PIR or EPS sandwich panels for a replacement roof: how do the options compare?

Ask for the core thickness, outer profile and thickness of both metal facings in the quotation. Check the cover width and the shape of the joint. Similar colours do not establish that panels will fit together. For a partial roof replacement, include compatibility with the retained panels in the specification.

The table compares two example ranges of steel-faced roof panels. The PIR core has a declared thermal conductivity of 0.022 W/(m·K). The EPS version has an expanded polystyrene core with a density of 12.5 kg/m³. The U-values apply to these particular panels. Use the data for the specific products in your quotation when comparing alternatives.

Under the same conditions, a lower U-value means less heat passes through the panel. To choose a thickness, establish the roof requirement and the intended indoor temperature. Assess the panel value together with the junctions and other details of the roof assembly.

Capacity depends on the facings, profile, thickness, span and number of spans as well as the core. The existing frame may restrict the choice. For each option, check snow and wind loads, loads from rooftop equipment and the fixing arrangement.

Use the load table for the exact panel and core. A PIR load table cannot be used for an EPS panel of equal thickness. Check bearing widths and permissible deflection. If one option needs extra purlins, include them in its cost. Inspect the existing structure and its connections as part of the comparison.

PIR and EPS are organic core materials. Consult the classification documents for the finished product and roof. Reaction to fire, fire resistance and external fire performance describe different properties. Check each property required for the project against the corresponding classification.

The scope of a classification may depend on thickness, supports, loading and details. Check that the proposed renovation falls within those conditions. The name of the core alone cannot establish a fire class. Additional project requirements may call for a different panel variant or a different roof assembly.

In humid rooms or spaces that are washed frequently, the internal facing and its junctions must withstand the exposure. Select a coating suited to the chemicals, temperature and maintenance regime. Apply the same checks to fasteners, flashings and seals. An enclosed core does not protect the exposed surfaces.

For the outer facing, check roof pitch, slope length and the arrangement of end laps. Requirements can vary by system. Where part of the covering remains, specify the transition between old and new panels. If the profiles differ, adding sealant alone will not produce a suitable joint.

Price the panel thickness that meets the common specification for each option. Include framing, installation, transport, flashings and the cost of any interruption to operations. Equal-thickness samples illustrate material differences, while the thicknesses required for a particular building may differ.

Estimate potential heating savings from the energy balance of the whole building. A percentage reduction in the roof U-value does not translate directly into the same reduction in heating costs. Include ventilation, vehicle doors, walls and operating temperature. An environmental comparison also needs comparable data for solutions delivering equivalent performance.