Disadvantages of trapezoidal sheets on the roof

Trapezoidal sheets are found today mainly in industrial and commercial buildings. On private buildings, on the other hand, they are almost never seen as roofing. Why this is, and what are the concerns and real disadvantages compared to trapezoidal sheets on the roof, read in this post.

steel roofs

Most trapezoidal sheets are made of sheet steel. To avoid corrosion, the sheets are coated several times. The coating is so effective that many manufacturers give up to 10 years warranty on the roof sheets.

Although there may still be a risk of crevice corrosion and contact corrosion, as a rule they can be excluded by constructive measures. Rusting is therefore virtually impossible for a long time.

Only in coastal locations should one be more cautious due to the increased corrosion tendency of exposed metals.

Trapezoidal sheets made of aluminum

Aluminum is slightly lighter than sheet steel and does not tend to corrode. However, the risks for gap and contact corrosion also exist with aluminum. High-quality coated sheet steel is not much more susceptible to weathering corrosion than aluminum.

price situation

Especially with older buildings, where a roof renovation can represent an unreasonable financial burden, the use of trapezoidal sheets for roofing is worthwhile. With a little skill and the right instructions, you can even install them on existing roof battens and rafters, thus saving costs for the expensive roofing performance. However, you still have to bear the cost of scaffolding.

Compared to other roof coverings, such as roof tiles or concrete tiles, trapezoidal sheets are a relatively inexpensive way to cover a roof. The costs can be (without installation) at even less than 10 EUR per m².

Can be mounted usually directly on the existing roof structures. Only the batten distances may need to be adjusted in some cases.

Especially in buildings where the attic is not used, and thus no roof insulation must be made, it is well worth it. In conjunction with a roof insulation, numerous other costs arise, which can then significantly increase the cost.

roof sounds

The rainy sounds on a tin roof are often exaggerated. Basically, the bursting of raindrops on metal roofs always produces noise - but the same sounds also occur when the rain hits a skylight.

A roar of the sheets can not occur with sufficient attachment. The rain noises in an unused attic are not particularly significant. In the case of an attic used as a living space, the insulation then absorbs a large part of the noise again.

Disadvantages in the overview

  • often not fitting to the style of the building
  • is not very high quality
  • Danger of corrosion (after a few decades)
  • slightly louder noises when not insulated (areas used as living space must have roof insulation according to the EnEV)
  • Insulations may be a bit more complicated to install

Overall, the disadvantages compared to the cost advantages are not so difficult. In most cases it is the less promising appearance that prevents many from using trapezoidal sheets. Profile sheets with pan profiles can not be a much more expensive solution.

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