaths can be laid without a base- course, however it is essential for driveways. The sub-grade must however be compact and uniform, for either application.
The base-course gravel layer of the + 38mm stone to dust, should be tightly compacted by using a mechanized vibrating roller.
Bedding course - This is the final upper layer, that the pavers are laid into and consists of graded, washed river sand 20-30mm thick and is to be screeded level with a builders straight edge, however still ensuring the falls established in the sub grade are maintained. Moisten the river sand prior to placing of the pavers.
Cement may be added to the base-course and bedding course at a dosage of 10-20% depending on the strength required, to further stabilize these layers. Use a builders line to set at 90° angles to one another out and main- tain your levels while paving.
TRANSPORTATION AND ON SITE HANDLING OF PRODUCTS
Pavers are best transported in an upright position on pallets and once of- floaded, they should be carried back to back to avoid surface damage.
LAYING PROCEDURE OF PAVERS AND COBBLES
Our pavers and cobbles do have variances in dimensions and colours. Use a white non marking rubber mallet to bed the pavers, to ensure that the pavers and cobbles are laid to a level top surface.
Any uneven pavers should be rotated to match adjoining pavers, or replaced and used for cutting. Allow 10% extra for wastage due to cutting when ordering. Chipped products should be used for cutting where pos- sible. Pavers and Cobbles can be cut using an angle grinder with a diamond tipped segmented blade.
COMPACTION PROCESS OF PAVING AFTER PLACEMENT
It is recommended that newly laid pavers be compacted by:
A light roller compactor with the vibrator switch off!
This is the method to be used for cobbles and pavers.
Before running the mechanical roller over the paved area, a +/- 10-20mm thick non-marking rubber matt or thick carpet must be placed over the pavers to provide protection and avoid damage from the steel roller drums.
STRUCTURAL FIXING OF THE OUTER EDGE PAVER
It is important to bed the outer most edge pavers in a concrete 4:1 river sand cement screed, with a pure cement slurry beneath to bond it to the screed.
(a.) Grouting of the joints of simulated stone and semi polished and polished pavers and cobbles (not for exposed aggregate)
A joint size of 8-10mm is recommended!
Thoroughly wet the pavers prior to grouting to prevent grout staining!
A matching factory blended grout is recommended for the best finish. When applying the grout, mix the grout to a wet creamy consistency in a bucket and then pour the grout over the newly paved area and brush it with a soft bristled broom or squeegee into the joints. Ensure that any excess grout is washed off the textured surface with a fine hose spray, or wiped away with a sponge immediately! (The sponge must be rinsed frequently throughout this process, to avoid grout smeared stains)
Do not walk or drive over the newly laid pavers, until grouting and screeded edge pavers have cured i.e. 7-10 days later.
Cordon off the area to enforce this. Always ensure the pavers are left clean after grouting or paving each day.
(b.) Grouting of “exposed aggregate paving”
It is recommended to use a factory blended matching grout for the exposed aggregate paving with a joint size of 8-10mm!
The surface of the pavers should be dry, prior to grouting the exposed aggregate pavers.
The grout is mixed into a semi dry mixture, such that it is slightly crumbly, but can be compressed into a ball when clenched in one’s fist.
This mixture is to be carefully worked into the joints, with a hand trowel and then pointed using a rounded 10mm jointing tool.
Any excess grout is to be brushed off +/- 40 minutes to an hour later, ensuring the pavers are left free of any grout on the surface of the pavers before the days work is completed.
Cure the grouting the following day by watering the paving and joints the day after grouting.
+/- 115kg/m2 (Pavers and Cobbles)
Pavers - 300x300x50mm Cobbles - 95x95x50mm
(+/- 3mm in thickness)
(+/- 1mm in outer dimentions)
Sealants prevent staining and enhance the colour of the pavers and cob- bles, however it is optional.
Ensure sufficient drying time to allow the pavers to dry thoroughly, before applying the sealant.
SQT Union Terrazzo sealer is recommended for more colour enhance- ment and our acrylic Fast Sealer for a more matt appearance.
Copings and pavers around salt chlorinated swimming pools should be sealed but pavers must be totally dry and free from efflorescence prior to sealing.
Test a small area, prior to the use of a sealer, to ensure one (the client) is satisfied with the end result.
Once a sealant is applied additional coats may be required in time, de- pending on exposure to the sun and the amount of foot traffic.