Chemical / DOFF Cleaning System Stone Cleaning
Water and Detergent
This is perhaps one of our milder chemical treatments that we use on surfaces which only have a little dirt to remove. Typical areas where this treatment is used include stone facades or fragile stone types. A specially formulated detergent is applied using a spray onto the building or surface, using low pressure. The detergent is then rinsed from the surface using a high-pressure cold water jet but occasionally we may use hot water which further improves the effectiveness of the treatment. Detergent treatments are often used on artificial stone and we have the expertise to remove the correct amount of dirt leaving the masonry underneath as good as new!
The process of brick restoration commences when we start to apply a chemical, specifically formulated for stone masonry work to all exterior walls. Once this solution is combined with warm water and rinsed off the building it gently removes the grime and pollution leaving restoring the brick to its natural state. You may be concerned that the chemicals will damage the brickwork but you can rest assured that the technique we use and solutions we apply will certainly not damage any of your stone or brickwork.
Evalution for Chemical Cleaning of Stone
For buildings or stonework which have become heavily stained or dirty due to common pollutants, we will evaluate the stone before deciding on the most suitable acid treatment. It is really important that the right concentration of acid is used; too little and it will not clean effectively and too much may cause damage to the underlying stone. Before we begin any work we will thoroughly protect any surrounding stonework or surfaces with an acid and water resistant cover as a safeguard. Acid treatments are then applied using low-pressure spray tools before being left to work and then sprayed off with superheated steam. Due to the copious amounts of water used during these treatments, the residual acid is very weak and extremely safe.
Sodium Hydroxide Chemical Cleaning
There are also other forms of chemical cleaning available including the use of Sodium Hydroxide which can effectively remove carbon which has clung to the surface of the stone. Sometimes this is particularly useful when the stone has been damaged by smoke or certain types of paint. Using our expertise we have extensive experience working with all varieties of stone and brick and can remove all kinds of things from routine dirt and grime to paint and graffiti.
DOFF Super Heat Steam Treatment.
The final solution that we offer is using steam applied through a piece of equipment known as DOFF. It is applied at 150C and is ideal if you are looking to remove oil-based paints on soft surfaces including brick without incurring any damage to the brick or stone. It is also a great way to remove biological growth from buildings and walls.
Here at City Stone UK, we strive to provide the very best stone cleaning services in and around London, using our knowledge and experience combined with the latest technologies to effectively restore your building leaving it in pristine condition. If you are looking for any type of stone cleaning service, contact us today to arrange your quotation.