Building Construction Handbook, Eighth Edition

2mm lead sheet 50mm high

wood cored

roll, 25mm

wide at base

25mm rebate

for lead nailed

every 100mm

anti-capillary groove

smooth surface decking

or decking plus underlay

overcloak

40mm splashlap

undercloak nailed

every 150mm to top

of roll

Typical provision of wood cored rolls

and drips † detail at junction

40mm splashlap

drip 55mm min.

45

Lead is a soft and malleable material. A skilled craftsman

(traditionally a plumber) can manipulate lead sheet with hand tools

originally made from dense timber such as boxwood, but now

produced from high-density polythene. This practice is known as

`bossing' the lead to the profiles shown. Alternatively, the lead

sheet can be cut and welded to shape.

Timber Flat Roof Coverings -- Lead Sheet Details