What is it and what does it mean for you?
This 3-Minute Read summarises the guidance from the ESFA ‘Concrete cladding – monitoring building condition’.
The guidance outlines:
- How to recognise if your school buildings have concrete cladding.
- What defects can occur in concrete cladding.
- How to implement inspections.
- What should be in a concrete cladding risk assessment.
Any school that becomes aware of severe cladding defects can have their cladding replaced through the Priority School Building Programme (PSBP).
What is concrete cladding?
Concrete cladding is a form of concrete that is prepared, cast and cured off-site to be used in building; an example of concrete cladding can be seen in the image below. Concrete cladding is used in many schools as a building resource – it can, unfortunately, suffer from defects that schools need to be aware of. The earlier a defect is found, the easier it tends to be repaired.
How to identify concrete cladding in school
Schools should conduct a preliminary check, inspecting the school building and identifying the signs of concrete cladding. This check should be made by the headteacher and the site manager.
The list below indicates what concrete cladding panels typically consist of:
- Concrete that is compact, of the required thickness and well finished.
- Brackets that are fixed securely and corrosion resistant – there are normally four brackets per panel; the brackets can be made of concrete, mild steel or stainless steel.
- A vapour barrier – found at the back of the insulation material, either metal foil or membrane material.
- Interfaces, such as acoustic barriers and fixings, that should be permanently secured.
- Securely attached and complete seals.
- Steel bars (‘rebar’) may also be used for reinforcement.
Identifying cladding defects
Once the preliminary check has been carried out, schools should carry out a standard inspection on their concrete cladding. This should be a visual check that includes the use of binoculars to inspect the areas of the building that are difficult to access.
It is not unusual for concrete cladding to suffer from defects and if these are left, the repair process can be costly for schools. It is, therefore, advisable for schools to carry out assessments regularly; the ESFA recommends a routine check on a 6-monthly cycle.
- During the inspection, schools should look out for six different criteria (as shown on the following slide), these are as follows:
- Significant cracks over 0.2 metres in length (these are the most common defect)
- Delamination – where layers of concrete are exposed
- Stains emanating from corroded steel
- Movement of a whole cladding unit/non-parallel gaps between units
- Significant changes in colour in parts or all of the panel
Carrying out a standard inspection
An inspection should be made by at least two members of staff, this is usually the headteacher and the site manager, every six months.
Use the images on the previous slide as a guide to carry out the inspection. If any of these defects are found then the time, location and names of those carrying out the inspection should be noted down.
Any large defects found should be addressed immediately, potentially through the PSBP. Minor defects should be considered and an action plan should be put in place so repairs are carried out soon after finding them.
Please note: any school planning an inspection or construction activity should consult a health and safety advisor.
Inspectors of the building should ensure their search is thorough by using cameras with a high resolution zoom to identify any defects on higher up concrete – this is recommended at intervals not exceeding 12 months.
Using cameras with a high resolution zoom can help display evidence of deterioration over time.
- Routine surveys should include actions to identify and record the following:
- Delamination of the material
- General condition of the concrete area: cleanliness, unevenness, etc.
- Presence of cracks and crack width and length
- Condition of joints and/or sealant
- Presence of water, either settling on the surface or running over it
- Prevailing temperature and weather conditions on day of inspection
When carrying out inspections, focus on areas such as:
- The periphery of windows and doors adjacent to or within the precast panels
- Ground-level interface with the facade, in particular any dampness
- Drainage areas including gutter and downpipes
- The corners of the building – this is an area where internal reinforcement does not always get sufficient concrete cover
- Services (e.g. water pipes) and ducting that penetrate the facade
- Any damp areas on the facade, or visible white marks
- Cracks: this is essential and is covered in detail within the ESFA guidance
- Cladding units out of alignment/moved
- Seals between units
When to seek specialist help
- If, after a standard inspection, significant defects have been identified and a more detailed inspection needs to be carried out, the school should call in a specialist.
- The specialist, for example a surveyor, will be able to inspect the building using more technical equipment to conduct a more thorough inspection.
- Engaging specialists may be essential to identify all of the causes of any defect.
- Read and understand ‘Concrete cladding – monitoring building condition’.
- Assess the current risks posed by your external premises using our External premises checklist.
- Complete a concrete cladding risk assessment.
- The risk assessment should be able to answer the question – is the defect likely to result in pieces of concrete or an entire panel falling?
- Carry out a standard inspection of the concrete cladding in school.
- Call out for a specialist inspection if required.
- Establish with the ESFA whether the concrete cladding is eligible to be replaced through the PSBP.