Useful Information

Rolled (Milled) Lead Sheet to BS EN 12588:2006

There are three different types of lead available for building materials.

  • Rolled Lead Sheet – made by rolling lead through a mill to squeeze the lead to the required thickness. Rolled Lead Sheet milled to BSEN 12588:2006 is the best to use in the construction industry as it provides the most consistent thickness and highest quality product.
  • Machine Cast Lead – made by immersing a rotating water-cooled metal drum into a bath of molten lead. As the drum turns, the lead solidifies on the surface and is peeled off as it emerges wound into coils.
  • Sand Cast Lead – made in small batches by pouring moulton lead onto a prepared bed of sand to a desired thickness

Health and Safety

When using lead sheet:

  • Lift with care – seek assistance as it is a heavy product that often surprises people.
  • Do not eat, drink or smoke while working with lead
  • Wear the appropriate protective clothing, steel toe boots, overalls, gloves etc
  • Apply a hand barrier cream where possible
  • Wash hands and forearms thoroughly before doing other activities

More Information can be found on the Lead Sheet Association (LSA) website.

Health and Safety – Lead Sheet Training Academy

ILA-LeadworkerSafetyDoc2-UK-AW (

How to measure pitch

The angle of a roof is a measure of the underside of the roof from the horizontal as shown in the diagram. If you can access the rafters in your property and can measure the angle it is this angle you are measuring.

The slope of the roof (Pitch) is the ratio of vertical distance (Rise) to Horizontal distance (Run). It can be calculated using a set run of 12” and finding the rise at that point on the roof (See diagram).

The slope ratio (Pitch) can be converted into an approximate angle using the following table for your convenience.

Roof Pitch Angle
1/12 4.76°
2/12 9.46°
3/12 14.04°
4/12 18.43°
5/12 22.62°
6/12 26.57°
Roof Pitch Angle
7/12 30.26°
8/12 33.69°
9/12 36.37°
10/12 39.81°
11/12 42.51°
12/12 45.00°

Left or right hand flashing

Although very simple this sometimes proves confusing depending on where you view the structure from but hopefully this picture will help.

Left and right are as you look at the dormer or chimney breast from the ground. We class the left side as the left hand and the right side as the right hand. We use which side of the structure the product goes on rather than which side of the roof it is on. Sometimes a phone call can help clarify things with awkward and unusual situations so please feel free to contact us.

Soaker Length Calculation

The Gauge is the distance between your roof battens and the Lap is the distance each tile overlaps the one beneath it.

The length of a soaker should be the gauge + Lap + 25mm for fastening if required.