Hitesh Pattni, Northern Specification Manager at SFS, discusses how working with a product manufacturer in construction to select an appropriate system solution, provides more reassurance that building envelope performance will be maintained for the length of the given warranty. Attempts to specify system solutions, however, are often undermined by proposed substitutions for individual components.
In 2018, Dame Judith Hackitt recommended that a better understanding of product performance within system build-ups was needed. From the perspective of producing robust specifications that are fit for future, therefore, one of the best ways to meet recommendation is to get a manufacturer engaged on a project in the early stages.
Do individual product warranties guarantee system performance?
Product warranties are designed to provide some reassurance that a certain level of performance will be delivered for a particular period of time. But if you select a series of components that all offer, say, a 25-year warranty, does it automatically follow the components will work together as you need them to?
Individually-selected components are unlikely to have been tested together, so there’s nothing to say what performance they should or will provide in any given build-up. The performance of each separate component is likely to be caveated due to uncertainty about the performance and installation of other components they directly interact with.
Ultimately, all of this results in a lot of work for specifiers and clients at any given stage of a project especially when trying to get written confirmations from different manufacturers regarding product compatibility. That is only made worse when specifiers find themselves in negotiation with contractors about alternative solutions.
Short-term vs long-term thinking
It’s not hard to understand why contractors propose product substitutions that lower costs while seemingly offering similar performance to the original specification. If a client’s primary goal is to complete a project for as little money as possible, then such a substitution will be even more attractive.
As part of being fit for the future, a robust specification should also deliver value over its whole life, and not purely upfront cost. You would expect clients, backed by their design and specification team, to prioritise lower long-term costs, but we all know that’s rarely the case.
Whatever the rights and wrongs of it, saving money in the short-term often takes precedence. A reluctance to commit to one specific manufacturer or solution can be understandable, especially if there’s legitimate concern that product substitutions will later ‘undo’ design and specification work. But nobody understands a component or product better than its manufacturer.
By discussing project specifics with a manufacturer, the team can advise on what to look for, and what to avoid, in order to achieve the client’s end goal. They can advise on suitable components that will deliver building envelope performance and play an important part – whether thermal performance, fire safety, sustainability or corrosion. For example, they may generally recommend that fixings and framing components have the same warranty as the preferred façade panels. Or they may recommend a specific manufacturer’s components that they know will work as part of the complete build-up.
Does manufacturer engagement risk limiting choice?
Aiming for system specifications as part of the design and specification process does not mean limiting choice. The manufacturer or supplier of building envelope systems are very unlikely to produce every component themselves so they must have a pool of suitable components available from partner manufacturers and suppliers.
Specifiers can therefore select from the compatible components, supported by the system supplier to meet the project’s needs. All the while, they can be confident that the overall performance is backed by testing and certification. The system and its components should reflect the life expectancy and maintenance expectations of the client – and it’s approach should be the standard way to ensure that is the case.
What does robust and long lasting mean?
A robust building specification is one that meets the needs of the users today and in the future and will stand up to value engineering scrutiny.
What are envelope improvements?
Improvements can include upgraded openings e.g. windows & doors, additional insulation added to the external wall through rainscreen cladding or elements to manage solar gain.
What are the factors that affect a buildings envelope?
A building’s shape, solar orientation, interior layout and size are some factors that affect its energy use and the requirements of the building envelope.
What are the major materials/components that comprise the building envelope?
The main components are; exterior walls, foundations, roof, windows and doors. The performance of a building envelope is impacted by a number of sub-systems, such as: heating, cooling and ventilating, mechanical, plumbing and electrical systems.
For further information, call 0330 0555888 or visit uk.sfs.com