What costs make up a sandwich panel roof?

Also record the type of facings and coatings. The internal surface may perform in a demanding environment even when the external surface looks similar to a standard one. The quote should relate to a specific variant. A general item ‘100 mm panel’ is too imprecise.

In the example we assume a roof slope 8 m wide and 6 m long measured along the slope. It has 48 m². A panel with a cover width of 1 m allows eight runs of 6 m to be planned if the details confirm such a layout. The dimension does not describe the permissible purlin spacing.

With a wider module the number of pieces and the final cut will differ. Openings and penetrations may increase waste. Do not deduct their area without drawing out the panels. The ordered material must retain the necessary edges, bearing and continuity of connections.

Let us assume a notional net price of €40.50 per m² of panel. For 48 m² this gives €1,944.00 net. This is an assumption for the calculation, not a current offer. A change in the rate of €4.63 per m² changes the panel total by €222.24. This allows the significance of the difference between variants to be assessed.

For comparison, the same range of parameters must be retained. A different core, coating or facing thickness may justify a different price. A lower U does not automatically mean the same load-bearing capacity. Each proposal should meet the full set of requirements.

In the calculation we take €416.61 net for the processing and €138.87 net for the fixings and seals. These amounts are examples. The actual list is produced from the length of the canopy, the sides and the top end. Additional transitions must be calculated separately.

On a small roof, the edges account for a large share relative to the surface area. That is why the cost of accessories cannot always be described by a single rate per m². Do not save by omitting details. A faulty joint can cancel out the benefit of the panel’s good parameters.

The scope of guttering and downpipes must be determined separately. The example given does not price them. The same applies to skylights, lightning protection systems and equipment on the roof. If they are needed, they must be added to the cost estimate and the related penetration details checked.

Let us also assume €810.07 net for installation, €196.73 net for transport and €162.01 net for equipment. The total for the whole example is €3,668.29 net. Converted to 48 m², this is approximately €76.42 net per m². The result covers only the itemised positions.

It does not include a new structure, foundations, installations or the dismantling of the old roof. Tax must be settled in accordance with the actual transaction. Check whether the equipment offer includes an operator and the time needed for set-up. A short job does not always mean a low mobilisation cost.

Difficult access, high-level installation and a large number of penetrations increase the complexity of the work. Long elements require space for manoeuvring. Replacing a roof over an operating room may require protecting the equipment. This is not visible in the price of the panel per metre.

If you are planning several similar buildings, compare shared transport and staged deliveries. Stock on site requires protection and monitoring. A small logistical saving should not increase the risk of damaging the entire batch. The schedule has a concrete impact on cost.

Compare solutions that provide similar parameters and scope of finishing. The variant with single sheeting requires separate insulation and the remaining layers if the interior is to be heated. Comparing the price of the panel with the price of the sheet alone does not describe equivalent tasks.

Add the labour costs at each stage and the subsequent maintenance. Check the possibility of inspecting the joints and replacing an element. The final decision should result from a full quote and the requirements of the building. A single low unit rate does not settle the entire calculation.