why build with SIPs?

Adaptability SIPs are adaptable and easy to build. Their inherent strength affords maximum flexibility in the positioning, configuration and size of door and window apertures. SIPs are primary, structural, load-bearing tconsultation with the Sipframe structural engineer.

Building control, insurance and financing

SIP construction shares the same category as other forms of lightweight construction with regard to insurance and financing. With the rapid increase in the use of SIPs, building control authorities are now becoming familiar with the systems. The fact that all Sipframe buildings carry a BBA certificate, a full structural engineer’s calculation report and detailed construction drawings together with full technical details helps to overcome any Building Control queries at an early stage In the process.

Thermal performance & air-tightness

The performance of a SIP wall is determined by the
thickness of the core material and its thermal properties.

In good SIP design, cold bridging is minimized at the SIP wall junctions and between upper and lower wall panels. . Sealant is applied between panels and wall plates to minimize air leakage to a level in the region of of permitted levels. For optimal performance, it is recommended that the design includes a Heat Recovery Ventilation system (HRV).

Structural ability Structural performance of SIPs in domestic and light commercial buildings is generally well above performance requirements. The composite nature of SIPs provides a light but very strong structure which does not rely on internal studding. Horizontal and vertical loading, SIP thickness and the material properties of the face OSB layers are most influential to the structural performance of SIP walls.

Horizontal & vertical load-bearing The SIP’s load-bearing ability relies not on internal studding, but on the strong bond between the various layers of the composite panel. A SIP’s components interact in a similar way to an I-Beam; the OSB faces act as flanges by taking compression and tension forces, while the rigid MPF core spaces them apart, providing the construction thickness and some shear stiffness. The thicker the SIP, the greater its load-bearing capability, but the panel’s weight does not increase correspondingly. While the bending stiffness of the core is generally discounted in design, its sheer resistance is of major importance to the stiffness of the entire SIP. This also affects the ‘creep’ performance of the SIP, which needs to be assessed, especially when SIPs are used in floors and roofs.

Racking performance

SIPs throughout the world have been subject to extreme wind load from hurricanes etc, and have survived without sustaining major structural damage. Studies have established that the bottom rail detail design is the main influencing factor in the SIP wall’s successful racking performance.

Acoustic performance

Acoustic performance is strongly dependent on the detailing, such as the jointing of the SIP construction system and its connection to floors and ceilings. Provided Sipframe guidelines are followed, SIPs can achieve an average sound reduction of 58dB for separating walls.

Fire performance

Maintenance of the structural bond between the various layers in a SIP is a crucial factor in its resistance to fire danger and to degradation of the exposed SIP face layers. Other components, such as jointing, also impact on the fire resilience of SIP construction. Plasterboard is generally installed on the SIP’s internal faces to ensure adequate fire resistance (30 to 60 mms), and therefore, reaction-to-fire performance, such as rate of flame spread, does not generally govern the design of SIPs.

Heating As Sipframe buildings are extremely energy efficient, the heating requirement is small compared with conventional forms of construction. For our ‘passive’ range, (180mm to 240mm SIP external walls) heating demand can, in the main, be met by ‘solar gain’ light bulbs, body heat from occupants, cooking, fridges, washing machines etc. For our ‘low energy’ range (125mm to 150mm SIP external walls), heating systems can be downsized by up to 50%. Needless to say - whatever level of Sipframe building is chosen, huge savings in running costs can be achieved.

Ventilation

A Heat Recovery and Ventilation system is highly recommended in Sipframe buildings, which are considerably more airtight than those produced by conventional forms of construction.

A healthy indoor climate requires an air change rate of at least 0.5 air changes per hour at normal air pressures. In Sipframe buildings, this can only be achieved by the introduction of mechanical ventilation.

Building regulations encourage builders to “build tight, ventilate right”. The introduction of ventilation with heat recovery is good practice in energy terms.

Design

Sipframe building systems offer architects complete design flexibility, with the capability for high-rise design up to 4 storeys, with SIP supported, concrete slab floors.

Sipframe provides full engineer drawings based on architect plans, together with structural calculations.

Our engineers are available to discuss projects with architects at the early design stages to enable maximum benefit to be achieved using SIPs.

SIPs can also be hung on steel-framed buildings to provide a fast, highly insulated outer wall ready for external finishes.