This increasingly popular choice of sandstone paving gained popularity around a decade ago. A quick look up and down your street and the chances are you will spot a handful of properties with these slabs installed in their front gardens.
Read on and learn how sandstone paving became a favourite patio surface in the UK.
The History of Sandstone Paving
There are several reasons for the increase in popularity ranging from the colours, the price or simply the availability UK wide.
As people grew to care about how their outdoor spaces look, people started to use concrete paving slabs to create patio areas and other features to make their garden pop.
These concrete slabs were easy to produce en masse, easy to regulate in terms of size and thickness and much more affordable than the alternatives at the time.
The only alternative was British quarried stone, which was at least double the price, irregular thicknesses and incredibly laborious to lay. Creating concrete slabs became a really strong process delivering great results – around 30 years ago.
The concrete slabs could be made up of so many textures and styles that you would struggle to tell the difference between them and the genuine article unless you had a really keen eye for it.
Then suddenly, a global supply of sandstone began to reach the UK shores and natural stone paving was finally affordable to many who couldn’t afford the York stone that was so sought after.
The price of using a genuine stone paver to complete an outdoor space halved overnight in some cases. All of a sudden, you had masses of stone slabs arriving from India, China, Brazil – you name it – which were half the price of British York stone, cut in regular sizes and arriving in a beautiful array of colours.
The demand for such a product, which seemed lukewarm at best before this, sky-rocketed as people jumped at the chance to get a stylish, genuine stone patio at prices that were genuinely affordable.
Sandstone As The Paving Product
A majority of the sandstone paving slabs that you see used in the UK comes from India.
Sandstone comes under a handful of different names depending on supplier. For example, Marshall’s have a ‘Riven Harena’ range that is simply imported Indian sandstone. Their ‘Silver Birch Multi’ is what is often called ‘Kandla Grey Sandstone’ for the majority.
There are quite a few different names from different suppliers, so just be aware that a fancy name does not necessarily mean that you are getting a superior product.
Merchants up and down the country stock varying qualities of the same stone but attempt to make it unique by jazzying up the name slightly.
It’s important to look into the quality and not be drawn in by what seems like a fancy name.
So many of these sandstone paving slabs are now readily available in most parts of the UK, with a handful of companies even happy to ship UK wide, that it’s important to make yourself aware of exactly what you are purchasing.
Even though you are purchasing a product of the same name, there can be a huge gulf in quality between slabs from different suppliers.
So it’s important to know how to do a quality check to your sandstone slabs.
Sandstone is made up of grains of sand held together by a silicon based ‘cement’. It’s this cement that gives the sandstone is various colours, textures and toughness.
The weaker this cementitious material is, the worse quality of the stone. The really poor-quality materials will be very weakly compacted and will noticeably fall apart simply by rubbing the stone between your fingers. This stuff will crumble and leave a sandy residue on your fingers.
This is a quick check you can do to rule out the bottom of the barrel stuff immediately! Although the quality of available sandstone has been increasing over the years, avoid merchants out there that offer poor quality materials.
Characteristics & Variations
Sandstone is a fantastic material to work with and as a result there are a whole bunch of variations and styles that you can get sandstone paving slabs in.
There are so many in fact, that you can get quite confused with it all, so it’s important to know just what the different things mean. You can get variations in:
- Edge Type
- Surface Finish
The first thing that it pays to be aware of is the different sizes that slabs themselves will come in. There are two common ranges of slabs that are available to purchase:
- The 60 series
- The 56 series
These ‘series’ are designed to be laid together with a common multiple so they can be laid fairly logically, minimizing the risk of there being an odd pattern.
In the depths of the supplier market, there are some that will sell boxes of straight-up quarry rejects in sizes like 760x590, 550x360 and 880x720 with seemingly no way to fit these together without a ton of cuts.
As a result, you may end up with paving that will look absolutely shocking anyway.
This is the first thing to look out for, anything but the above two size options should be binned off immediately unless working with a single size - then it doesn’t matter so much.
As for the difference between the two, the 60 series in our opinion is a slightly better option for everyone. The 56 series is normally made up of 5 different slab sizes, compared to the 4 different sizes of the 60 series.
The slabs within the 60 series cover more area per slab, meaning there is less labour involved in laying.
In the long run, it might save you a few quid per project, so if you are an industry professional it could add to £100s or even £1000s per year.
While the 56 series isn’t a terrible option – it’s certainly better than the random options that you can find out there – we would always recommend the 60 series as the better option.
This is the most significant contribution to the price/quality variation on the market is almost always the thickness of the slabs. There are a bunch of reasons for this:
Calibration is the most common reason that slabs will vary in price. Once quarried, there is an option to calibrate all slabs to the same thickness so they are easier to lay quickly as, in theory, the area will be much easier to keep level due to the regulated thickness of the slabs.
This will increase the price slightly from the raw quarried slabs but should earn itself back with the time that it saves in the process. Uncalibrated slabs will likely have a cheaper m2 price, so keep on eye out for this.
Another factor that can affect the costs of slabs is the UK shipping limits restricting how much can be packed into a box.
The limit is 1 tonne on almost all occasions and shipping prices are charged per box. The thicker the slab, the less you can pack into a box.
This results in a kind of balancing act between going for a thicker, sturdier slab but being stung with the extra delivery costs or getting thinner slabs and getting more packed into each box.
