Modern Methods of Construction: BOPAS and Build Warranties

Interest in custom build and modular housing is growing rapidly, but housing associations and developers considering this way of building must not overlook accreditations and warranties – specifically the Buildoffsite Property Assurance Scheme (BOPAS).

What Is BOPAS?

BOPAS has been jointly developed by Buildoffsite, The Royal Institution of Chartered Surveyors (RICS), Lloyd’s Register and BLP Insurance, in consultation with the Council of Mortgage Lenders (CML) and the Building Societies Association (BSA). The scheme has been designed to instil confidence in alternative construction methods throughout the construction and housing sector and aims to assure the lending community that innovatively constructed properties, against which they may be lending, will have the longevity to be saleable for a minimum of 60 years.

How Does It Work?

BOPAS is an accreditation of Modern Methods of Construction (MMC’s). Lloyd’s Register and BLP carry out a durability and maintenance assessment of the building system’s design and manufacture, by examining for example, off-site modular home factories, materials used and construction standards. The accreditation assesses and facilitates the implementation of best practice throughout the project development, through concept, design, manufacture and construction.

Developers linked to BOPAS approved manufacturers, with lending approvals-in-principle, can go ahead with developments and offer properties for sale, safe in the knowledge that the construction method meets lender mortgage standards.

Purchasers make applications to lenders and lenders instruct valuers in the normal way to carry out mortgage valuations when applications are received. Valuers will recognise the unconventional forms of construction when on site and at this point, applications on innovative construction types usually fail.

A One Stop Shop

The BOPAS scheme is a standalone accreditation and is not, in any way, a quasi-warranty whereby defects are rectified by the contractor or accreditor for a period of time post construction.

The BOPAS accreditation is, however, directly affiliated with the BLP’s specialist new home warranty and every BOPAS approved building system will be confirmed as acceptable by BLP for the provision of housing warranty insurance (BLP Secure). BLP Secure is a 10 or 12-year warranty insurance policy for residential developments which meets the cost of re-instating the premises if a structural defect occurs.

The Others…Build Warranties  

MMC’s do not have to obtain third party accreditation, such as BOPAS in order to gain Build Warranty Cover. More familiar warranty providers, such as The National Housebuilding Council (NHBC), the UK’s largest new home warranty provider, Local Authority Build Control (LABC) and Premier Guarantee offer similar accreditation schemes to ensure MMC systems satisfy their technical standards.

If a construction method does not meet the Warranty provider’s technical standards they will, regardless of any third party accreditation, want to verify or, in some cases, supplement the third party accreditation themselves before issuing any form of warranty cover. Third party accreditations, such as BOPAS are, in fact, competitors to their own internal accreditation schemes.

Modern methods of construction, products or systems that have third party approval will still need to be structurally approved on a site by site basis depending on the layout and loading of the component.  Thermal properties and measures to prevent condensation will also require specific assessment depending on the property’s exposure and orientation.

What we must not forget is that BOPAS is specifically targeted at lenders to ensure purchasers can obtain a mortgage on unconventionally constructed properties. There is no doubt a third party accreditation would give warranty providers more confidence in the construction method, but unless the alternative method is a simple system that explicitly meets the technical standards (e.g., steel frame modules) warranty providers would want to scrutinise and verify the systems internally before issuing any form of warranty.

The End or the Beginning?

Such pioneering methods of construction are futile without the protections and warranties that are provided so nonchalantly to conventionally constructed buildings. BOPAS is taking steps to bridge the current void between the protections afforded to conventionally and alternatively constructed properties – a priority if MMC’s are to flourish in the future.

Also, the news that Swan Housing Association has recently become the first housing association to complete the accreditation process for their precision engineered modular CLT homes typifies the scheme’s success. BOPAS is on course to achieve what it set out to do: to provide faith and confidence in MMC’s for asset valuers, mortgagors and surveyors, warranty providers, developers and housing associations.

BOPAS has somewhat stemmed the scepticism directed at MMC’s, and adds weight to the argument that MMC’s could revolutionise the construction and property industries.

For further information, please contact Thomas Evans.


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