
Outdoor spaces have become one of the most significant areas of home investment in the UK. Whether you are redesigning a patio, laying a terrace, finishing a pool surround, or creating a seamless flow from kitchen to garden, the material you choose for your outdoor floor will define how that space looks, feels, and performs for decades. Get it right and you have a space you genuinely use and love year-round. Get it wrong and you are dealing with cracked slabs, slippery surfaces, and persistent staining from the first winter onwards.
At La Fabrico in Exeter, we supply the complete Grespania Coverlam 20mm outdoor tile range, widely regarded as the finest outdoor porcelain tile available in the UK. This guide explains what to look for in an outdoor tile, how to plan your project, and why Coverlam 20mm consistently outperforms every alternative across every measure that matters.
Step 01
Understand why outdoor tiles are different
An outdoor tile faces challenges that no indoor tile ever encounters. Before thinking about aesthetics, it helps to understand exactly what your chosen tile needs to withstand in a UK outdoor environment:
- Frost and freeze-thaw cycles. UK winters subject outdoor surfaces to repeated cycles of freezing and thawing. Any tile with even slight porosity will absorb water, which then expands as it freezes, cracking the tile from within. Only tiles with near-zero water absorption are truly frost-proof.
- Sustained rain and surface water. A wet outdoor tile is a slip hazard. Outdoor tiles need a meaningful slip rating: a minimum of R11 for most patio and terrace applications, R12 around pool surrounds and on sloped surfaces.
- UV exposure and colour fading. Prolonged sunlight degrades many materials, causing colour shift and surface degradation over time. Outdoor tiles must be UV-stable to retain their appearance across years of sun exposure.
- Heavy loads and impact. Garden furniture, plant pots, foot traffic, and vehicles all place demands on outdoor surfaces. The tile must be thick and dense enough to bear these loads without cracking or chipping.
- Thermal shock. Outdoor surfaces move from extreme cold to direct summer sun and back again. A tile that cannot handle rapid temperature change will stress and crack over time.
- Algae, moss, and organic growth. A porous or textured surface in a damp UK climate is vulnerable to organic buildup that makes the surface slippery and unsightly. The right tile resists this at a material level, not just through periodic treatment.
A tile that passes all six of those tests is not a standard porcelain tile. It is a specifically engineered outdoor format, and that is precisely what the Coverlam 20mm range from Grespania was designed to be.
Step 02
Why Grespania Coverlam 20mm is the outdoor tile of choice
Grespania has been producing technical porcelain tile for over 40 years, and Coverlam represents the pinnacle of that expertise. The 20mm outdoor format takes the core Coverlam sintered stone technology and engineers it specifically for the most demanding outdoor applications. Here is what sets it apart:
Genuinely frost-proof
Coverlam 20mm has a water absorption rate of less than 0.5%, which qualifies it as BIa class: the highest porcelain density classification. With virtually no porosity, there is nothing for water to penetrate, and therefore nothing to freeze and expand. It will not crack in a UK winter, regardless of how severe.
R11 slip resistance as standard
Every tile in the Coverlam 20mm outdoor range meets the R11 slip rating as a minimum standard, with many collections achieving R12. This is the recognised minimum for safe outdoor use in the UK and Europe, providing reliable grip underfoot in wet, icy, or leaf-covered conditions year-round.
UV-stable: will not fade
Unlike natural stone, timber, composite decking, and many lesser porcelain tiles, Coverlam is completely unaffected by UV radiation. The colour you choose on day one is the colour you will still have in fifteen years. No bleaching, no fading, no need for UV-protective treatments or coatings.
20mm thickness for structural strength
At 20mm thick, Coverlam outdoor tiles have significantly greater load-bearing capacity than standard indoor formats. They can be laid on a prepared bed without any concern about cracking under heavy garden furniture, planters, or foot traffic, including wheeled loads such as bicycles and garden equipment.
Thermal shock resistance
Coverlam is manufactured using a sintered stone process that fires raw materials at extremely high temperatures, producing a tile that is dimensionally stable across a vast temperature range. It handles the shift from a frozen January morning to direct August sun without warping, cracking, or delaminating.
Hygienic and chemical-resistant
The near-zero porosity that makes Coverlam frost-proof also makes it resistant to staining, mould, algae, and chemical attack. Moss and algae cannot take hold in the tile surface itself. A pressure wash or simple scrub is all it takes to keep a Coverlam outdoor surface looking pristine.
Sizes up to 3.6m x 1.2m
Coverlam is produced in the largest tile formats available in the UK, including slabs up to 3.6 metres long. For outdoor spaces, this means genuinely seamless surfaces with almost no grout joints: the outdoor equivalent of the most sophisticated interior tile drenching. La Fabrico is one of very few showrooms in the country to stock the full format range.
