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How to cut metal roofing when carrying out independent building

Basic rules on how to cut metal roofing and cutting devices applied for different types of roofing material. Peculiarities of Seam roofing and types of the valley.

Metal roofing is widely used as coating for low-rise houses and cottages and for the construction of multi-storey housing with complex shape of the roof. The roof and pitch structures differ, so for proper performance of the installation work it is important to know how to cut metal roofing. Many developers search for something more creative, and they choose house projects with complex roof.

Major features of cutting different types of metal roofing

We cut the metal correctlySheet metal shears with parallel or angled (guillotine) knives and a circular saw are often used for cutting of sheet metal onto strips or workpieces. If there is an issue how to cut corrugated metal roofing, the most reliable option would be using electric scissors. They are designed for cutting painted metal and plastic, and they are convenient for cutting corrugated sheets as well as any uneven surfaces.

Mechanical separating cut is performed by guillotine shears and press shears. Sheet metal parts with non-straight edges are cut using a circular saw.

How to cut metal roofing with circular saw

Circular saw is equipped with electric motor. It can be of different power and depends on the functions of the tool. When selecting a circular saw, the volume of the processed material and its density should be taken into account.

Pay attention to the diameter of the saw blade and bore. Diameter of the bar must match the bore on the saw itself. Saw blades are fixed with the help of an ordinary screwdriver or a special key. A special mechanism allows fixing the motor to the baseplate. Using this mechanism you can change depth and angle of cut. Using special bus, it is possible to obtain high quality longitudinal section.

Additional attachments, which some models are provided with, make it possible to attach the tool to a workbench. This allows improving working with material and receiving sections of required shapes. During operation, the tool does not move but the material does.

Regulations on how to cut metal roofing using a circular saw

  1. Cut the shingles using hand toolsThe tool should be efficient.
  2. The flanges must be of the same diameter. However, their diameter must be equal to 1/3 diameter of the plate.
  3. Washers and rings are fitted evenly.
  4. Before each installation, the tool must be cleaned with solvent. Do not use rubber-based solvent.
  5. Flanges and rings must be clean.
  6. During operation, the body of the circular saw must be installed parallel to the guide and ruler.
  7. The saw is regularly sharpened. For this purpose, special sharpeners are used.
  8. Before you start, check the reliability of the tool fastening.

Cutting metal tiles

If there is a need in cutting metal tiles, its sheets can be cut by hand. Pre-marking is carried out, and each sheet is cut individually. The main condition here is laying a sheet on the sustainable basis before cutting.

For cutting sheets of metal tiles and steel metal panels you can use

  • conventional hand shears for metal,
  • expanded metal shears,
  • a drill attachment for metal cutting,
  • electric nibbler,
  • circular saw with carbide teeth,
  • a fine tooth hacksaw,
  • a jigsaw.

Mechanized cutting of sheets is performed using special nozzles for electric drill. This tool operates in the same way as nibblers and allows for quick and accurate obtaining the metal cut with a smooth edge.

Peculiarities of seam roofing

How to cut metal roofingIf you are intended to make a pitched roof, the best option would be seam metal roof. It is made of sheet or rolled galvanized steel with polymer coating or without it, as well as of various non-ferrous metals (zinc, titanium, copper).

The texture of such roofing sheets can be flat, shaped or in the form of tiles. When installing roofing sheets are attached to each other by rebates, which can be recumbent, standing, single, double and self-locking. Connection type depends on the installation field of sheets. For example, side edges of long steel sheets vertically running to the slope of the roof are secured with standing seam metal rabbets; horizontal stripes of sheets are fixed with recumbent rabbets. The seams may be formed manually or mechanically by means of special tools. The self-locking seams are joined without any improvised means.

Purpose and types of the valley

Valley is one of the roofing units, a kind of an internal angle which is formed at the place of the two pitches. Main purpose of this element is gathering of precipitation.

How to cut metal roofing with circular sawThere are two types of valleys – the bottom and top. The bottom one must ensure the reliability and hermeticity, and the top one mainly fulfills decorative function. Therefore, the bottom valley is made of durable galvanized steel strip that protects space under the roof from water. Its edges are bent so that the water does not run over. And the bottom valley is placed above the cornice.

The open valley is the simplest solution. But it is only possible to use for the roofs with gentle pitch. The closed valley is used on roofs with acute angles between the roof planes. The twisted valley is fully covered by the roof, but some rows of roofing sheets on the adjacent planes are intertwined.

The decision on how to cut metal roofing and selection of the valley type depends on the pitch angle, the roofing material and the shape of your complex roof. 

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