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SIPs and SAP calculations

SIPs support a fabric-first approach to building structures by focusing on reducing a home’s heat loss, you can achieve a low-carbon, sustainable house that’s affordable to heat. It’s really about maximising the insulation and airtightness, managing solar gain through screening/shading and solar reflective glass, careful design of cross ventilation, and minimising thermal bridging with our pre-modeled details.

Part L – New Building Regulations: Structural Insulated Panels come into their own when it comes to complying with the increasingly stringent Part L of the Building Regulations and in particular the SAP 2010. The SAP rating is a measure of the overall energy efficiency of a dwelling and takes into account a number of factors including the efficiency of the heating system, the u-values of all of the building elements, and any renewable technologies that might be being used. Several of these areas are enhanced by using Ecologic SIPs. Here are a few of the benefits that highlight why a SIPs build system is perfect to help you with your SAPs test and overall EPC rating.

Excellent U-Values

Through extensive research and development, we have created a range of products that allow us to achieve u-value that both meet and exceed the new targets for walls and roofs. Our product specification accomplishes low u-values for your walls (0.18 or 0.14) and pitched roofs (0.11) helping you to heat your property more efficiently and exceed the new Part L target u-values.

You can find out more technical information about our Eco Premium and Eco +Plus® product ranges here.

Excellent U-values. SIPs eco friendly building

Improved Air-Tightness

Due to the inherently air-tight way that SIP frames are constructed, structural insulated panel builds typically have lower air pressure results, meaning easier SAPs. A typical Ecologic SIPs house will achieve between 2 and 4 acph @ 50pa – see this review from a recent client on Trustpilot

‘Our EPC came in at a very nice 97 A rating which is the best we have ever achieved and the air test guys said this is the best building they have tested.’ Chris Scorer, Developer, Crowding Bricks

Improve Air-Tightness. Eco Friendly

Reduced Cold Bridging

Whereas with timber frame there is a repeating cold bridge in the timber studs at 600mm centers, due to the unique stressed-skin action of a structural insulated panel, SIPs do not have this issue. We supply and install around 30 – 40% SIPs splines rather than C4 timber in our builds, resulting in minimal cold bridging in the walls, making for better SAP results and easier compliance with Part L.

Reduced Cold Bridging. Thermal Efficiency. Eco Friendly

Lower Thermal Mass

Contrary to popular belief, SAP 2010 generally looks at lower thermal mass more favorably than higher thermal mass. Thermal mass is the ability of a substance to absorb and store heat. The higher the thermal mass, the slower it responds to changes in atmospheric temperature. SAP 2010 takes the view that if something responds quicker to heat changes, the user can turn off the heating/cooling quicker and therefore use less energy. SIPs structures have lower thermal mass than most other forms of construction.

Lower Thermal Mass.  Eco friendly

What do energy assessor experts say about the use of SIPs and SAPs?

These points are re-iterated by Sean Mills of Build Energy who is a leading provider of environmental and sustainability services to the construction sector.

“It’s more important than ever that new buildings reduce their energy demand. The best way to ensure that your project passes the new building regulations is with a fabric-first approach.

When fitted correctly, SIPs panels can offer significant benefits in air tightness and in mitigating thermal bridging and other gaps.

In addition, SIPs can provide a fast and efficient method to achieve the high levels of insulation necessary to meet current building regulations, often at more reasonable wall thicknesses than other building methods.”

Build Energy Logo

Additionally, take a look at the remarks made by Shaun De La Rue, proprietor of Thermal Acoustic Solutions Ltd, another prominent local energy assessment enterprise.

“ there are several benefits of using SIPs panels, including increased energy efficiency, improved air quality, reduced environmental impact, and lower utility bills. SIPs panels are known for their thermal performance, which helps to keep indoor temperatures stable and comfortable. Additionally, SIPs panels are a sustainable building material, as they require less energy to produce and generate less waste during installation. Overall, using SIPs panels can result in a more comfortable, efficient, and environmentally friendly home or building.”

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How can I share your panel PSI calculations with my energy assessor?

PSI Calculations

We have had our key SIPs junctions calculated and verified externally by a leading local energy assessment company, these can be really useful to share with your architect as part of determining your project’s overall SAPs calculations.  A document is available upon request.

For more downloads and technical information please visit our resources webpage.

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