Seamless indoor-outdoor flow
Coverlam’s 20mm outdoor range shares design families with the Coverlam indoor collection. The same stone-effect, concrete-effect, and wood-effect designs are available in both an indoor and an outdoor specification, making it possible to run the same tile from inside the kitchen or living room across the threshold and out onto the patio without any visual break.
A Coverlam outdoor tile does not require sealing, treating, oiling, or annual maintenance of any kind. Lay it once and it performs at the same level on day one as it does a decade later. That is not something any natural stone, timber, or composite decking product can match.
Step 03
How Coverlam compares to the alternatives
When planning an outdoor space, most homeowners consider several materials. Here is how Coverlam 20mm measures up against the most common alternatives across every factor that matters in a UK setting:
| Material | Frost-proof | Slip resistance | Fading / UV | Maintenance | Longevity |
|---|---|---|---|---|---|
| Coverlam 20mm porcelain | Yes — BIa class | R11 / R12 standard | No fading: UV-stable | None beyond cleaning | 50+ years |
| Natural stone (sandstone, limestone) | Varies — requires sealing | Moderate, varies by surface | Can fade and stain over time | Annual sealing required | 20–40 years with care |
| Timber decking | No — can split in frost | Low when wet, slippery | Greying, bleaching without treatment | Annual oiling or staining | 10–20 years |
| Composite decking | Generally yes | Moderate when wet | Some fading over time | Periodic cleaning, some retreatment | 15–25 years |
| Concrete / resin paving | Generally yes | Moderate — can become slippery | Can stain and discolour | Periodic treatment | 20–30 years |
| Standard porcelain paving | Yes if low porosity | R10–R11 typically | Generally stable | Low | 30–50 years |
When comparing outdoor materials, always ask for the tile’s water absorption rating alongside its slip rating. Water absorption below 0.5% (BIa class) is the standard you need for a genuinely frost-proof outdoor tile in the UK. Many tiles marketed as “outdoor suitable” do not meet this threshold.
Step 04
Choose the right outdoor application
Coverlam 20mm is engineered for versatility. Here is how it performs across the most common outdoor applications in UK homes:
- Patios and terraces. The most common application. Large format Coverlam tiles on a patio create a surface that looks far more sophisticated than any traditional paving slab, requires no maintenance beyond an occasional clean, and will outlast every timber or composite deck alternative. Choose a stone-effect or concrete-effect tile for a contemporary result, or a wood-effect plank for warmth.
- Seamless indoor-outdoor flow. One of the most sought-after results in contemporary home design: the same tile running from inside a kitchen or living room across a threshold and out onto the terrace. With Coverlam, this is genuinely achievable. Use a Coverlam indoor tile in the relevant room (5.6mm or 12mm format) and the matching Coverlam 20mm outdoor tile on the terrace. The tile design is identical; only the thickness and surface specification change.
- Pool surrounds. The area around a swimming pool is one of the most demanding outdoor environments: constantly wet, high-traffic, and completely exposed to UV. Coverlam 20mm with an R12 slip rating is the correct specification for pool surrounds. Its hygienic, non-porous surface also resists chlorine and pool chemicals without degradation.
- Steps and raised areas. Coverlam 20mm can be used for external steps, with purpose-made stair nosing pieces available in matching designs. The thick format provides the structural strength required for step edges, which take considerably more impact than flat paving.
- Raised decks and pedestal systems. Many Coverlam 20mm formats are suitable for installation on pedestal systems, which raise the tile on adjustable supports above the structural slab below. This is ideal for roof terraces, balconies, and anywhere where drainage needs to run beneath the finished surface. No adhesive is required, making future access to the substrate straightforward.
- Driveways. Selected Coverlam 20mm formats are suitable for light vehicle traffic when installed on an appropriate sub-base. If you are considering a driveway application, our team can confirm which formats and collections are approved for vehicular loads.
Step 05
Choose your design: the Coverlam outdoor collections
One of the most compelling aspects of Coverlam 20mm is that choosing an outdoor tile no longer means choosing between performance and aesthetics. The Coverlam outdoor range offers the same design sophistication as the finest indoor tiles:
Stone and travertine effects
The most popular choice for UK outdoor spaces. Stone-effect Coverlam tiles in limestone, travertine, sandstone, and slate tones bring the look of natural paving with none of its maintenance demands. Particularly effective in larger formats where the minimal grout lines create a surface that reads as genuinely seamless. These designs work beautifully alongside natural planting and create a timelessly elegant terrace.
Concrete and micro-cement effects
For a more contemporary, architectural feel, concrete-effect Coverlam tiles deliver the industrial warmth of micro-cement without the porosity, cracking, or maintenance that poured concrete surfaces require outdoors. Available in a range of tones from warm greige through to cool anthracite. Particularly strong in modern garden rooms, roof terraces, and alongside contemporary architecture.
