How To Lay Paving Slabs On Concrete?

So, you’ve chosen the ideal paving slabs for your new patio and opted to save some money by installing them yourself. Now, the challenge is determining the most suitable way to lay the paving flags that will work well for both you and your garden. Although laying paving slabs on concrete may appear challenging, following these steps carefully should enable you to complete this project efficiently. Don’t be intimidated by this do-it-yourself task; instead, think about the positive impact of paving on your garden. It has the potential to enhance the aesthetics and functionality of your outdoor space, with paving serving as just the initial step in this transformation!

Read More: How To Lay Floor Tiles On Concrete?

Laying Paving Slabs On Concrete

Option 1: Installing Paving Slabs on a New Concrete Bed

Preparing the New Concrete Bed

While laying paving slabs on a new concrete bed requires more time, it provides greater flexibility in patio placement. Opt for this method if existing foundations are irreparably damaged, ensuring a solid base for a durable patio.

Here are the 11 tools and equipment you’ll need to prepare a new concrete bed:

•     Measuring tape
•     Wooden pegs
•     String
•     Shovel
•     Spirit level
•     Rake
•     Garden roller/tamper
•     MOT Type 1 sub-base
•     Cement
•     Sharp sand
•     Wheelbarrow

To prepare the new concrete bed, follow these six straightforward steps:

1. Measure the intended paving area, marking it with wooden pegs connected by string.
2. Dig out the marked area to a depth of 105mm, removing any vegetation, roots, or topsoil. Set the gradient at a 1 in 80 fall for proper water runoff.
3. Level the surface using a rake and spirit level, or a garden roller/tamper for added convenience.
4. Fill the area with 70mm of MOT Type 1 sub-base, compacting it down to 50mm for a level surface.
5. Mix the concrete by hand in a wheelbarrow. Refer to our guide on how to mix mortar for paving for more details.
6. Add 30mm of the concrete mix on top of the sub-base, compacting it down again for a level surface. Your preparation is now complete!

Read More: How Many Concrete Blocks On A Pallet?

Starting with Installing Paving Slabs on New Concrete

With the new domestic concrete bed ready, it’s time to start laying pavers to form your patio. Keep in mind that this process needs to be completed fairly quickly before the concrete base dries and hardens.

Here are the eight tools and equipment you’ll need:

•     Knee pads
•     Thick gloves
•     Your chosen pavers
•     Rubber mallet
•     Spirit level
•     Tarpaulin
•     Jointing compound
•     Hard-bristled brush

Follow these seven simple steps to lay slabs on concrete without any hassle:

1. For safety, always wear knee pads and thick gloves when placing slabs into wet concrete.
2. Lay the first paving slab in place, gently securing it to the concrete bed with a rubber mallet. Check the surface with a spirit level before moving on to the next paver.
3. Lower the next paver into place, leaving an 8-10mm gap next to the first slab. Again, gently tap down with a rubber mallet and ensure the surface is even.
4. Repeat this process until you’ve paved over the entire concrete bed, maintaining 8-10mm gaps between each slab.
5. Wait 24-48 hours for the concrete bed to dry and secure your pavers in place. If rain is forecasted during this time, cover the area with tarpaulin.
6. Once the concrete bed is dry, fill the 8-10mm gaps with jointing compound, binding your pavers together.
7. Remove any excess jointing compound with a hard-bristled brush, and there you have it—a brand-new patio!

Read More: How To Get Paint Off Concrete?

Option 2: How To Lay Slabs Over Old Concrete

Preparing the New Concrete Bed

Start by gathering all the necessary tools and materials for the project to maintain organization during the work.

Wear protective gloves to minimize messiness during the project, as it can get a bit dirty.

Repair any cracks or damage in the concrete before beginning. If the damage is extensive, it’s advisable to refrain from paving, as it may harm the slabs over time.

Prepare the concrete surface by thoroughly cleaning it. Utilize a brush with solid bristles and clean the concrete using water, such as with a garden hose. A cleaner surface facilitates better adhesion of the slabs. Allow any wet areas to dry before proceeding to the next step.

Prepare Paving Slabs

Now, it’s time to prepare the paving slabs. Apply primer to the back of the slabs for secure adhesion.

Mix Mortar

Gather sand, cement, water, and a wheelbarrow to create the mortar mix. Achieve the right consistency—usually, a mixture of four parts sand, one part cement, and one part water. Safety is crucial during this step, so consider wearing PPE (mask, goggles, and gloves) to protect yourself from inhaling excess powder.

Lay Mortar

After mixing the mortar, apply a 30mm layer evenly and smoothly. Excessive mortar can lead to cracking over time and prolonged setting. Mortar acts as the glue in construction projects.

Laying Paving Slabs on Concrete

Once the mortar is applied, lay the paving slabs, leaving a 10mm gap between them. The spirit level can help you with even placement. Once satisfied with the position, use a mallet to secure the slabs in place.

Fill Gaps

Once all slabs are in place, fill the gaps with mortar, smoothing the mixture between each slab. Avoid getting the mixture on the slab surface, as it can be challenging to remove and may cause staining.

Allow 24 hours for the paving to dry. During this period, avoid placing heavy objects or walking on the surface. In adverse weather conditions, drying may take up to 72 hours.

Read More: How To Make A Concrete Base For Your Shed?

Ending Notes

To make sure you get the best quality domestic concrete for your project, contact Ready Mix Concrete London. We’ll be happy to get this task, of supplying the best possible concrete, off your hands so you can only focus on laying paving slabs on concrete.