Most lead stains can be easily prevented. Lead just needs to be stored correctly or properly treated after it’s been laid. But if you find that your lead has stained, before, during or after installation, this is what you need to do:

Type of stain	Probable cause	How to treat the stain
Light white stains on the surface of the newly laid lead sheet	Newly laid lead has not been treated with patination oil	If the stains are not too severe, they can be removed with a mild acid solution – vinegar or lemon juice work well. Use a nylon brush or very fine wire wool.
Heavy white stains on the surface of the lead sheet	A reaction of the lead to an acid-curing silicon sealant that has been used to fit the lead flashings	If the lead is fairly new, we recommend you remove the sealant. Next, clean the lead (see above), then apply a coat of patination oil. Use a non acid-curing sealant or traditional mortar on the joint that needs to be sealed
Rusty or orange stains on the surface of the lead sheet	Lead sheet has been stored in damp conditions and moisture has been trapped between the sheet	Use our specially developed lead cleaner and restorer and remove the stains with a nylon brush or scourer.
Red stains on the surface of the lead sheet	Run-off from water of copper or other metals on the lead sheet	Use a strong detergent and remove the stains with a nylon brush or scourer. Then dry the lead sheet with a soft cloth and apply a layer of patination oil.