Wood-effect plank tiles
The Coverlam wood-effect outdoor range captures the warmth of timber decking with none of its practical shortcomings: no splitting, no greying, no annual oiling, and no slip hazard when wet. Available in natural oak, weathered grey, and warm walnut tones, and in plank formats that replicate the proportions of real deck boards. The ideal choice for anyone who loves the look of decking but has experienced its limitations first-hand.
Marble-effect and premium finishes
For pool surrounds, luxury terraces, and high-specification outdoor spaces, Coverlam marble-effect outdoor tiles bring genuinely dramatic visual impact to exterior surfaces. The combination of bold veining, large format, and minimal grout lines creates a pool surround or terrace that would look at home in a five-star hotel. UV stability means the colour and veining pattern will look identical in ten years’ time.
We hold the complete Coverlam 20mm outdoor range in our Exeter showroom, including large-format slab formats that most UK retailers do not stock. You can see every collection in a real outdoor display setting and take full-size samples home. Our team can also match your chosen Coverlam outdoor tile to its indoor equivalent for a seamless flow through from inside to outside.
Step 06
Plan your outdoor tile installation correctly
Coverlam 20mm performs to its full potential when it is installed correctly. These are the planning decisions that most affect the quality and longevity of the finished result:
- Start with the right sub-base. Outdoor porcelain tiles must be laid on a stable, well-compacted sub-base. For most patio applications, this means a minimum 100mm compacted hardcore base topped with a concrete bed or sharp sand and cement. A poorly prepared sub-base is the single most common cause of outdoor tile failure: even the strongest tile will crack if it is bridging voids or soft spots beneath it.
- Use a full-bed adhesive method. Large format outdoor tiles must be fixed with full coverage of adhesive on both the tile back and the substrate — the full-bed method. Any hollow spots beneath a large tile will concentrate stress and cause cracking under load. Your installer should use a notched trowel on both surfaces and back-butter every tile.
- Allow for correct falls. Any outdoor surface needs a fall of at least 1:80 (ideally 1:60) away from buildings and towards drainage points. Water that pools on an outdoor surface will accelerate any joint or surface degradation and create persistent slip hazards. Your installer should set falls correctly before a single tile is laid.
- Use outdoor-rated grout and pointing. Standard interior grout is not suitable for outdoor use. Use a flexible, frost-proof pointing compound specifically rated for external applications. This accommodates the slight thermal movement that occurs in outdoor surfaces without cracking at the joints. Joints should be a minimum of 3mm for outdoor porcelain.
- Include perimeter and movement joints. Outdoor tiled surfaces expand and contract seasonally. Movement joints filled with a flexible silicone or pointing compound should be installed at all fixed perimeters (against walls, steps, and fixed structures) and at intervals of no more than 3 to 4 metres across large areas. An experienced outdoor tiler will plan these from the outset.
- Commission an experienced outdoor tile installer. Large format outdoor porcelain is a specialist installation. Not all tilers have experience with 20mm formats, pedestal systems, or the specific adhesive and jointing products required. Ask your installer specifically about their experience with large format outdoor porcelain before appointing them. Our team at La Fabrico can recommend trusted installers across Devon and the South West.
Using an indoor tile outdoors. This happens more often than you might expect, particularly with porcelain tiles that look similar in both formats. An indoor tile lacks the slip rating, frost resistance, and thickness to perform safely outdoors. Always confirm that any tile specified for outdoor use carries an R11 or higher slip rating and a water absorption of under 0.5%. If it does not have both of these, it should not go outside.
Step 07
Order the right quantity
Ordering correctly for an outdoor project is particularly important because outdoor spaces often have irregular shapes, steps, and drainage channels that generate more cuts than a typical indoor room:
- Allow 15% above your measured area as a minimum for a straightforward rectangular patio. For irregular shapes, steps, or any layout with a pattern or directional design, allow 20%
- Order everything from the same batch. Tile colour varies between production runs. Running out and reordering from a different batch means a visible colour difference in the finished surface. Check the lot number on every box when your order arrives
- Keep spare tiles from your original batch. Store at least four or five tiles after installation. Outdoor tiles can be damaged by dropped tools, heavy garden equipment, or impact. Having a spare from the correct batch makes any repair invisible
- Our team will calculate your quantities precisely. Bring your garden dimensions, a rough sketch, and any photos of the space to our Exeter showroom and we will work out exactly how much tile, adhesive, grout, and pointing compound you need before you commit to an order
See the Coverlam outdoor range in our Exeter showroom
We are one of the UK’s only stockists of the full Grespania Coverlam outdoor collection, including large format slabs up to 3.6m x 1.2m. Visit our showroom in Exeter to see every collection in real outdoor displays, take full-size samples home, and speak to our team about your project. We can calculate quantities, recommend installers, and match your outdoor tile to its indoor equivalent for a seamless flow. Guaranteed Best Prices.
lafabrico.com | 01392 848487 | Marsh Barton, Exeter EX2 8QX



