New stone cleaning equipment company Restorative Techniques are offering a broad range of cleaning solutions that includes their own vortex abrasive technique and a superheated water cleaning system.

Although Restorative Techniques are new to the stone cleaning equipment supply business, Jamie Fairchild and his wife Julia, who set up the company, certainly aren’t.

Jamie has been directly involved in technical support for three decades, and with the treatment of historic buildings since 1987, although then it was only a sideline to his full-time job of designing and producing bespoke surfaces for military and civilian contracts including aircraft runways. When he was with Robert Hobbs, once one of the largest quarry owners in the country that was taken over by Wimpey Minerals, he even played a part in the creation of the road surfaces on the motorway of the new Severn Crossing.

He was a materials engineer and an expert in the analysis of crushed stone for concrete and asphalt surfaces and he admits his approach to stone cleaning, when he started to get involved in that, was much more related to the physical properties of stone and the materials to be removed from its surface than to its aesthetics.

He went into stone cleaning full-time in 1994, joining Julia’s family firm. Jamie and Julia decided to branch out on their own in 2009 and have developed their own versions of a vortex gentle abrasive cleaning system and a superheated water cleaning system.

They also offer a range of materials for removing unwanted coatings of applied finishes and the build up of carbon and other airborne pollutants, as well as stains left by copper and lead pipes and lightning conductors, for example. And they do not supply them only as finished products, but also as components for conservators to make up their own mixes.

Restorative Techniques, who are based near Bristol, only supply the products (they do not do the work themselves) but Jamie will happily help with specifications for cleaning projects.

With his technical background and practical experience in the industry, he has a wealth of knowledge about stone cleaning that he is happy to use to advise property owners and architects on the best way of achieving the cleans they want. He says: “Cleaning is usually about exploiting a chemical or physical difference between the coating and the substrate.”

Developing the company’s own range of products encouraged Jamie to go back to first principles and re-think what customers want and how they want to use the products.

On the vortex cleaner, which they call VorTech, he concentrated on keeping the size and weight to a minimum to make it easier for operators to use on-site, which often means on scaffolding, without compromising  quality. He has looked at the controls to make it easy to adjust as well as making the output measurable and, therefore, repeatable, which can help achieve the level of conservation clean often required.

He has evaluated maintenance requirements to make it cheaper and easier to replace wear parts and addressed issues of variable power supply, from the mains and generators.

But he not only wanted VorTech to be efficient and user friendly, he also wanted it to be affordable. The standard model with a 24-litre pot, high flow 25mm pneumatics, vibro and manual granulate valve, 110V air cooler, 20m hose set with manual adjustment and 9.5mm nozzle is £6,995 (plus VAT).

The vortex cleaner earned its reputation under the name of Jos. That name originally related only to the nozzle, which uses ceramic and tungsten carbide components to swirl the cleaning particles so they hit the surface at all angles, producing an effective clean without harsh abrasion. The original German distributor is no more, but Jos solid state nozzles are still produced and Restorative Techniques sell them as the Jos Piccolo (3mm) and Micro (5mm). But they also produce their own 5, 9.5 and 10mm VorTech nozzles, which can be dismantled so wear parts can be replaced without having to replace the whole unit – again reducing costs for the operator.

Add hose-mounted pressure and granulate adjustment to the standard model of the VorTech so the operator has instant control at the business end and the price is £8,400. In either case, delivery with induction on using the VorTech, including free operator update training, is all included in the price.

Restorative Techniques also went back to first principles for their ThermaTech superheated water cleaning system.

People call this a steam cleaner but it is not. It uses water heated to 150ºC rather than steam because water cleans stone better as a liquid than as a gas.

It is kept liquid at the higher temperature by being under pressure – you might remember from your physics lessons at school that water boils at higher temperatures as the air pressure increases. The pressure also aids the cleaning process and means less water is used than with a typical low pressure hot water washing system.

As well as rapidly cleaning off carbon and other atmospheric deposits and algae, superheated water is hot enough to soften many types of coatings  that the water will then simply wash away.

ThermaTech is protected by a tubular steel frame with welded-on lifting points for safety and pneumatic tyres for easy movement around site. It has a 110V / 240V dual voltage heater and a jerrycan fuel tank that makes refuelling easy. There are 24V boiler controls, twin safety valves, and dual thermostat controls with displays showing pressure and heat.

The red pipe from the boiler to the lance held by the operator – red as a warning that it is hot – is an indication of the attention to detail in the unit’s design. It has all been thought through to make use easy and safe and to simplify maintenance.

It is not always easy deciding whether to use VorTech, ThermaTech, poultices, latex, or a range of other formulas and chemicals all available from Restorative Techniques (although they do not supply strongly acidic or alkaline chemicals for facade cleaning). It depends on the type of soiling, staining or coating that needs to be removed and the substrate it needs to be removed from. For example, too much water on magnesium limestone can lead to salt migration, the results of which can be seen in the Minster in Doncaster.

“People want a formula for making the decision,” says Jamie, “so you can tick a series of boxes and come up with an answer. But it’s not that easy. There are many considerations, some site-specific.”