Project Overview
This project involved the removal and replacement of an existing flat abutment gutter that had undergone multiple patch repairs. The existing arrangement was leaking and causing internal water damage. As this flat style was not considered suitable, a new stepped lead-covered timber gutter was installed to provide a more durable, long-term and effective weatherproofing detail.
Our Solution
The existing flat, patch-repaired gutter was removed and replaced with a new timber substrate formed to create a stepped profile. This provided a more considered arrangement at the roof abutment and established a suitable base for the new lead covering.
Code 6 lead was used to cover the timber gutter, with the specification selected to suit the length of the individual steps. The stepped construction allowed the gutter to follow the required profile while providing a robust lead-covered finish.
The existing flashing was also replaced as part of the works, ensuring that the abutment junction was renewed alongside the gutter itself. The Welsh slate roof was carefully cut back as necessary to accommodate the new stepped arrangement and allow the leadwork and flashing to be properly integrated with the existing roof covering. The works included a rethink of the outlet detail to one side of the gutter. A timber lined box connected to a downpipe, however a lead gutter was formed allowing the run off directly into a hopper.
Lead Installation and Craftsmanship
Particular attention was given to the formation of the stepped gutter timberwork and the integration of the new leadwork with the surrounding roof. The steps had to allow flow of water but be suitable for Code 6 lead.
In traditional lead roofing, the choice of lead code (thickness) depends on the size and shape of the gutter lining, including its length, width and how it is supported.
Lead expands when it gets hot and contracts when it cools. A gutter lining exposed to direct sunlight can experience substantial temperature changes throughout the year.
- Expansion: The lead gets longer and wider as its temperature rises.
- Contraction: The lead shrinks as it cools.
- Restraint: If the lead cannot move freely, stresses can build up around fixings, folds, joints and corners.
- Fatigue and splitting: Repeated movement can cause the lead to fatigue and eventually split, particularly at vulnerable details.
A thicker lead sheet has greater mechanical strength and is generally more resistant to damage during installation and service. However, increasing the code does not eliminate thermal movement. Correct detailing and adequate allowance for movement are essential.
The Lead Sheet Training Academy set the technical standards for the industry, offering guidance for lead detailing and length and width capabilities of Lead Codes.
The Result
The completed works replaced the previously patched, flat gutter with a more substantial and durable detail. The stepped timber substrate, new lead covering and replacement flashing provide an improved weatherproof junction, while the carefully adjusted Welsh slate roof ensures a neat and effective integration with the existing roof structure. By undertaking a full renovation of the gutter, we can exclude potential ingress issues from this area. We have advised the Client to allow a period of drying out internally prior to undertaking internal damage repairs.
