DOFF and TORC are two proprietary Stonehealth systems used to clean masonry and stone facades after construction or refurbishment work: DOFF uses superheated, low-pressure steam (heat-based) to remove paint, algae and biological growth, while TORC uses a low-pressure swirl of air, water and fine granulate (particle-based) to remove ingrained carbon, limescale and graffiti. They are often used together for full facade restoration.
What is the DOFF system?
DOFF is a superheated-water steam cleaning system manufactured by UK company Stonehealth. It heats water to around 150C at the nozzle but applies it at low pressure and low volume -- around 3-5 litres per minute -- so it lifts paint, moss, algae and other biological growth from masonry, brick and stone without the abrasive force of pressure washing. Because it is heat rather than pressure based, it is commonly specified for historic, listed or otherwise sensitive facades where standard jet washing would risk damage.
What is the TORC system?
TORC is Stonehealth's particle-based system: a low-pressure vortex of air, water and a fine granulate abrasive. It suits removing ingrained carbon staining, limescale, cementitious residue and graffiti that a heat-based system like DOFF cannot lift, because it works by gentle mechanical abrasion rather than heat.
When are they used after construction work?
On a construction or refurbishment project, DOFF and TORC are typically used at the facade-cleaning stage -- removing render or mortar splashes, biological growth that has developed during a long build, or staining picked up while the building was under wraps. They are often used together: DOFF first to remove paint and biological matter, then TORC for any remaining carbon or mineral staining. See our external facade cleaning service.
Who should carry out DOFF/TORC cleaning?
Both systems require trained operatives -- Stonehealth runs its own accredited training and approved-contractor scheme -- because incorrect use (wrong temperature, dwell time or granulate) can still damage sensitive stone. Always check a contractor's training and experience with the specific system before instructing facade cleaning on a listed or historic building, and confirm access -- see high-level cleaning.