Preparing for a concrete floor is the best way to ensure a smooth, hassle-free experience and a concrete flooring installation you can be proud of.
Before you receive your concrete delivery from Flowmix, here are four simple steps to prepare the site for your concrete pour.
1: Prepare The Foundation
Before you even think about pouring concrete, take a moment to focus on the foundation. A weak or uneven base will leave your concrete prone to cracking and crumbling, no matter how small or large the project is. The first step is preparing for a concrete floor to create a strong, level surface.
Start by digging down to the necessary depth. If you’re working on foundations or floor slabs, don’t forget to factor in space for the subbase, a damp-proof membrane, and the concrete itself. Remember to clear the area of stones, plants, and any debris that could interfere with your work.
Pro Tip: When preparing for a concrete floor, consider how water will flow around your concrete, especially if it’s outdoors or in a spot prone to moisture. Adding drainage solutions—like channels or weep holes—can prevent water from pooling under the slab and gradually weakening it.
Taking the time now to handle these details will help prevent problems down the road!
2: Lay The Subbase And Damp-Proof Membrane
After excavating the area to the correct depth, it’s time to prepare for the concrete pour by laying the subbase.
Note: If unsure of the depth required, contact the Flowmix team for advice.
A subbase is a layer of aggregate material that sits snugly between the subgrade (the compacted soil beneath) and the base course. Its primary job is to create a solid, load-bearing foundation that can handle the weight and wear of outdoor spaces like driveways, gardens, and pathways.
Without a properly laid subbase, your paving risks shifting, cracking, or sinking over time. The foundation ensures everything above it stays level and durable, regardless of traffic or weather conditions.
The key when preparing for a concrete floor, is to consider what job the concrete will do. The subbase thickness is an essential element of preparing for a concrete floor as it directly affects how much weight the concrete can handle.
- Lighter Applications: Gravel or crushed stone works well.
- Heavy-Duty Use: For high-traffic areas, you’ll want to go the extra mile with a reinforced subbase—compacted stone or even a concrete foundation beneath the slab might be your best bet.
Don’t forget about the damp-proof membrane (DPM). This thin layer prevents moisture from creeping up into your slab, which can lead to problems like efflorescence or damage to flooring materials. Moreover, it ensures the fresh concrete doesn’t dry out too quickly, giving you a stronger, more durable finish.
Taking these steps might feel like extra work, but they’re the secret to a concrete slab that stands the test of time.
3: Build A Frame To Hold it All Together
Before the concrete pouring, building a sturdy frame to shape and support the concrete as it sets is essential. Typically, this frame is made from 25mm-thick timber planks, carefully positioned and secured to stay in place throughout the pour. The thickness of the frame should match the desired thickness of your concrete slab, so precise measurements are key.
Getting the frame level and square is critical. Grab a spirit level and tape measure to double-check everything is aligned. A crooked or uneven frame can leave you with a misaligned slab, so don’t skip this step!
For larger projects, consider adding extra bracing to keep the frame steady and prevent any shifting under the weight of the wet concrete.
Building a solid, well-measured frame will ensure your slab turns out smooth, even, and ready to handle whatever comes its way.
Read: Concrete Slump Test: What is it & Why Does It Matter?
4: Get Ready For The Concrete Delivery
The final step before the concrete arrives is to prepare your site for a smooth and efficient pour. A little planning at this stage goes a long way in preventing delays and ensuring the concrete doesn’t start curing prematurely.
- Start by clearing paths for easy access, especially if the terrain is uneven or sloped.
- Lay down planks or supports where needed.
- Double-check you have all the tools and labour required for the job.
Ensure your equipment is ready to go—wheelbarrows, shovels, and trowels are must-haves for evenly distributing the concrete. If it’s a larger pour, you’ll likely need extra hands to help with levelling, smoothing, and finishing the surface as quickly as possible. Timing is everything, and being well-prepared ensures you maintain the quality of the finish.
Note: Hiring a concrete line pump can significantly speed up the concrete pour, minimise mess and wastage and reduce the need for intensive manual labour. Flowmix can supply a 200’ concrete line pump. Contact the Flowmix team for details.
When preparing for a concrete floor, don’t forget to check the weather forecast! Extreme heat is a contractor’s nightmare, as it can cause the concrete to cure too quickly. So, on hot days, wetting the subbase or using retarders can help.
Conversely, cold temperatures can slow curing or even cause freezing. In that case, consider using heaters or thermal blankets to keep the concrete at an optimal temperature.
A little foresight at this final stage can help ensure your project has a flawless pour and excellent, long-lasting results.
How Flowmix Can Help With Your Project
Flowmix has two plants, Gloucester and Walsall. We provide ready-mix concrete, mix on-site and liquid screed.
In addition, you can hire a 200′ concrete line pump to reduce manual labour and associated costs, increase efficiency, reduce wastage and clean up. Moreover, we also provide interlocking concrete blocks for temporary or permanent barriers.
Flowmix has the BSA-approved Ready Mix Concrete Kitemark KM683844, a certification that “confirms a product or service’s claim has been independently and repeatedly tested by experts” (source BSI).
Flowmix Tewkesbury: 01684 217888 Flowmix Walsall: Tel: 01922 741731
FAQs
How Do I Ensure My Subfloor Is Ready For Concrete?
Before pouring concrete, ensure the subfloor is level, compacted, and debris-free. A proper base, such as gravel or sand, helps prevent cracking and ensures durability.
Do I Need To Use A Moisture Barrier Before Laying Concrete?
A moisture barrier is essential, especially for indoor spaces or areas prone to dampness. It prevents water from seeping through and reduces the risk of cracks and mould growth.
How Long Should I Wait Before Using My New Concrete Floor?
Concrete typically takes 24-48 hours to dry for light foot traffic, but complete curing can take up to 28 days. Avoid placing heavy loads or installing flooring until the concrete has fully cured.
What Tools Do I Need To Prepare For A Concrete Floor?
You’ll need tools like a level, tamper, rake, measuring tape, moisture barrier, and rebar or wire mesh (for reinforcement). When preparing for a concrete floor ensures a smooth and durable finish.
Can I Pour Concrete Over An Existing Floor?
The existing floor must be clean, level, and structurally sound. Applying a bonding agent and roughening the surface will help the new concrete adhere properly.