Lead Roof Corrosion

More about lead as a building material.

Lead roof corrosion.

If the lead sheet is found to be badly corroded it would be prudent to investigate and eliminate the main cause of corrosion and if necessary alter the roof design to prevent condensation before undertaking repair or renewal. Most lead roofs are unaffected by underside corrosion or contain only a small amount of corrosion products possibly as a result of damp conditions when the roof was laid. Correctly laid lead roof greyfriars roofing note the height of steps between bays the rolled joints and adequate overlaps problems. Lead is commonly used for flat roofs because of it s long life and ability to be formed to fit many positions lead must be laid and formed correctly to achieve this long life however.

Zincalume steel in contact with or receiving of run off water from lead is prone to corrosion. Lead and copper are the biggest culprits when it comes to shortening the service life of metal roofing due to corrosion. Lead is the only metal generally considered to be compatible with zinc coated steel but not with zincalume steel or colorbond steel. However some roofs have been subject to severe underside corrosion as a result of on going damp conditions and the presence of carboxylic acetic and formic acids given out.

Hot water discharge pipes should be extended beyond the roof preferably to ground. It protects the insulated wires inside without making the cable too stiff to bend.