Laying instructions

Setts

Here is our general laying advice, however, always seek local advice in case your situation is special and demands individual attention. Granite in mainland Europe is generally laid on sand, this is much cheaper than laying in cement but setts may shift over time and occasional maintenance is required. Sand laid granite is also susceptible to ruts if driven over. For further information see http://www.ihbc.org.uk/.

Laying instructions

You will need a good, strong, base to begin with – for example a well vibrated 2 – 4″ MOT 1 rubble. I highly recommend beginning with a small trial area to make sure you are happy with your base and are confident of your laying technique. Please also note the following points:

  • Any existing hard standing can be removed
  • Soft soil will require a thicker base
  • Use a membrane to prevent sand mixing with the earth
  • For large areas use an expansion joint.
  • Lay a small trial area in sand first to get the right look.

Laying in cement.

  1. Vibrate down base well with a whacker plate
  2. Lay 2 -3″ sharp sand over the base and vibrate down – this should be your basic level minus the thickness of setts and cement
  3. Along the first line lay 3″ (or 4″ if you want to drive over the pavement) of 4 : 2 : 1 dust to 8mm gravel : sharp sand : cement, then combine additives – plasticiser, and water-proofer. Be sure not to mix too dry. In mainland Europe polyester fibres are added to reduce cracking. Building or plastering sand should not be used in  a bedding cement.
  4. A primer slurry  painted on the bottom of the setts will also improve  adhesion.
  5. Make up a builders line and place stones along the first line. Knock down with rubber hammer while maintaining straightness and about a 1″ grouting depth. Keep face as clean as possible.
  6. Lay second line. When placing stones along this line be sure to align the stones along their centres rather than align each one with its side to the line as this may result in an uneven appearance.
  7. Continue with remaining lines, keeping as flat and even as possible while continuously checking lines and adjusting accordingly.
  8. Allow to harden for one week minimum, and more time if you intend to drive on it regularly. Full curing of cement to maximum strength can take up to four weeks.

Keep in mind run off, and installation of drainage pipes, as the setts will be waterproof unless you use an epoxy or lime based grout. Extra thickness cement mix is advised at the entrance to a driveway, or thicker setts (10cm) might be used.

Grouting cemented setts.

You have a number of options:

    1. The simplest method is Make up a 3 : 1 : kiln dried sand : cement (dry) mix. Mix well and brush in fully. This has to be done on a very dry day with setts completely dry. If you wish to water, use only a very fine mist.

This method is not however the strongest and may suffer frost damage in the long term. A slurry is always stronger.

  1. Use a jointing slurry from Steintec (this comes in many colours).
  2. Use an epoxy based product . This is probably the best overall solution but is the most costly. It is water permeable (puddles do not form in the joints), as well as being flexible and strong. It is also the quickest to apply, and leaves the face totally clean. If application cost it factored it may not be as expensive as it appears and certainly gives the best final effect. It offers many advantages including ease of application and working while standing being its major advantage. This product is directly from TheStoneYard.co.uk and prices are available on enquiry.
  3. An asphalt base grout from Colas also produces good results.

Laying in sand

It is preferable to have the outside rows cemented in to avoid movement; this might also be a kerbing.

  1. Lay and level 2 – 3″ of sharp sand, damp sand binds better but dry also works.
  2. Vibrate down well.
  3. Place each row along a builder’s line and firmly knock in place with a rubber hammer. This should not be deeper than about 1m or about 10 rows.
  4. Continue with remaining lines, keeping as flat and even as possible while continuously checking lines and adjusting accordingly.
  5. Lay marine ply over stone and vibrate down. This reduces stone movement.
  6. Sprinkle sand over and brush in to avoid movement.
  7. Lay next 1m keep knocked in height the same as the previous 1m row so that when it is vibrated down with the ply levels are the same. Sprinkle sand again and continue on to next 1m.
  8. When a few 1m rows are finished vibrate down again adding sand until you are happy that the stone will not move. You may consider watering in if you find there is still some movement. Finer sand can then be brushed in. This may have a few larger gradings in to help it bind. The more you vibrate the less chance of movement. A joint stabilising liquid can be used to make the joints firmer (see www.resiblock.com). You can also use granite dust/sand. This binds very well, I can supply this but it is cheaper to get it from the UK, ash is also commonly used.

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