Earlier this year a customer from St Albans was in touch about their Sandstone patio which as you can see was looking neglected and worse for wear. The forecast was for a heat wave and so they were keen to get the patio cleaned up and available for use.
We are based in St Albans so it wasn’t long before I was able to pop over survey the stone and discuss its renovation. It turns out the patio was laid 10-12 years ago but over that time the original grouting had slowly broke down resulting in weeds growing up and around the stone, black mould spots had also begun to appear.
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I worked out a price for the cleaning and sealing the sandstone including replacing the pointing with a modern durable resin-based product that is more resilient than sand and cement that was used before. I was confident the job would be completed in a day and after accepting the quote a date was set for our return, dependant on the weather.
Deep Cleaning a Sandstone Patio in St Albans
Rain as it turned out was not a concern as we had weeks of dry weather, some very high temperatures and a drought declared. The bigger concern was ensuring the team remained hydrated during the work which makes a change.
Work started with the removal of all the old grouting and deep routed weeds. Much of the grout was already cracked and loose so came out very easily, the rest had to be raked out or carefully chipped out with a chisel. Care was taken not to mark the paving and the whole lot then swept into a pile and bagged up for disposal. Once the grout had been removed a weed killer was sprayed into the gaps.
Next the Sandstone patio was sprayed with Tile Doctor Pro-Clean and left to soak into the stone for a good ten minutes. The patio was then scrubbed in with a black pad fitted to a rotary machine. Once the whole patio was cleaned in this fashion it was rinsed off with a hose and extracted with a wet vacuum where possible.
The next step was to deal with the Black Spots by applying a specialist cleaning product decanted into a low-pressure spray bottle. This is sprayed onto to stone where it impregnates the sandstone and breaks down the staining. The product needs to be left on for a long time for best results and then once the black spot has disappeared the patio is rinsed with water.
Sealing a Sandstone Patio in St Albans
The patio was left to dry off overnight which given the high temperatures we were experiencing at the time probably didn’t take long. It was certainly dry by the next morning.
To bring out the natural colours in the Sandstone it was then sealed with Tile Doctor Colour Grow which is an impregnating sealer. Impregnators soak into the stone occupying the pores and ensuring dirt and liquids remain on the surface where they can be easily rinsed away.
The last step was to repoint the stone using a buff-coloured resin bonded pointing compound that matched well with the patio. This completed the renovation and ensured the patio was completely sealed and any water would run off.
The job took two Tile Doctor technicians two days to complete and I think you will agree they managed to completely transform the patio which now looks like a new installation.
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For aftercare its worth remembering that the stone has been sealed so it’s important to use a neutral ph cleaning product such as Tile Doctor Neutral Tile Cleaner that won’t damage the sealer. Anything stronger will erode the sealer over time prematurely removing the protection it provides.
Source: Sandstone Patio Cleaning and Restoration Service in St Albans Hertfordshire
Based in St Albans, Robert Voyce is an expert in tile, stone, and grout maintenance. As a trusted agent of Tile Doctor—the UK’s largest professional tile, stone, and grout restoration network, Robert has access to specialist products and proven techniques to tackle a wide range of cleaning and restoration challenges. Whether interior or exterior, domestic or commercial, you can rely on expert care and outstanding results.