A garden floor in this country gets tested in a way an indoor floor never does. Rain for most of the year, frost that arrives overnight in February, algae in the shaded corner behind the shed, and a barbecue that drips fat onto the surface in July. Most patio materials cope with one or two of those. Porcelain garden tiles cope with all of them, but only if you buy the right specification, and the spec is where most people get caught out.
Axar Tiles has supplied indoor and outdoor porcelain across the UK for over a decade, and the outdoor range is built around one format: 600 x 900mm, 20mm thick, matt finish. This guide explains why that combination works in a British garden and what to check before you order.
Why Porcelain Garden Tiles Survive UK Frost
Water is only a problem when it gets inside the material and then freezes. Freezing water expands by roughly nine percent, and if it has soaked into a porous slab, that expansion pushes the surface apart from the inside. Repeat the cycle across a winter and you get spalling, flaking and hairline cracks.
Full-bodied porcelain is fired at high temperature until the clay body vitrifies, which leaves a water absorption figure of 0.5 percent or less. There is almost nothing for the frost to work with. That is why the same material is used on balconies in the Alps and roof terraces in Manchester. Frost resistance is measured under BS EN ISO 10545-12, so ask any supplier whether the range you are looking at has been tested to it.
Compare that with the alternatives. Indian sandstone drinks water and needs sealing every couple of years. Limestone is softer again and marks where a plant pot sits. Concrete slabs are cheap and fine for a few seasons, then they fade unevenly and grow moss in the pores. Timber decking looks lovely in year one and needs treating, and it turns into an ice rink after rain.
The 20mm rule For Garden Flooring
Indoor floor tiles run 8 to 10mm thick. Outdoor porcelain is made at 20mm, and the difference is structural rather than cosmetic. A 20mm slab carries point loads from furniture legs, hot tubs and wheelbarrows, and it can be laid on a mortar bed, on gravel, or on adjustable pedestals over a flat roof.
The 600 x 900mm format used across the Axar outdoor range is worth understanding in practical terms. Each tile covers 0.54 square metres, so you need roughly 1.85 tiles per square metre. A 25 square metre patio takes about 47 tiles before wastage. Larger tiles also mean fewer joints, which matters because joints are where weeds and moss establish themselves first.
One thing to check on any large-format tile is edge treatment. Rectified tiles are cut to a precise size after firing, so joints stay consistent across a long run. Non-rectified tiles vary slightly and need a wider joint to absorb the difference. Neither is wrong, but the laying approach changes.
Stone Effect and Wood Effect Outdoor Tiles For a UK Garden
Search behaviour splits fairly evenly between people typing outdoor tiles for garden and people typing garden tiles outdoors, and both groups usually arrive wanting one of two looks.
Stone effect outdoor tiles are the more popular choice in UK gardens because they sit comfortably next to brick, render and planting without dating. The Axar outdoor range covers this with Crystal, Eclipse, Canyan, Forest, Desert, Gemstone and Lime Stone, in grey, anthracite, beige, ivory, white and tan. Grey dominates the range for a reason: it reads as neutral in flat British daylight, where warmer tones can look yellow under grey cloud.
Wood effect outdoor tiles give you the plank appearance without the annual sanding and staining that real decking demands. They work well for a raised deck area, a path running down a narrow garden, or a border around a lawn where you want the visual softness of timber and the behaviour of porcelain.
A third route is mixing both. Stone effect across the main seating area and wood effect for a walkway breaks up a long, narrow plot and stops a large expanse of exterior floor tiles from reading as a car park.
Slip Resistance On Outdoor Garden Tiles: R ratings and PTV
Wet porcelain outdoors needs texture. Two measures get quoted. R ratings run from R9 to R13 and come from a ramp test, with R11 the usual minimum for a domestic patio and R12 or R13 for pool surrounds and steps. The pendulum test gives a PTV figure, where 36 or above is treated as low slip potential in wet conditions.
Outdoor porcelain is normally supplied with a structured matt surface for this reason, and the whole Axar outdoor collection is matt rather than polished. Slip ratings are not currently published on every product page, so if a rating is a condition of the job, whether that is a rented property, a commercial terrace or a garden with a wheelchair user, request the technical datasheet before you order. Any reputable supplier can produce it.
Never put polished indoor porcelain outside. It will look superb for a fortnight and be genuinely dangerous by October.
How To Lay Porcelain Garden Tiles On a Patio
Most porcelain patio failures are installation failures, not material failures.
The base does the work. Standard practice is a compacted sub-base of MOT Type 1 at 100 to 150mm for a patio, more if vehicles will cross it. Above that goes a full mortar bed of around 35 to 40mm, mixed roughly four parts sharp sand to one part cement, at a semi-dry consistency.
Porcelain has almost no porosity, which is exactly why it survives frost and also why mortar struggles to grip it. A slurry primer brushed onto the back of each tile immediately before it goes down solves this. Skipping that step is the single most common cause of tiles drumming loose two winters later.
Then the details that decide whether the patio still looks right in five years:
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Lay a fall of about 1:80 away from the house so water runs off rather than sitting in puddles.
