What is the best sub-base for a patio?

What is the best sub-base for a patio?

‘ The most common granular aggregate sub-base is DoT (Department of Transport) Type 1 and Type 3 Limestone. They are both crushed stone: Type 1 has a maximum permitted top size of 63mm, graded down to dust; and Type 3 is an open-graded 40mm unbound mixture with a reduced amount of fines.

Do you need sub-base for patio?

Do I really need a Sub-base? The short answer is: if the pavement will be trafficked by vehicles, then yes, but if it will be foot-traffic only, then not necessarily. The type of paving or surfacing that will be used is one of the key factors in determining whether a sub-base will be required.

How deep should a patio sub-base be?

Dig a depth of around 150mm across the whole area, making sure the soil is evenly compacted. Then tip in the sub-base, raking it into a consistent depth of 100mm. Make sure it’s smooth, flat and firm.

Can you use gravel as a sub-base for patio?

Gravel patio benefits Easy to lay – gravel is an easy material to lay due to its size compared with alternative patio surfaces such as decking or concrete paving. Economical – gravel patios are more affordable than other patio surfacing solutions and do not require the help of a landscaping professional to create.

Can I use old slabs as sub-base?

It will be fine.

Can I use old bricks as sub-base?

Recycled crushed brick and crushed concrete are viable substitute materials for natural construction materials in engineering applications such as pavement sub-base and other road construction applications.

Can I use 20mm gravel as a sub-base?

0-20mm ballast is perfect for sub-base and concrete foundations. 20mm screened ballast is versatile and can be used on driveways, footpaths, oversite fill as well as sub-bases.

What can I use for sub base?

You can compact this using a wacker plate. Once you have laid your sub base you can either lay a 25mm depth of sharp sand. However we recommend using a mortar mix as this will provide a longer lasting base which will prevent weed growth and the gradual movement of slabs.

Can broken slabs be used as hardcore?

They’ll be absolutely fine as long as you break them up well – hard work though!! Put dolomite hardcore on top as this compacts better with the wacker.

What can I use as a sub base for a patio?


  • Paving slabs.
  • MOT type 1 hardcore or sub-base material.
  • Sharp sand or All in ballast.
  • Cement.
  • Fine, kiln-dried block paving sand – for jointing 10mm or smaller joints.
  • Building sand – for jointing larger joints.
  • Long timber straight edge – for ensuring your sub-base is level.

What can I use instead of sub base?

Crushed concrete is a mostly recycled material making it great for builds with an emphasis on their environmental impact. Gathered from old sites and construction projects, crushed concrete can be used to fill cavities, paths and sub-bases.

Can I use old slabs as sub base?

What’s the purpose of a sub base in paving?

The sub-base is the main load-bearing layer of paving construction. A well-designed sub-base should evenly spread the load of traffic, whether pedestrian or vehicular, down to the sub-grade, also known as the formation level.

How much sub base do I need for patio?

Always a minimum of 100mm sub-base of crushed concrete/type 1 over a weed suppressant membrane.make sure to hire a whacker plate to compact this,readily available at all hire stores for approx £35 for weekend.

What should be the thickness of a sub base?

A finished sub-base should not deviate from the correct level by more than 10mm, and should reflect the final profile of the paving. The bedding layer above the sub-base ought to be a constant thickness to avoid differential settlement. There are a number of separate pages which consider various sub-base FAQs including…

What do you need to know about sub-base design?

A well-designed sub-base should evenly spread the load of traffic, whether pedestrian or vehicular, down to the sub-grade, also known as the formation level. Best practice usually stipulates a geotextile non-woven membrane (e.g. Terram 1000), which acts as a filtration/ separation layer between the subgrade and sub-base.