Why choose Structural Insulated Panels (SIPs)

Why Choose SIPs?

As demand for energy efficient buildings increases, so too does the popularity of Structural Insulated Panels (SIPs).

SIPs are composite engineered products in a sandwich formation, where the ‘bread’ is typically sheets of orientated strand board (OSB), and the filling is a low-density, cellular foam insulating core. Bonded tightly together in controlled factory conditions forming a stressed-skin panel construction, the composite structure of these panels produces high-performance yet lightweight components with good loadbearing capabilities, suitable for use as walls and roofs for residential and commercial buildings.

SIPs make a neat solution for a wide range of construction projects. We include an introduction as part of our timber industry training, along with other types of timber construction. Here are some of the top reasons for considering this sustainable sandwich option:


In the UK, the majority of oriented strand board (OSB) used in SIPS is made from certified and sustainably sourced softwood. And, many UK-based manufacturers of OSB use home-grown timber in their products, reducing transport related carbon emissions.

Waste is kept to a minimum with SIPs, because any larger off-cuts of timber and board material can be used in the production of other panels or ancillary components, while smaller off-cuts can be used as biomass fuel.

Efficient Insulation

SIPs make for an incredibly energy efficient building, offering good thermal insulation, because the insulation is built in as part of the structure.

SIP wall panels can be of any thickness, although most manufacturers will make panels between 100mm and 250mm thick. Most new build developments will have external wall U-value targets of between 0.1 W/m2K and 0.2 W/m2K, which SIPs can easily achieve.

Tightly built – by design

SIP buildings are capable of providing very good levels of airtightness due to the panelised construction system.

They would normally incorporate a vapour control layer (VCL) onto the warm (inner) side of the external walls. This primarily controls the movement of moisture vapour through the wall, but is also an effective air barrier. The vapour control layer/air barrier can be lapped and sealed at wall junctions, at the junctions with other external elements, such as windows and doors, as well as around service penetrations of the building envelope.

Counting the Carbon Benefits

The environmental benefits of building with timber are well known: the material has captured carbon dioxide from the atmosphere during growth; and this is then locked in to the building throughout its life and beyond, if materials are carefully reused.

But it is the design philosophy that underpins the use of SIPs – off-site manufacture, well-insulated and airtight fabric – that can particularly contribute to enhanced sustainability benefits in terms of reducing carbon dioxide emissions.

SIP structures are typically low in weight and so additional savings in embodied energy can be made in the design of foundations and supporting structures through the use of less concrete.

These energy efficiency measures ensure that, over the whole life of the building, the energy used in the manufacture of the SIP is likely to be more than offset by the reduction of energy used for heating (and cooling) the building.

As a timber frame consultancy, we offer independent checks on timber buildings for architects, their clients, main contractors and building owners. In addition, we can provide technical assistance on thermal performance, thermal bridging and low energy building design.

SIPs and their benefits are covered in more details in our timber frame for engineers training course, which looks at the fundamentals of timber frame construction from an engineering perspective.

To speak to one of our engaged experts, call us on +44 (0) 1494 569 601 or email us.

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