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Finish the surface at least 150mm below the damp proof course.
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Use joints of at least 5mm and grout with a proper exterior brush-in jointing compound rather than standard indoor grout.
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Support every tile fully. Dot and dab leaves voids, and a void under a 20mm slab is a crack waiting for someone to drop a plant pot.
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Cut with a diamond blade and take your time. Porcelain is hard, and rushed cuts chip.
If you are laying over a balcony, terrace or flat roof, adjustable pedestals are usually the better route. They lift the tiles clear of the membrane, allow drainage underneath, and can be lifted again if the roof needs attention.
Porcelain Garden Tiles Cost Per Square Metre
Outdoor tiles for garden projects are priced per square metre rather than per tile, which makes the sums straightforward. Tiles in the Axar outdoor range currently sit between £21.60 and £23.40 per square metre. For that 25 square metre patio, allow around 28 square metres of material once you have added 10 percent for cuts and breakage, or 15 percent if you are laying diagonally or in a herringbone pattern. Order the whole quantity in one go, because shade varies between production batches and a top-up delivery six weeks later rarely matches.
Delivery is free on orders over £500, which most full patios will pass, and returns run to 100 days.
Installation is the larger number. Expect labour and materials for the base to exceed the cost of the tiles on most jobs, particularly where an old patio has to come up first. That is the honest picture, and it is worth budgeting for properly rather than discovering it halfway through.
Cleaning and maintaining porcelain garden flooring
Exterior floor tiles take more abuse than anything you lay indoors, and this is where porcelain earns its keep. Maintenance is close to nothing, which is the main reason people move to porcelain garden flooring in the first place. Brush the surface, wash it down with warm water and a mild detergent a couple of times a year, and clear leaves out of the joints in autumn before they rot and feed moss.
No sealing is required. Nothing penetrates the surface, so wine, barbecue fat, bird mess and tree sap all wash off rather than staining. A pressure washer can be used at a sensible distance, though it is worth keeping the lance away from the joints so you do not blow the pointing out.
Colour holds too. Porcelain pigment is fired through the body rather than painted on, so the surface will not bleach out the way concrete does after a few summers.
Frequently asked questions
Are porcelain garden tiles suitable for UK frost?
Yes. Outdoor porcelain has a water absorption rate of 0.5 percent or lower, so there is very little moisture inside the tile to freeze and expand. Look for a range tested for frost resistance to BS EN ISO 10545-12, and make sure the tiles are laid on a full mortar bed with a fall so water drains away instead of pooling.
How thick should garden tiles be?
Outdoor porcelain is normally 20mm, which is roughly double the thickness of an indoor floor tile. The extra thickness carries furniture, planters and foot traffic without support underneath every point, and it allows the tiles to be laid on gravel or pedestals as well as on mortar. Indoor tiles at 8 to 10mm should not be used outside.
Are porcelain garden tiles slippery when wet?
Outdoor porcelain is supplied with a structured matt finish designed for wet conditions, unlike polished indoor tiles. For a domestic patio, R11 is the usual minimum slip rating, and a pendulum value of 36 or above is treated as low slip potential. Ask your supplier for the technical datasheet if a specific rating is required for the project.
Can I lay porcelain tiles on top of my existing patio?
Sometimes, but only if the existing surface is sound, stable, free-draining and laid to a fall, and only if the extra height does not bring the finished level within 150mm of the damp proof course. In most cases lifting the old surface and building a proper sub-base gives a better long-term result.
How many 600 x 900mm tiles do I need per square metre?
Each 600 x 900mm tile covers 0.54 square metres, so one square metre takes about 1.85 tiles. Add 10 percent extra for cuts and breakage on a straight layout, or 15 percent for diagonal and herringbone patterns, and order everything in a single batch to keep shading consistent.
Do porcelain garden tiles need sealing?
No. Sealing exists to stop liquid soaking into porous materials such as sandstone and limestone. Porcelain is vitrified and effectively non-porous, so sealant has nothing to soak into. The jointing compound between tiles is the part that benefits from being kept clean and intact.
Should I choose stone effect or wood effect outdoor tiles?
Stone effect outdoor tiles suit most UK gardens because they sit naturally against brick, render and planting, and grey tones stay neutral in overcast light. Wood effect outdoor tiles give the look of decking with none of the annual treatment, and they work particularly well on paths and raised areas. There is no rule against combining the two in one garden.
How much do porcelain garden tiles cost?
Material prices in the Axar outdoor collection currently range from £21.60 to £23.40 per square metre. Installation is typically the bigger cost, covering excavation, sub-base, mortar and labour, so budget for the full build rather than the tiles alone. Delivery is free on orders over £500.
Ready to plan your Garden Floor?
Work out your area, add 10 percent, then browse the Axar Tiles outdoor collection to see the full 600 x 900mm range in grey, anthracite, beige, ivory, white and tan. Free delivery applies over £500, returns run to 100 days, and if you want the technical datasheet for a specific range before committing, message the team on WhatsApp or call 0203 355 1197 and ask.
