How to Lay Block Paving

Laying block paving driveways and patios. Advice for the professional and D.I.Y. enthusiast. Here are some helpful resources to help with the laying of block paving, Groundwork's that are needed to lay paving, choice of materials when learning to lay block paving. Learn tips on installing block paving, paving designs and patterns, and the difference between clay and concrete block paving, and many other useful information tips and advice to do with the aspects of the installation of block paving for driveways,paths and patios..

Preparation of the area to be block paved

The old driveway,old tarmac,old concrete,vegetation and the soil sub-base that is to form the new driveway, path or patio should be removed to a depth of around 200 mm (8inch.) depending on the driveway ground that you are excavating. *If the ground is soft then you may have to dig deeper, *if the ground is very hard then maybe not as much. The finished new driveway,path or patio needs to be 150 mm (6 inch) below any damp proof course that you may have o your house or garage. Dig out the driveway to a depth of 200mm (8 inch) below the finished height of the paving. A fall of at least 1:60 needs to be established to allow water to run away to a drainage point.

* Before digging out the area to be paved it helps if you know the size of the block paving you are going to be laying. These measurements are based on using a block paver that has a depth of 50mm. There are though, 60 and 80 mm pavers available for areas that will recieve heavier vehicles. 80 mm sized bricks are normally used for commercial paving projects.

A good quality weed control fabric should then be used to cover the whole area that is to be paved. (other names .. geotextiles,ground stabilization sheet.)Weed control Fabric comes in different sizes and gauges so its worth checking with the supplier that you get the correct size and strength for its use on your paving project. Weed control fabric is also necessary for ground stabilization. It acts like a kind of bridge, if any soil should later settle, then its supported all around by the sheet carrying its weight. It also stops the spread of the aggregates into the sub-base.

Edge restraints to the whole perimeter need to be considered when doing the groundwork's. The edge restraint could be the side of a house or an external pavement, but where there is no solid edge to work to, a kerb restraint needs to laid. Any edging kerbs need to be bedded on a concrete bed to a depth of approximate 100 mm(4 inch ), they usually need to hunched up behind with concrete at an angel of 45 degrees , this stops the kerbs from moving.

Any inspection chambers (manhole covers) also need to be set in place. Advise should always be sought especially if the cover is to take the weight of a vehicle. Always set the cover to the correct height and set in place with cement or concrete. A string line between 2 finished levels should help with this.

Apply the stone (hardcore stone) to the whole area. When ordering your stone it is important that you get the correct stone for the job, always quote the purpose of the stone to your supplier so they can ensure that you get the correct type of stone. (most cases use Mot type 1 stone)

The stone needs to be at a sufficient depth that when compacted there is still enough height left for the block paving and the screed sand.
Example. If you are using 50mm block pavers and 50 mm of sand the finished height of the stone needs to be 100mm below the finished level.

Compact the whole area with a heavy plate compactor or whacker plate at least 10 or 11 times or until you feel the area is solid.

Grit sand

Always try to use grit sand and not building sand when laying block paving on sand. The grit sand supports your paving better than normal building sand.
and allows for a better drainage should you get a penetration of water into your paving. Grit sand usually arrives in bulk bags. keeping it neat and tidy alongside your home. Grit sand wherever possible should be kept out of heavy rain. This stops one area of sand being water saturated and makes laying the sand easier and lighter.

Choice of paving.

You have to consider when choosing block paving that it usually takes a day or two to arrive from the point of ordering your block paving to having your block paving delivered.
You will need a safe place to keep your paving and aggregates (Sand,cement,stone) safe from the highway pavement, road and pedestrians.
Remember "where there's blame there's a claim".

Sand screed

Sand screeds can be done with a number of different methods from the easiest method of a few old timber latts,to the more sophisticated method of using a purpose built sand screed.

The runners or timber latts that act as rails for the sand screed to run on (bit like a railway track) They need to be firmly set in place so not to move when running the screening timber of rake over the rails.This can be done with compacted sand underneath the rails.
Always check to see that the rails don't dip in any areas because if the do, when you lay your paving you will have hollows and puddles where your sand was uneven.

