What does the price of one square metre of trapezoidal steel sheet really include?

An example roof T35 has an overall width of 1082 mm and a coverage of 1035 mm. You multiply the rate for the overall area by 1082/1035 to convert it to m² of coverage. This factor applies to the stated geometry, not to all sheets with a height of 35 mm.

If the price is €8.80 net per m² in total, you will get approximately €9.20 net per m² of covering. This is an example of how the calculation is made. It does not guarantee the availability of a specific variant at this price. The amount does not yet include cut-offs resulting from the roof shape.

A 4 m long sheet has a total area of 4.328 m² and 4.14 m² by coverage. At the stated basis it costs €38.09 net after rounding. Calculating from the rounded price per m² of coverage may produce a slight difference. Check the settlement rules for the whole order.

What matters is the thickness and grade of the steel, the metallic protection, the organic coating and the colour. Profiling is also added to this. Do not compare the price of a sheet with a thin standard coating to a variant intended for a more demanding environment without describing this difference.

A higher price does not guarantee suitability for every application. The coating must correspond to the conditions on both sides of the sheet. The thickness is selected together with the profile for the structure and loads. The quote should clearly separate these characteristics instead of using a single term for quality.

For clearance offers, state the condition of the material. The end of a production run may have full specifications but limited availability of lengths. A batch with damage requires assessment of the specific defects. The price per metre does not indicate what proportion of the purchase will be usable.

Sales conditions may depend on order size, minimum length and type of production run. Unusual lengths can change both cost and lead time. For stock materials, making use of the available lengths is important. A cheaper batch does not necessarily suit the cutting plan.

For several small roof areas, consider the possibility of a combined order. Do not add extra pieces solely to exceed the discount threshold. Any surplus requires storage and may not be needed later. The benefit is assessed at the level of material actually used.

Felt under the sheet temporarily retains some condensation. It needs conditions in which to release the moisture and dry out. It is not full insulation nor a way to repair a leak. Before paying extra, check whether such a mechanism corresponds to the actual problem in the building.

Ask about the preparation of the overlap and edge zones. The solution must limit the absorption of rainwater by the nonwoven. In addition to the price, compatibility with the entire roof cross-section matters. An additional coating does not remove the need to ensure adequate air exchange.

The sheets are accompanied by flashings, fixings and sealants. A structure or suitably prepared substrate is also needed. Transport, equipment and labour have separate costs. If you are comparing offers for the whole job, also check the removal of the old covering and disposal of waste.

Calculation example: 60 m² of purchased material at €10.42 net gives €625.20. If it covers 56 m² of roof surface, the material alone attributable to one metre of that surface costs €11.16 net. Further expenses will only increase this result. This is a consequence of cutting, not a change in the rate.

Send the same specification to all suppliers. State the profile, steel, coating, colour, lengths and number of pieces. Ask for the unit of settlement and the price of the entire order. Note extras, delivery and any unloading separately.

Check the price validity date and the conditions for changing quantities. After measuring, lengths may change even if the overall area remains similar. Before paying, compare the schedule with the roof drawing. The price per metre is a good start to the conversation, but it should not be its end.