Further Information
For use on cream/brown sandstone and if diluted 50-50 or more may be used on bricks, terracotta and unglazed baked tiles. Ingredients prevent iron stain migration. Non viscous, coverage 3-4m²/l. This product complies with BS 8221- 1: 2000 recommendations for sandstone.
NORMAL CLEANING TECHNIQUES FOR MASONRY The basic technique established over many years has five stages carried out in order:- 1. To pre-wet 2. To degrease and prepare the surface for the acid cleaner. 3. To power jet off the surface debris. 4. To clean using the appropriate acid based product. 5. To power jet off the surface debris. The purpose of pre-wetting is to fill the pores in the masonry and mortar with water so as to prevent deep chemical absorption and retain the product on the surface where its cleaning action is needed and from where it can be removed more efficiently later. A cold water jet is normally used and each square metre of surface washed and wetted for about 30 seconds after which a short time is allowed (5-10 minutes) for surface water to drain down. This jetting also removes dust and loose organic matter from the masonry face. This should be carried out on all types of masonry except prior to using organic solvent based paint stripper or silicone water repellent or solvent based degreasers.
