How to Build a Concrete Driveway

Concrete driveways are a great addition to any home and provide a permanent low maintenance solution for driving and parking your car on. Concrete driveways reduce erosion and will help keep your car cleaner and also can improve the appearance of your home.

Building a concrete driveway does require a lot or labour and can be costly. However if you are a confident DIY renovator or builder you should be able to get a great result. Below you will find step by step DIY concrete driveway instructions for building or laying your own concrete driveway.

Please remember to read the working with concrete safety information at the bottom. Remember that for such a job as a concreting a driveway you will need the help of one or more people to help you spread and finish concrete before it sets.

Concreting Tools you will need:

Timber saw, hammer and nails, concreting towels, concrete screed, and long handled concrete bull float, concrete immersion vibrator, tape measure, string line, plate compactor, shovel, metal rake, level or laser level, Mechanical towel for large areas (optional).

Step 1: Plan your Concrete Driveway

When you to start plan your concrete driveway make a plan on paper and include all your measurements. The best way is to make a scale drawing showing the exact shape and measure as this will help you with purchasing timber and pegs for the formwork, steel reinforcement mesh, and concrete volumes. Also note on your drawing if there are any pipes like sewage access pipes as the height of these may need to be changed to match the height of the concrete driveway.

Make sure your design of the concrete driveway will match your needs as it is fairly difficult to change once your new driveway is complete. You will need to pay special attention which way you need to fall the concrete driveway for storm water runoff. It is always best, if possible, to fall the driveway away from the house. However if it is not possible then you will need a drain to deal with storm water runoff. Make sure that the contour of your concrete driveway does not end up too steep so your car bottoms out or scraps while using it. For ideas to the shape and design, if possible, have a look at what other people have done in your street or area. This can give you an idea as to the shape and design and the way stormwater drains.

Step 2: Estimate the Volume of Concrete

To find out how much your concrete driveway will cost and the volume of concrete you will need, add together the measurements on your plan. For example: Look at the driveway in this photo below. It is a fairly straight double drive: 6 metres wide and 8 metres long.

• Multiply 6 metres by 8 metres = 48 square metres then
• Multiply 48 by 0.1 (for a 100mm thick slab) = 4.8 (or 48 x 0.15 for a 150mm thick concrete slab= 7.2)
• 4.8 Plus 10% = 5.28 = 5.3 to order or 7.2 plus 10% = 7.92 = 8 to order.
• Concrete order = 5.3 cubic metres or 8 cubic metres for 150mm thick.

Remember to order 10% more concrete then you need to cover imperfections in the formwork and ground levels. Concrete is delivered in set increments, for example you cannot order 7.92 cubic metres of concrete you must order 8 cubic metres.

Remember to add the cost of the timber formwork, pegs, reinforcing mesh and any hire tools. Now you should be able to add all your costs together to get a true estimate of your concrete driveway.

Step 3: Check with your local council or building authority

Before you begin check with your local council regarding any fees, storm water plans, or regulations.

Step4: Ground Work for your Concrete driveway

You must pay attention to the type of ground you wish to build the concrete driveway onto. If your ground is very sand or wet you will need to dig out and add road base and mechanically compact the area. This will provide a solid stable base on which to lay your concrete. Walk behind plate compactors are easy to use and can be hired to compact the base on which you wish to build your concrete driveway. If you are in any doubt consult a builder or a civil engineer for advice before you start so your investment of time and money are not wasted. Remove the top layer soil or any soil with grass in it and pour in builders sand and level out ready to start your formwork.

Step 5: Lay in your formwork

Start by loosely laying the timber in place without nailing or screwing together. Then double check that your work in square to your house or the street or exactly in the place where you want it. It is important to get this right as the concrete will mould and set exactly to the formwork. Start hammering in your timber pegs at the corners first checking for square as you go. It is possible to create rounded areas and circles, if desired, by using a thinner flexible piece of timber. Your pegs should be about a metre or 3 feet apart and half that for supporting circular areas with thin formwork boards.

If your concrete driveway is 100mm thick use 100 x 50mm timber (2 x 4). Cut your pegs off level with the top of the slab or hammer them until they are level. This way you will be able to screed off the top of the concrete driveway properly.

