Lead Flashings

Kent Lead Flashing Contractors

Kent Lead Flashing Contractors

Kent Lead Roof Flashing Specialists
Ballman Roofing Contractors use lead supplied by British Lead Manufactures (BLM) who have built a reputation for producing quality Lead Sheet.  All rolls are manufactured to BS EN 12588 to ensures thickness consistency.

The consistency enables us to be absolutely certain of its limits and capabilities. The lead sheet is 100% recycled – making it one of the most sustainable products in the building industry.

BLM provide colour coding, relating to the thickness. The thickness of lead selected, depends on various requirements of the lead, size of a single piece, exposure to the elements, restriction by fixing, and so on. The correct code of lead is fundamental to ensuring the lead flashing will be fit for its purpose.

Lead Roof Flashings Expand and Contract

Lead expands and contracts excessively with thermal movement and there are very complex and detailed procedures that must be adhered to, in order to ensure a correct installation is achieved. All lead craftsmen at Ballman Roofing have been trained and practise the guidelines set out by the Lead Sheet Association.

Lead flashings are used in roofing to cover voids and completed sections of roof to give a neat finish.  They are also used as weathering and capping details. Roof details requiring lead include;

  • Porous walls – failing brick work
  • Capping parapet wall – flashing panels often welted to join together allowing expansion
  • Stepped flashings, usually Code 4, 150mm lead cut into brickwork covering soakers
  • Cover flashings used for weathering eaves tiles and abutments that do not have lead soaker details
  • Chimneystack back gutters
  • Ridge roll cappings
  • Hip roll cappings

The code of lead that is most often used for flashings is Code 4, which is blue, but depending on the substrate exposure and requirement of the lead any of the codes above Code 4 may be used. It is crucial to get the thickness of the lead and the fixing method correct due to restriction once installed. If it does not have the room and ability to move freely it will split, therefore failing to accomplish its job of weathering.

Lead Work is a Craft

The maximum length for any flashing piece is 1.5m, irrespective of thickness. The thicker codes can be used for uneven surfaces beneath, areas that need extensive dressing and, wide flashings to cover voids and areas that will be exposed to extreme sunlight.

Lead work is a roofing material that can often get mistreated by installers who may lack the knowledge and experience required. Problems occur through ignorance, often after the work is completed.

It requires an experienced trained installer, who knows the limitations of the lead, as well as the correct fixing requirements. Stepped flashings cut into brickwork for example must be properly wedged on every brick course and should be pointed with flexible lead sealant that conforms to British Standards. If a mortar point mix is to be used it should contain PVA.

The chase should be washed after grinding to remove all dust and the cement should be forced until no more material will compact into the space. This type of conscientious attention to detail is a fundamental part of engineering a long lasting and robust roof structure.