HOW TO LAY A NATURAL STONE PATIO IN A RANDOM PATTERN WITH DAN SHAW | MPAC

Laying natural stone patio

Over the past couple of years we’ve worked with MPAC LTD on various natural stone patio construction projects and we love to chat stone with Dan and his team. If you’ve been following the blog you’ll have seen that we have recently had the opportunity to document a project we supplied for Dan in West Wellow, Hampshire. This was a 110m2 patio build using our Mint Sandstone in the random pattern featuring four sizes. It’s a very popular choice but one that some of our clients, having been used to paved areas that feature a tile in one size only, get confused over. This got us talking to Dan about how he approaches patio builds like this and the resulting interview and video below feature his thoughts.

Craig | Miles Stone:
Talk us through your initial stages of ground preparation when looking to build a patio area – how deep do you dig out the ground and what do you use to construct your base?

Dan | MPAC:
My rule-of-thumb is to dig out at least 150mm of ground, sometimes 250mm depending on the stone you’re laying and the property. Soil or poorly prepared bases need to be removed ideally. If there are slabs already laid that are being replaced I would always remove those completely so I could inspect the sub-base underneath and decide whether that will also need replacing. Once the dig out is complete I would lay 100-150mm of compacted Type 1 scalpings – this gives a solid base for foot-traffic. On top of this prepared base I allow around 30mm for mortar mix which the slabs will be laid onto.

Craig | Miles Stone:
What’s your mix ratio for mortar?

Dan | MPAC:
I work on a 5 parts sand to 1 part cement and add a little Febmix with the water to make the mortar smoother and easier to work with. You can use either sharp sand or building sand for this – they both go off hard.

Craig | Miles Stone:
And you recommend a full mortar mix rather than dot and dab?

Dan | MPAC:
I always use a full mortar bed yeah. Dot and dab is a thing of the past really. With a full mortar bed you know that 100% of the slab is supported by what’s underneath. A full bed also helps not to waste pointing mix too. If you have voids under the paving the pointing mixture can find it’s way into them and you are using a hell of a lot of pointing mixture just to get a fully supported paving join. A full bed allows the pointing mix to be fully supported and will make it a lot stronger.

Craig | Miles Stone:
A lot of customers come to us attracted to the variations and patterns you can create with a natural stone patio however they get a little fazed with how to lay these multi-size paving areas. Many of our clients feel they have to use a fixed ‘laying pattern’ rather than laying the stone truly random. What are your thoughts on laying patterns and how do you approach paving jobs like this?

Dan | MPAC:
I’ve never once used a pattern! I mean, there’s four sizes with this type of paving and as long as you avoid all four corners meeting (cross joints) and any long lines you can’t really go wrong. Aesthetically this type of paving always looks best if the joins are ‘T’ shapes rather than ‘+’ shapes. In my company I always tell the guys that all paving junctions need to be T joints. As I’ve said the other rule to follow is to try not to have any long lines. As you lay you may get a line that goes straight for 3-5 slabs, at this point you need to be thinking how you can block that line off to create a ‘T’ joint. With this in mind the slabs you have already laid dictate the next one – they tell you what it can be and what it can’t be. The other thing to be mindful of is that you use a fairly even mix of all the sizes as you work. If you lay this way then you generally never create the same pattern twice. I tell my clients that they are getting a bespoke patio.

Craig | Miles Stone:
Talk us through your process with pointing a patio – what mix do you use and what is your method?

Dan | MPAC:
I prefer to use a traditional building sand and cement mixture rather than the new all-weather pointing compounds a lot of people use these days. This is largely due to the smoother finish you can achieve. I use a damp sand and cement mix, fill the paving gaps and use a trowel tool to smooth off the mixture to create a trough type shape. Let the mix harden for a few hours and then sweep off the excess pointing mix. With this method you should be left with pointing joins that will hopefully last as long as the paving itself.

Craig | Miles Stone:
Natural stone obviously varies, sometimes hugely, from slab to slab how do you deal with that when constructing a patio area?

Dan | MPAC:
We actually have a grading system for assessing natural stone as we pull it out of the crates. The best looking tiles that are flat and straight would be labelled ‘A’s. These would get laid in the prominent areas of the patio where the client would see them often. Places where they are planning to have a table and chairs or immediately outside a set of doors for example. Tiles that aren’t quite perfect are grade ‘B’ and these would be used around the ‘A’ slabs. The slabs that have bigger highs and lows or dips (this is natural paving so these dips and shapes are unavoidable) would be graded ‘C’ and used for areas that are away from the main terraces, on footpaths or the slabs could be ear-marked for sections that require cuts.