Indoor-outdoor matching porcelain tiles and paving slabs are becoming more common, but be aware these are two different products with different specifications and surface finishes. Exterior porcelain has to be suitable and have an R11 anti-slip rating to be considered safe for exterior use (where surfaces will be wet), so anti-slip technology measures needed to counter this must be used. When selecting matching interior and exterior tiles and pavers, review the anti-slip ratings:
There are plenty of options when it comes to paving slab sizes, ranging from 100 x 100 mm right up to 2000 x 2000 mm to suit any preference.
The inherent strength of the material will determine how large you can make the paving slab. The stronger it is, the bigger the slab’s lengths and widths can be relative to its thickness.
Concrete slabs – rarely larger than 900 x 600 mm as the material is not strong enough (and these larger ones will tend to be pressed slabs with a 50 mm depth). With concrete, 600 x 600 mm is considered large.
Natural stone slabs – you’ll find a reasonable selection of sizes, ranging from 100 x 100 mm to 900 x 600 mm (and even 1200 x 600 mm in some cases, although these are rare).
Porcelain slabs – offers the widest range of possible paving slab sizes. This material is strong enough to support sizes of up to 2000 x 2000 mm, although 900 x 600 mm and 1000 x 500 mm are the most common sizes. Porcelain setts (100 x 100 mm and 200 x 100 mm) now becoming an industry standard too.
When it comes to picking out the right patio paving pattern, you first need to decide whether to go for a uniform, single-size format or mixed-size paving (with a selection of squares and rectangles):
If you’d like to create a consistent laying pattern, go for single-size slabs. A wider variety of patterns is sometimes possible with mixed-size slabs, although you’ll need to consult the laying patterns first.
All three types of patio paving material are available as single-size formats or as mixed-size. That said, mixed-size slabs are much less prevalent with porcelain paving at present, and you’ll most likely only encounter single size packs.
Below we’re placed single size paving next to a mixed size patio so you can see the difference between the uniform pattern of the former and the more irregular pattern of the latter.
Your choice of jointing style will also affect the appearance of your patio paving pattern. For a contemporary aesthetic, you may want to consider narrow-jointed paving (where the slabs are positioned close together). On the other hand, wide-jointed paving tends to offer a more traditional look.
All three types of paving can be narrow-jointed (contemporary) or wide-jointed (traditional), but narrow-jointing will require the paving to have a straight or sawn edge that’s not chamfered, so the slabs can be laid near together (3-5 mm).
A jointing compound is recommended for concrete and stone installations. Exterior paving grout is recommended for porcelain paving. However, a jointing compound can be used with porcelain, and will look okay if you’re using a traditional joint width.
As you consider which pattern and jointing to go for, remember that the material you choose will impact the options that are open to you:
Concrete paving – The edge profile of decorative concrete typically lends itself to wide jointing (the more traditional style). Pressed concrete will often have straight edges, and can be jointed narrower. Concrete slabs come in a wide range of size formats, with mixed size packs being common, giving you lots of choice when it comes to laying patterns.
Natural stone – With plenty of size formats available, stone offers flexibility in terms of laying patterns. You can also choose between hand-cut chamfered edges or straight sawn edges, depending on whether you’d prefer contemporary narrow or standard and traditional wider jointing.
Porcelain paving – Mostly sold in single-size packs, with limited options when it comes to mixed-size packs. If you choose this material, you’ll likely have to go for a more uniform paving pattern (or do a lot of cutting!).
The cost of patio paving is not merely reflected in the price-per-metre-square of the slabs themselves. That is only one element amongst many which will determine what you end up paying. The main thing to factor in when buying patio paving is the installation costs (more on this below).
Historically, concrete paving was the cheapest option. Then global trade allowed low-cost importation of natural stone from the likes of China and India, creating a large market in the last 30 years for the likes of Indian sandstone in the UK. Recent disruption to the global supply chain from Covid-19 has seen natural stone prices rise again, as shipping costs increase dramatically. This has equalised prices, bringing all three types of paving into a closer range.
PHOENIX PAVERS ARIZONAIt’s important to check carefully when comparing paving from different suppliers, as not all slabs are of equal quality. Here, we’ve provided some top tips to help you shop wisely:
You typically get what you pay for because paving is made and supplied to a price within market conditions. A cheaper price is often a sign that the slabs are either of a lower quality or have fewer processes involved in their production.
If the price of natural stone paving seems too good to be true, this is often because it has been sourced from lower quality quarries or taken from shallower seams of rock. It may look the same as sound stone to begin with, but will likely see more delamination, abrasions and cracking over time.
Sawn edges, honed surfaces, tumbled ageing and depth calibration of natural stone all add to the cost. Expect to pay more for processed natural stone paving.
Concrete and porcelain paving is man-made – below-average prices are often the result of cost-saving in the manufacturing process, which produces lower quality slabs.
The main cost of a new patio is the installation (materials and labour). The paving slabs will rarely be more than 20% of your total costs. Even if you end up spending double on the slabs, the impact on the cost would typically only add 10% to the project.
The key to keeping costs down is finding a good installer with a proven track record. Pay a little more to get the right installer – it will probably save you money as there will be no mishaps or errors to put right, and experts tend to work efficiently to their schedule too.
The key to keeping costs down is finding a good installer with a proven track record. Pay a little more to get the right installer – it will probably save you money as there will be no mishaps or errors to put right, and experts tend to work efficiently to their schedule too.
Natural stone is the easiest material to cut and lay, with large slabs and few breakages. As a result, the installation should be quicker, keeping your costs down.
Porcelain is much more difficult to cut, adding to your installation time and costs. That said, it is a tough material so breakages should still be few and far between.
Concrete has more potential for breakages and often comes in smaller slabs, meaning it could take a little longer to cut and lay. Installation costs for concrete paving should be roughly the same as porcelain, but will often be more than natural stone for the same area of paving.
Each different type of paving slab material has unique properties that affect the likelihood of it fading in the sun, weathering due to slightly acidic rain or eroding as a result of freeze-thaw cycles:
Concrete is the least long-lasting paving material. With high porosity and weaker slab strength, concrete can crack more easily than other types (although you can help to prevent this by sealing the paving slabs).
Natural stone tends to be more durable than concrete. That said, limestone can be susceptible to chemical erosion from rain and UV bleaching, whilst the surface of sandstone can delaminate (i.e. divide into layers) as a result of frost action.
Porcelain is particularly hard-wearing and will typically last for a very long time. This material is not only waterproof and frost-resistant, but its pigments are also UV-protected to prevent fading.
We recommend sealing less durable paving materials such as concrete, limestone, and sandstone. This will help to protect them against the elements, reduce the likelihood of moisture related staining and frost action, and extend the lifespan of your patio paving.
Maintenance requirements are an often-overlooked consideration when choosing patio paving. The porosity and hardness of the paving material will determine how easy or difficult it will be to maintain whilst preventing stains, scratches and the build-up of grime.