Ian Clay of SIPS@Clays offers a few points to consider when choosing the build method for your new home and why SIPs deliver the perfect solution compared with traditional brick and block construction
With so many decisions to be made when building your home, the build method and construction material you choose ultimately shapes the outcome both for the short and long-term.
As well as looking at the obvious elements of aesthetics, construction costs and energy efficiency, equal consideration should be given to design flexibility, speed of build and space efficiency. So, when you’re choosing a construction method to deliver all of the above, then you should look no further than structural insulated panels (SIPs).
Energy efficiency
If you’re building an energy efficient, sustainable home requiring low U-values and superior airtight qualities or building to Passivhaus standards, then the inherent qualities of SIPs must be considered.
Each panel consists of two sheets of oriented strand board (OSB), sandwiched around a rigid insulation core. The panels provide ‘built-in’ insulation to create a home that will provide low energy running costs for the lifetime of the property.
When compared to brick and block construction, which requires insulation to be fitted between cavities during the build process and needs more complex and costly solutions to achieve similar U- values to that of a SIPs build, the benefits of SIPs far outweigh traditional construction.
Just like brick and block, extra insulation can be added to a SIPs build to improve thermal performance but to much greater effect. For example, the Kingspan TEK Building System which is supplied in 142 mm and 172 mm panels gives superior U-values of 0.19 W/m2.K and 0.16 W/m2.K respectively. When additional internal insulation is added to either, the improved U-values far exceed what can be achieved with traditional construction for similar wall thicknesses.
While it is possible to increase the overall thermal performance of brick and block, by adding extra insulation, the negative effects of thermal bridging and resultant heat loss in traditional builds cannot be ignored.
The thermal conductivity of timber products is far lower than brick or block and SIPs in particular significantly reduce the effects of thermal bridging by creating an energy efficient airtight envelope. This results in superior airtight values, reduced heat loss and outstanding energy efficiency with minimal heating requirements.
Speed of build
Time is money and the build programme of your project is critical. Traditional construction is subject to a variety of external factors such as availability of trades and materials, knock on delays and of course, bad weather. Projects can become seriously delayed by prolonged spells of rain, snow and freezing temperatures with interruptions to the programme, creating a ripple effect that wastes time and eats into your budget.
Building with SIPs is not subject to fine weather, the availability of skilled wet trades or any other onsite delay. In fact, as the panels are precision engineered offsite and delivered to site ready for immediate erection (which typically takes between two and three weeks, depending on size and complexity of the build) an accurate programme can be created, ensuring both timescale and budget is adhered to.
Design capabilities
There is a common misconception that SIPs structures have to be boxy and boring; in fact it’s quite the opposite. The flexibility in design and ease of construction means there are no limitations to what can be achieved and design complexity is no barrier to building your new home with SIPs.
One of the many design benefits of using SIPs, and in particular the Kingspan TEK Building System, is that the system will always provide a larger floor area comparatively, than can be achieved when using traditional build methods due to the thinner construction components.
This is particularly evident within the roof space where unlike brick and block builds that require roof trusses, SIPs homes rarely require trussing. This obvious benefit maximises living space by providing an additional room in the roof which subsequently adds value to the completed build.
The flexibility and simplicity of SIPs allows for practical amends to architects drawings prior to fabrication and a credible SIPs designer can ‘design in or out’ elements of the plans to enhance your project.
Our in-house design team, for example, uses a 3D CAD system to create geometrically complex structures and we provide interactive imagery that allows customers to see exactly what their new home will look like from every angle.
When compared to traditional construction where design amends can be costly, time consuming and will inevitably delay the build process if inaccuracies or design errors are identified, the superiority of SIPs really shines through.
Small, challenging plots
For every housebuilding project, the plot will dictate what can be built. It defines size, shape and layout of a dwelling, its orientation, and it can even influence the most suitable method of construction to be used.
Traditional methods of construction may immediately exclude many smaller and difficult to access plots deeming them unsuitable for building, and if you think you’ve found your ideal site this can be disappointing news to bear.
Every millimetre of space counts on a small site so construction, storage and waste areas need to be utilised effectively to allow maximum dwelling space and efficiency onsite. The offsite engineering of SIPs means the superstructure of the building is prefabricated in a factory environment then delivered to site ready for immediate erection.
This not only speeds up the build process but reduces the amount of onsite labour and materials required, it minimises waste and importantly means there are far fewer site deliveries when compared to traditional builds. This is especially beneficial if access to your plot is restricted or you’re building in a conservation area, for instance.
Cost
There are many factors to consider when comparing traditional construction with SIPs and while on the face of it traditional materials may appear to be more cost effective than the market leading structural insulated panels; overall project costs cannot be accurately compared like for like.
Shorter build programme, fewer labour requirements and reduced equipment costs of a SIPs project will significantly influence the bottom line. It is also important to compare the life time costs and the energy saving benefits of building your new home with SIPs. There are many factors that affect a direct cost comparison and a holistic and pragmatic approach should be taken.
SIPs provide so many benefits – flexibility of design, speed of build, energy efficiency and versatility, all of which are critical factors for today’s self- builders and when compared to traditional methods of construction, offer an ideal solution to building your perfect home.
Ian Clay is a partner at SIPS@Clays