Assessing the Value Gains of Offsite Construction

Direct comparison between the material costs of Structural Insulated Panels (SIPs) and traditional building materials tells a small part of the story. While these costs are comparable, a full value analysis of the lifecycle – from design through to the eventual decommissioning of the building – reveals a compelling picture.

Offsite is generally a more design-centric process than traditional construction. The details of M&E fit out and service connection are fully resolved during the design phase, often using a BIM model. Building fit out is much simpler and easier to schedule. There are no last minute design changes and delays. Onsite drilling and reworking to accommodate ducts, pipes and cables, which could affect structural integrity, are also unnecessary.

Reliable Programme Scheduling

Some costs are hard to quantify, simply because they result from the unpredictability of traditional construction. The linear nature of traditional methods (one phase or trade can’t start until another has finished), means that each delay has knock-on effects.

Labour or material shortages, bad weather, glitches not identified in the plans – these all cause unpredictable delays and additional costs. If the building completion is delayed there will be additional costs in lost revenue and cash flow.

SIPs are fabricated in a controlled factory environment in parallel to ground and preparatory works. They are rapidly and reliably assembled on site so buildings are finished weeks earlier than with traditional methods. This reliability over timing, completion and cost is a significant value gain for many projects.

SIPs are also not affected by differential settlement, minimising post-handover defects.

Waste Reduction

Waste is significantly reduced using SIPs. The engineering process maximises the use of off cuts and all panel components are recycled. There are further waste reduction benefits throughout the lifecycle; from wooden pallets and shrink wrap used to deliver traditional materials to the absence of waste blocks, tiles or insulation materials that you see on a typical construction site.

The Waste and Resource Action Programme (WRAP) estimated in 2007 that SIPs offer a 50-60% waste reduction compared to traditional linear construction. In our experience these estimates are conservative.

The WRAP report also cites the ease of dismantling and recycling of panel components at end of life compared to building materials bonded with cement.

In Service

SIPs have inherently high levels of thermal insulation. They fit tightly to achieve airtightness. The internal environment of a building constructed from SIPs is easy to control with minimal heating or cooling. Arguably, the technology represents the most cost-effective way to meet demanding standards such as Passivhaus.

Energy and carbon savings throughout the building lifetime are significant. Achieving comparable insulation levels with traditional techniques would add complexity, cost and wall thickness to the structure.

The SIP story is one of lifetime value gains. Because Innovaré designs, manufactures and installs SIP systems, we are uniquely placed to help contractors realise these value gains at every stage. For more information on how to begin your SIP story get in contact on 0845 674 0020 or email enquiries@innovaresystems.co.uk.