Take the depth of the paving (example 50mm ,most common block paving type) + 5mm (1/4 inch) for compacting down of the paving and set the latt or rail to that depth below the finished height required for the completed paving. Then when blocks have been laid and compacted the paving should be at the finished level needed to allow the drainage of water to drains or run off points.
A string line pulled tight and a good spirit level between two points of the finished height will help you achieve this.You then need to level the sand with a good straight edged timber (usually a depth of 100mm and a few centimeters short of the width of the driveway or patio) drawn along the screed rails. This is normally a 2 person operation if the width of the drive or patio is bigger than two meters wide. We always recommend that once the first screed of sand has taken place, that you compact the sand using a plate vibrator making sure you don't touch the screed rails.
This allows any small divits or uneven areas of sand to be compacted and strengthened.

Then you need to do a second sand screed to the whole area.
You are now ready to lay your paving.

Laying the block paving

Try to choose a dry day to lay your paving. (very hard, i know. )Block paving carts for the carrying of block paving can be purchased or hired from any good hire shop. Or buy online here

Always try to work from several Packs of paving at a time to ensure an even distribution of colours and shades is achieved. Always try to work uphill when laying the paving as each block pavior then rests on the other and stops the blocks from spreading.

Start from the longest straight run that you have to help with keeping the blocks uniformal. Again a string line can be used to make sure your paving is running straight.
Lay the blocks hand tight in the pattern that you have chosen.

Cutting the paving

After all the block pavers have been laid , you need to cut paving blocks for the infill areas so that the paving is up tight to the finished edge all around the perimeter of the paving. Pieces of block paving that are less than a quarter of the size of the paver are best avoided.

There are several ways to cut the paving. For a diy block paving project we would recommend a block splitter.
These are quite cheap to hire and need no electricity or petrol to use .The other option is for a paving saw that uses petrol or electricity.
Usually a 9 inch grinder or a petrol saw. A certain degree of confidence and knowledge is needed when using these to cut concrete or clay pavers.
Advise should always be sought when contemplating using a high powered cutter.
A good quality diamond blade is always helpful to rather than the normal carbon blades.

Compacting the block paving

Before any compaction of the paving takes place you first need to sweep clean the paved area. This stops any debris being vibrated down between the joints, thus distorting the laying pattern.

Compaction should again be done with a whacker plate. This should be done to the whole paving area 2 or 3 times. Particular attention should be made when compacting the edges. The paving edges need to be level to stop any trip points. Care should also be taken around sensitive areas such as walls , drains or inspection covers. If unsure try using a rubber mallet or the wooden end of a lump hammer, to any difficult areas.

Kiln dried sanding of the block paving

Always allow the paving to be completely dry before you apply the finishing sand. Dry sand needs to be used for the sanding as it then runs freely into the joints without clogging up. Kiln dried sand is always best as it is of a fine grade and dried in a kiln before being bagged so should be dry.

Usually 1 bag of kiln dried sand is sufficient for about 10-15 square meters of paving.

Once the whole area has been sanded, sweep off any excess sand and save. Apply the plate compactor again over the pavement for a couple of times . Again use a mallet for sensitive areas. The dry sand will seem to disappear down the joints of the paving.

* The compacting of the sand into the joints causes friction between the paviors thus strengthening the paving by forcing the blocks against one another. This is rather like placing your arms against the inside of a door casing and lifting your feet of the ground. (if you think of this as how the block pavers work against one another)
I once heard that if done correctly and in a slight arc , that you should be abe to dig out a few square meters of sand and stone from under your paving and then still be able to use .
I wouldn't recommend trying though.Once the compaction of the blocks and sand has taken place the whole area then needs to be re-sanded again.

Ensure the sand is filled to the top of the joints of the paving and sweep off any excess. Always keep a small amount of kiln dried sand for any later infill's of sand that get lost due to wind and rain.

Well done you've finished ...

All that's left to do is clean the area and enjoy you new block paving driveway or patio