How do you compare the cost of a metal roof with tiles or shingles?

A supplier may quote per square metre of total sheet area or per square metre of effective cover. Part of each sheet disappears into the laps and does not increase the area of the completed roof. Modules can also be priced individually. Put all three price bases into the same unit before comparing them.

The roof area and the quantity ordered are different measurements. Valleys, hips and cuts increase material usage. Do not apply one waste percentage to every roof. A simple slope and one with several dormers give different results. A sheet-by-sheet layout is a more reliable basis for the comparison.

A Polish catalogue effective from 28 October 2026 lists a 0.50 mm T18 polyester-coated sheet at PLN 36.34 excluding VAT per m² of effective cover and a comparable standard T35 at PLN 39.73. These are approximately €8.42 and €9.21 respectively, using the shop’s conversion on 13 November 2026 of PLN 1 to €0.2317234. The figures apply to those variants, not to every T18 or T35 sheet.

In the same list, the selected cut-to-length tile-effect sheet costs PLN 39.35 excluding VAT per m² of cover (about €9.12), compared with PLN 43.86 for the modular sheet (about €10.16). These historical material prices are not current offers from this website. They exclude delivery and installation. Check the coating, thickness and terms again when obtaining a quotation.

At the catalogue rate, 100 m² of effective T18 cover costs PLN 3,634 excluding VAT. Converting that total before rounding gives about €842.08. This is not the installed cost of a 100 m² roof: the layout might call for more sheets, and neither flashings nor labour have been priced. Keep this materials calculation separate from the works budget.

On a simple slope, long sheets can reduce the number of joints. A relatively light covering may also be easier to handle. It does not give you licence to reduce rafter sizes: the structure must still carry snow, wind and other loads. Any saving in structural timber must be supported by calculation.

On a roof with several intersecting slopes, smaller modules may be easier to cut and move; the result depends on the arrangement of hips and valleys. For a heated workshop, compare an insulated roof panel with separate outer sheeting, insulation and lining. A higher panel price may replace several purchases and some installation work.

For tiles, include edge pieces, ventilation fittings and fixings as well as the field tiles. The weight matters particularly when refurbishing an older structure. Do not assume that every tiled roof calls for the same, more expensive frame: the design as a whole determines what is needed.

Bituminous shingles normally need a suitably prepared continuous deck. Include the cost of that deck and the required underlay. Comparing loose shingles with a complete metal roofing kit gives a misleading result. Price every option to the same stage of completion with a comparable scope of flashings and junction work.

Establish whether the contractor has included stripping the old covering, preparing the substrate, fitting the gutters and completing every flashing. Identify scaffolding, safety measures and waste disposal separately. Some defects emerge only when the old covering comes off. Agree in advance how any additional work will be priced.

Delivery can change the ranking. Long sheets need a suitable vehicle and an unloading plan. Packs of modules are easier to distribute, but their weight still matters. Restricted access or insufficient storage space may require additional handling equipment. The cost delivered to site is more useful than the collection price.

Use the same roof area for every option. List the order quantity, accessories, underlying layers, labour and logistics for each one. Separate prices including and excluding VAT, and compare the validity periods. Record differences in the coating, warranty and expected maintenance as well.

Even the lowest-priced option must suit the pitch and exposure of the roof. An unsuitable covering can cost considerably more later. For refurbishment, establish the condition of the structure and the actual scope of work first. Only then can you compare metal sheets, tiles and shingles as finished solutions.