As a rough guide, you should expect approximately 15m2 per tonne of uncalibrated paving & 18m2 of calibrated paving per box, anything more is questionable.
This is a major factor in paving quality and cost. Often people make the mistake of not looking at the thickness of the slab they are purchasing and end up with a wildly inferior product for the sake of a £20 saving.
Down the years we have seen three main thicknesses appear for sale:
- 18mm-25mm – this is a common form of uncalibrated paving that seems to have appeared in the market more and more over the last few years. This is really the thinnest paving we could recommend without serious reservations. With the tolerance that you get, some slabs may arrive at nearly 15mm which is too thin for outdoor use in most instances. This is what we would call a budget option – you can get a patio area done and save yourself around £40 on a 20m2 job. You will normally get 18m2-20m2 of paving per 1 tonne box. Guide Price: £13.50+VAT per m2 + £45 per 18-20m2 box for delivery.
- 22mm Calibrated – This is the perfect option in our opinion. 20mm is the minimum you want to be working with outdoors – anything thinner and your risk it being exposed when the elements start to give it a battering of frost and rain. Going with a calibrated option not only makes it easier to lay, but means you get a good amount of paving per box and it’s guaranteed to be a thickness that will survive the elements. Guide Price: £16.00+VAT per m2 + £45 per 18m2 box for delivery.
- 25mm-35mm – This used to be more readily available than it is today. It’s a fantastic quality slab and certainly going to be the most robust because of the thickness, however you can only fit around 15m2 in a 1 tonne box, which means larger orders may get stung with really high delivery costs. The slabs themselves are often cheaper than the calibrated version, but it’s the delivery costs that will get you. Guide Price: £15.00+VAT per m2 + £45 per 15m2 box for delivery.
Because sandstone is so workable, there are all sorts of special finishes that can create subtle differences in a job that will really make it stand out.
The most common finishes are the different edge types. There are a few different names and styles which can make it quite confusing to know exactly what you are getting:
A Hand-Dressed Edge Slab
This is the ‘standard’ finish if you like. Most slabs which are being purchased are hand dressed.
This finish can also be known as:
- hand-finished or any number of things.
The most common abbreviations you will see are H/D or H/c. This edge is done with a hammer a chisel and the stones are chipped to size by hand.
This results in a rough edge that creates a natural effect. If you are looking for a balanced look to your area, this is the right choice.
Sawn-Edge Paving Slab
Guide Price: +£1.00 per m2 compared to H/D.
This style is increasing in popularity as the modern, contemporary look is comes more and more into fashion.
These slabs have gone through an additional process whereby the edges are completely sawn smooth to give square edges on all 4 edges.
These slabs can be known as clean cut edge, square edge, smooth edge slabs or any similar name.
They are perfect for matching in with a modern looking outdoor space as the clean edges of the slab add to the effect. They sit perfectly parallel and are a joy to lay.
Antique-Tumbled Paving Slab
Guide Price: +£1.00 per m2 compared to H/D
Whilst not as popular as it once was, this is unique style of paving which is perfect for creating an instantly aged feel.
Ordinarily, sandstone paving takes years to settle in to match in with an older property, but with tumbled edges they are aged to instantly match in.
The slabs have been through an extra process of tumbling to give the aged look – they are also occasionally known as antique edge slabs.
Make sure you check out some of other materials on the Primethorpe Paving blog.
Sandstone Paving - Surface Finishes
This is another area where there are an increasing number of variations, leading to lot of confusion about what exactly everything means.
There are words such as ‘leathered’, ‘riven’ and ‘flamed’ attached to slabs with little explanation with respect to what they mean. Hopefully we can shed some light!
This can affect the prices by a few pounds a meter, so it’s good to know what you are getting.
The most common form of surface finish as this is how the slabs come out of the ground. Riven means it has a natural textured surface and is rough and uneven to the touch.
There are different levels of riven-ness, but this is in the nature of the stone so only adds to the charm.
If a slab is overly riven, this can indicate it is perhaps to soft, but is normally nothing to be concerned about.
Sometimes referred to as 6-side-sawn, these are slabs that have a surface that is smooth to the touch. These have not been polished but cut out of a block in this way.
They are almost always calibrated and create a nice contemporary look. Guide Price: +£3.00 per m2 compared to riven.
Honed slab can be difficult to maintain but provides the ultimate contemporary look when it is laid. They are riven slabs that have been through a honing process which polishes the surface and makes them incredibly smooth.
These were popular amongst people creating a modern garden as they were incredibly uniform.
They take a bit of looking after due to the flawless surface. If they get damaged it is really noticeable. But if you look after the slabs, they can create a fantastic look. Guide Price: +£6.00-£10.00 per m2 compared to riven.
The final common sandstone paving finish is a sandblasted finish. When talking about sandblasted paving, it is often implied that the surface of the stone has also been brushed with a rotating brush head to finish.
The sandblasting adds an element of non-slip to the paving slabs that may have been overly smooth. The process dimples the surface to give an extra bit of grip.
The brushing process that comes after, softens the dimples in the stone so they don’t look so dramatic. Not only does it soften the texture, but it also softens the colour which results in beautifully blended colour palettes on the slabs.
Sandblasted paving is a top of the range sandstone and can look absolutely amazing when done properly. Guide Price: +£10-£16 per m2 compared to riven.
We hope this have given you some idea of how to make sure you are getting the best value for money when purchasing sandstone. It's a big decision, so it's important to get exactly the look and feel you require - first time!