
We’ve got three extensions on the go at the minute out towards Pinhoe and Broadclyst, and on every one of them the same question comes up towards the end of the job: what do we do with the patio or driveway once the extension’s finished? Tarmac have just launched Masterlay External, a self-levelling flooring compound aimed at exactly that, patios, driveways, garages and outbuildings, and it’s worth knowing about if you’re planning building work for next spring.
On a standard single-storey rear extension we’re still working to trench-fill or strip foundations depending on the ground, block and beam or a suspended slab where there’s any risk of movement, and a cavity wall tied back with stainless wall ties at the usual 450mm vertical spacing. None of that’s changed. What’s changed is what happens once the shell’s up and you’re finishing the ground around it.
A self-levelling external compound like this matters because so much of what goes wrong with a new patio or driveway isn’t the surface, it’s the prep underneath, inadequate falls, no proper DPC detail where the new slab meets the house, or a screed loaded before it’s had a chance to cure. Masterlay External is formulated to cope with exposure to the weather, which round here means something that’ll survive a Devon winter without cracking or lifting at the edges.
It matters for the smaller jobs too, loft and garage conversions where you’re left with an odd bit of ground outside a new external door, or a Help to Build project where the budget’s tight and you can’t afford to redo a driveway twice. Being able to spec one product for patios, garages and outbuildings alike simplifies the job and keeps costs down for the homeowner.
If you’re planning an extension, loft conversion or garage conversion around Exeter, Topsham, Exmouth or out towards Cranbrook, DMS Conversions can talk you through what’s involved from foundations through to the finishing details.


