How to Get Your Outdoor Space Ready for Porcelain Paving Installation

At Caledonian Stone, we believe that a beautiful, long-lasting patio starts well before the first porcelain slab is laid. Proper site preparation is the foundation — literally — for a flawless, professional finish. 

Whether you’re creating a sleek entertaining terrace, a peaceful garden pathway, or a full landscape transformation, investing time in ground preparation, drainage planning, levelling, and clearing ensures your porcelain paving will not only look incredible but perform perfectly for years to come. 

Here’s everything you need to know before installation begins.

1. Clear the Site Thoroughly

Why it matters:
Vegetation, old turf, debris, and even existing worn-out patios must all be removed to create a clean, stable starting point. 

How to do it: 

• Mark Out the Area: Use string lines, spray paint, or pegs to define the paving space clearly. 

• Remove Surface Layers: Strip away grass, plants, weeds, and any loose topsoil to a depth of at least 150–200mm (deeper if the ground is soft). 

• Dig Out Old Surfaces: If you’re replacing an existing patio, lift old slabs fully and remove any broken mortar or base material that could compromise stability. 

Caledonian Stone Tip:
Don’t leave any roots or organic matter behind — these decompose over time and can cause settlement or instability under your porcelain paving. 

2. Assess and Prepare the Ground

Why it matters:
The ground needs to be firm and uniform to support the porcelain properly without risk of movement, dipping, or cracking. 

What to check: 

• Soil Type: Heavy clay soils may need more drainage management; sandy soils may require extra compaction. 

• Ground Stability: Walk over the cleared area — if it feels spongy, soft, or uneven, deeper excavation or soil improvement may be necessary. 

Caledonian Stone Tip:
For particularly soft or unstable ground, consider laying a geotextile membrane beneath your sub-base to improve strength and prevent material migration.

3. Plan Effective Drainage

Why it matters:
Porcelain paving is practically impermeable. Without good drainage, rainwater can pool on the surface, creating safety risks and aesthetic issues. 

Best practices: 

• Create a Fall: Design your base so the patio slopes gently away from buildings (typically at a fall of 1:80 — about 12mm per metre). 

• Plan Outlets: Think ahead about where water will run to — whether that’s a garden border, a soakaway, or a drainage channel system. 

• Avoid Water Traps: Make sure the surrounding garden or features won’t cause water to sit against the paved area. 

Caledonian Stone Tip:
Use spirit levels or laser levels during ground preparation to set precise gradients from the start, rather than trying to adjust once slabs are down.

4. Build a Solid Sub-Base

Why it matters:
Porcelain paving is strong, but because it’s thinner and denser than natural stone, it demands a consistently even, fully supportive sub-base. 

How to do it: 

• Use Type 1 MOT Hardcore: Lay and compact in layers, no thicker than 75mm at a time, to build up the necessary depth. 

• Compact Thoroughly: A vibrating plate compactor is essential to achieve maximum solidity and eliminate air pockets. 

Depth Guide: 

• Light pedestrian areas: Minimum 100mm compacted hardcore 

• Driveways or heavy-use spaces: 150mm or more, depending on ground conditions (Always consult an experienced professional for this type of work) 

Common Mistake to Avoid:
Never lay porcelain paving directly onto bare soil or old, failing surfaces — it simply won’t last.

5. Final Levelling and Site Readiness

Before installation begins: 

• Check Levels: Use string lines stretched across the site to check that levels are consistent and falls are correctly set. 

• Fine Tune the Surface: If needed, add a thin layer of sharp sand or crushed fine aggregate to fine-tune surface regularity — but do not substitute this for a solid sub-base. 

• Prepare Edging Supports: If your design includes retaining edges or steps, install these first to lock the paving area securely. 

6. Double-Check Your Materials

Once your site is fully prepared, it’s time to get ready for the installation itself. Make sure you have: 

• Priming Slurry for the back of each porcelain slab (essential for strong adhesion). 

• Full-Bed Mortar Mix — not spot bedding. 

• Flexible Outdoor Grout designed for fine joints typical with porcelain paving. 

At Caledonian Stone, we can advise you on the best fixing products to suit your specific installation. 

Building the Perfect Foundation 

The truth is simple: careful preparation is the secret to a flawless, long-lasting porcelain patio. 

By taking the time to clear vegetation, manage drainage properly, create an even, compacted base, and plan your levels meticulously, you’ll set the stage for a space that stays stunning and stable year after year. 

Whether you’re working with a professional installer or taking on a DIY project, Caledonian Stone is here to support you at every step — from material selection to expert advice on creating a truly premium outdoor space. 

Ready to begin? Explore our outstanding porcelain paving collections or contact our team today for bespoke advice tailored to your dream garden.