Superheated Steam (DOFF) Cleaning
Surface Preparation – Nationwide
Low Pressure Superheated Steam Cleaning
A data sheet on our Superheated Steam cleaning services, a suitable summary for printing is available in PDF format, Superheated Steam Leaflet; Stonehealth market their machine as DOFF(TM), and conservation officers often specify DOFF cleaning as a result. We don’t actually use DOFF machines (we can do if you insist) but a competitor product called a Thermatec, but both machines generate superheated, low pressure steam at around 150 degrees centigrade, that is effective at cleaning stone and brick work, and providing a weed killing / mould killing and indeed sterilising surface treatment. In recent months we have used this machine in Lancashire (Bolton), Lincolnshire (Lincoln) and in central Nottingham.
Although we specialise in using a listed building approved variable pressure sand jetting system which causes minimal damage to an underlying surface and is flexible enough to tackle most property restoration cleaning tasks.
That being so, there are times when using an abrasive system may be more than a substrate can cope with, and low pressure superheated steam may be the answer. It is generally slower, and less messy, and can be quite effective for surface contaminants such as algae and grime. Subsequent cleaning with the sand jet can remove stubborn stain. In the photo below we are cleaning the algae of aeons from the Humber Bridge offices – so that a spray painting contractor could re-spray the panels.
Stone Cleaning
In Aberdeen we removed Litchen and moss (and grime) from the old Customs house almost in the centre of the city as it was converted from an office block to residential use. The main contractor recognised that to use our sand jet (which we had many times for him) in such a central part of the city was going to cause problems – so the bulk of the building was cleaned with steam – and then a day of sand jet ‘fun’ was had cleaning up some of the stubborn stains.
Some more examples of Stone Cleaning
The Old TSB bank in the centre of Hull – stonework cleaned in the summer of 2024.
High Level Cleaning
The Old TSB bank in the centre of Hull – stonework cleaned in the summer of 2024.
War Memorial Cleaning
Fences and gates are very inefficient to clean with the sand jet – but clean up well and rapidly with High Pressure Water.
Dirty Brick Cleaning
This was the effect of steam cleaning brickwork on a building in the centre of Harrogate – as you can see – the Thermatec machine is very effective at removing grime and algae – but less so the long term discolouration of the bricks . Our sand jet machine would clean the algae etc, and be effective at brightening those dark bricks as well.
Key Benefits
- Very Gentle compared to other techniques, but diesel steam generator does cost a bit!
- Our machines allow variable temperature and pressures – to allow flexibility.
- Keeping to the requirements of BS 8221-1&2 :2000 the British Standard Code of Practice for Cleaning and Surface repair of buildings.