Step 6: Install in Reinforcing Mesh and prepare any Pipes

Cut your reinforcing mesh to fit inside your formwork to be covered by a minimum of 40mm of concrete. The mesh should be a minimum of 40mm in from the sides of the formwork. As you lay in your reinforcing mesh you may need more than one piece in which case you will need to overlap and wire together. You must overlap your reinforcing mesh a minimum of 225mm. Make sure you use bar chairs to lift your mesh to the correct height in the concrete. Your mesh should be about the middle of the slab and no closer to the top of the slab than 40mm minimum.

For example: If your concrete driveway is 100mm or 4 inches thick you will need 50mm or 2 inch bar chairs so your reinforcing mesh is in the middle of the slab. Also make sure it is 40 to 50mm away from the side of the slab. If you do not do this the reinforcing mesh can rust and break the concrete and ruin the whole concrete driveway. Note: For a 150mm thick concrete driveway you can use 75mm or 100mm bar chairs.

You can also use fibre reinforced concrete in which you will not need to use any reinforcing mesh into your slab.

Step 7: Pouring the concrete

Plan the concrete pour carefully taking into consideration whether the concrete truck can pour directly into the form work or whether you will need a concrete pump as well. If a concrete pumping truck is needed you will need to book them in advance and have them come and set up half an hour to an hour before the concrete truck arrives. Then the concrete truck can pour directly into the concrete pumping truck. Concrete pumping trucks are paid for by the hour so it is important to have everything ready and the concrete truck booked for a correct time. Your concrete pump operator will be able to advise you on the timing needed and when to book the concrete to be delivered.

Step 8: Spread the Concrete evenly and remove air bubbles

Spread the concrete evenly but roughly with a shovel or straight piece of timber or straight edge. Using an immersion vibrating pole (available from hire shops) vibrate the concrete to remove the air trapped in it. This will make it stronger and denser. Spread roughly and screed the top of the concrete so that it is fairly good but be careful not to over work the concrete at this stage as you will just work the water up and out of the concrete. Your concrete driveway should be fairly smooth with some surface water on it. It is important to wait until the concrete starts to set so you can just stand on it without too much damage before moving on to the next step.

Step 9: Finishing the Concrete Driveway

It is at this step that you colour your concrete or use a stencil to create a pattern or a concrete stamp for a pattern and a texture. You can also just towel your drive smooth and run a yard broom across it for a non slip surface. There are many different and beautiful ways to finish concrete so look around your area at what other people have done and take note of what you like.

The basic way to finish your concrete is to pour coloured concrete in and just towel it to an even surface with a timber float. This will give you a non slip surface without being to aggressive. The most common way is to pour in normal grey concrete and throw powdered colour across the wet concrete and towel in. This way you work the colour into the top part of the concrete and finish with a towelled finish.

To stencil a pattern across the top visit your stencil supplier with your exact measurements of the concrete driveway. Your stencil supplier will cut you a stencil to fit your driveway. When the slab is starting to set roll out the stencil and press towel in then throw across the colour and towel in and finish. Then allow the slab to set and the next day carefully pull the stencil up and allow the concrete driveway to cure.

Step 10: Cure and Seal

To cure your concrete driveway it is important that the concrete does not dry out to quickly. In hot weather, lightly spray with water, and cover with plastic sheets for 3 to 7 days. It is best not drive on the concrete driveway for at least seven days. If possible, allow to cure for 14 days before driving on it and then after 4 weeks seal with a quality clear concrete sealer.

Working with Concrete Safety Warning

• Avoid contact with your eyes or skin by wearing proper personal protective equipment like chemical resistant gloves and safety glasses.
• Concrete can cause severe burns and or dermatitis because of its high alkaline chemical structure.
• If you get concrete on your skin or in your eyes wash off immediately with clean water.
• Concrete skin burns can show up many hours after contact.

Concrete is heavy to work with and if you do not finish your work in time the concrete will set as you leave it. So be prepared with tools and people to help you or your result will be less than desirable.

Concreting your own driveway can be rewarding and can save you a heap of money if done correctly. The best way is to follow the steps and consult experienced people in your area on any part that you are not confident about. Happy concreting!