Practical guidance on simple conservation issues.
The information on these pages is for guidance only we do not accept responsibility as a result of any person carrying out any works according to the advice contained in this web site. Always follow Health and Safety measures described on products, tools and materials. Jackfield Conservation Studio and TACS are not responsible for the work which you do, the responsibility is yours and yours alone!
Cleaning Glazed surfaces
Where glazed surfaces are concernedit is very important that the glaze should not be scratched during the cleaning process, make sure that the glaze is robust enough to withstand nylon ‘Scotchbrite’ pads, most tile glazes are but do a test area first. If there is any slight scratching of the surface use a soft cloth instead.
Any cleaning treatment on old ceramic tile is always experimental and is not bound to work, always find an unobtrusive corner in which to test your method or product.
If tiles are in large open public buildings, and there is no other vulnerable building fabric in the vicinity, and all health and safety considerations have been taken into account, steam cleaning is sometimes used as a first stage clean to remove the very worst surface dross, especially if the tiles are in particularly bad condition.
The best method for thorough and detailed cleaning is by hand.
Recommended cleaning products are ‘Syperonic A’ and ‘Vulpex’ spirit soap’, available from conservation suppliers, or ‘HG Extra’, ‘HG grease remover’, or ‘BAL Ceramic Floor Tile Cleaner’ available from good tile suppliers.
All products are non ionic, ‘Syperonic A’ is a mild detergent with a balanced ph, ‘Vulpex’ is an alkaline soap, whilst ‘HG Extra’ is a stronger detergent which contains phosphoric acid. HG grease remover is an alkaline cleaner and BAL floor tile cleaner contains sulphamic acid.
Whichever product is chosen, the tile should be pre wetted, the product should be applied neat onto the surface of the tile (with the exception of Vulpex which should be diluted according to the manufacturers instructions) and agitated manually, left for twenty minutes and then thoroughly rinsed off. The product should not be allowed to dry on the surface of the tile. Each tile should be given individual attention.
To agitate the detergent use ‘Scotchbrite’ green pan scourers. These are made of a plastic material which is abrasive enough to work the liquid into the body of the tile, but will not scratch the surface. Never use wire wool or any hard abrasive material.
Hardened substances which are on the surface of the tile, such as paint splashes may be removed using a ‘Stanley’ blade at a 45 degree angle, red plastic holders which hold the blade thus can be bought from hardware stores.
It is very important that the glaze should not be scratched during the cleaning process, make sure that the glaze is robust enough to withstand nylon ‘Scotchbrite’ pads, most tile glazes are but do a test area first. If there is any slight scratching of the surface use a soft cloth instead.
If black sulphides are prevalent on the surface of the glaze they can only be removed by hand. Use of power driven abrasives is likely to result in permanent damage to the glaze.
Wearing rubber gloves and eye protection are recommended against the effects of detergent splashes.
Copyright: Lesley Durbin Jackfield Conservation Studio Nov 2014
