Cladding due diligence

George Bouwens sets out seven key considerations.

Following recent high-profile incidents, the materials and specification used to clad buildings remains under the spotlight and has implications for contractors, landlords and tenants.

As building construction technology and building regulations have evolved the design and use of certain materials has been superseded. Change and improvements are nothing new in the built environment, but neither is preservation or refurbishment of existing and older properties. Our building consultancy team works on a daily basis with all types of buildings which use cladding systems. Here we outline some of our key considerations:

Knowledge of materials and products

Cladding is used for many reasons and often performs various roles as part of a building’s fabric, sometimes for aesthetics and sometime insulation, for example. It is used across all sectors in offices, industrial buildings, hotels and residential dwellings. Older cladding is not automatically noncompliant or obsolete. Buildings clad with composite or rain screen panels containing core material which may be flammable in isolation can still be regarded as perfectly fit for use. Identification of the cladding and its composition is the first stage of any survey. The use of the building In relation to wider fire safety, a clear understanding and assessment of the building use is important. For example, a single-storey property with sufficient escape routes and low risk use has a reduced level of risk than a multi-storey building where the risk is greatly increased and additional safety systems such as sprinklers may need to be installed.

Application

The design and application of cladding has to be understood just as much as the product specification. This is perhaps the most recent focus following a disastrous realisation of the ‘chimney effect’ which can arise in some instances when a building is retrospectively ‘over-clad’. Application, including fixing specifications and fire barriers, can be identified on site via a survey or through a review of construction documentation.

Condition

The insulation core of a composite panel or the general core of a rain screen panel is protected by the composite components and this reduces the opportunities for ignition. All cladding should be well maintained. The complete wall build-up and specification, position of cavity barrier, fixings and standard of construction are also all important factors. Beyond general wear over time, where we find cladding to be in poor condition this has normally arisen through improper installation or retrospective repairs where third party materials may have been used.

Installation of other fire mitigation systems

Although not all buildings require them, if the building is fitted with a sprinkler system throughout, is it operational, are the fire alarm systems tested and fully operation and the correct technical specification for the building, and are all the fire exit routes clearly marked and compliant?

Insurance

A clear understanding of the cladding product used will often be required for insurance purposes. A requirement for this is now more regularly coming to light during any purchase, sale or leasing transactions.

Further investigations

Identification is key to all of the above. In some instances a product cannot be fully identified. In this case we recommend parties should be prepared to instruct additional investigations which will normally involve a review of original construction documentation (where available), liaising with cladding manufacturers to establish the supplied product’s specification (most provide such information free of charge) or even undertaking a specialist intrusive survey.

By following these basic principles, with a good flow of information and parties working together we often find that a clear level of information can be obtained to satisfy all stakeholders involved in a transaction.