Client: Torfaen County Borough Council, Garnteg Primary School

Project: The client’s school building was in a very bad state with over 15 years of red and black algae growth, moss, lichen build up and staining which was very off putting to new potential children and parents wishing to come to the school. The school had an excellent record for teaching and a fantastic range of facilities, but the external façade was in need of attention. The local authority called APT after the head of the school requested help to find an algae removal solution or to enhance the visual impact of the school.

The Challenge

Several companies had already quoted for cleaning and re-painting the k render surface and some commercial cleaning companies did not respond after seeing the extent of the algae problem. There were several issues with the cleaning programme, the school was built over three levels and some with very limited access, and the school would remain open whilst the cleaning took place which included very young children, teachers and parents to be considered. This was all taken in to account during the consultation with the client and allowances were scheduled into the working plan for approval with the client and managed vigorously on a day to day basis with flexibility and allowances for any programme changes.

APT’s Solution

APT carried out a full survey of the property and there was over 3000 square metres of k render surface coating on three levels and some with very limited access. We discussed the type of cleaning and method with the client along with the ongoing future maintenance programme.

After receiving approval we arranged the cleaning program and hired the specialised lift access and allocated the materials including the APT k render cleaner and algae remover which would kill algae and remove moss and other surface stains (Algae Free). We carried out a test sample for approval by the property services manager and head of school. We completed the k render cleaning and treatment works over a 10 day period working late evenings and weekends to minimise disruption to the school programme.


The results spoke for themselves and the head of school and all staff and many parents commenting that the school was as good as new. The k render did not need to be painted as first proposed saving thousands of pounds.

– See more at: Case Study: K Render Cleaning at Garnteg Primary School – APT ICC