How to choose a lead-free flashing

Klober UK’s Nick King details six things self-builders and their roofers should be aware of when considering lead-free flashing. 

Not all things are made equal, and this saying can certainly be applied to lead-free flashing. From the material the lead-free flashing is made from, to the adhesive backing and how easy it is to apply, through to testing, accreditations and how much wind uplift it can withstand, there are several considerations that self-builders and their roofers should have in mind.

Complex detailing

For self-build projects with complex features and considering speed of application, lead-free flashing provides the perfect solution. Thanks to its easy-to-work-with nature, the product can be applied by hand and is much more suited to detailing, such as saddle flashing.

In addition to clay and concrete tiled roofs, lead flashing alternatives can be applied to metal roofs. It can also be used on existing structures, making it a great solution for both refurbishments and new builds. Lead-free flashing can be used on:

  • Chimneys – the join between chimney and roof tiles can be perfectly finished off with lead-free flashing
  • Roof to wall – providing a watertight solution between roof and wall, such as on an extension or low level roof
  • Solar panels – giving a watertight solution for in-roof solar panel systems
  • Dormers – giving a waterproof connection between dormer and tiled roof
  • Pipes and outlets – can be secured with lead-free flashing and specially designed accessories 
  • Saddles – designed to help weatherproof vulnerable sections of the roof.

Security

When working on any project, roofers and self-builders want assurances that the products they are using will be secure once the work is complete. This is not just in reference to weather conditions, but also the risk of theft. Lead theft is a common occurrence, often on significant buildings such as churches, due to the material’s high resale value.

The risk of theft is reduced with lead-free alternatives as it has no scrap or resale value. For roofers, protecting their work is the ultimate challenge after leaving the site. 

Flashing-alternatives provide roofers with security and knowledge that the products they are using are not going to be stolen by thieves, leading to unnecessary reparatory works.

Ease of application

For roofers, ease of application is one of the major considerations when choosing any material – especially flashing. Many roofers may have previously worked with lead flashing and are well-versed in how to fit the product. So, when it comes to sourcing alternatives, there may be some understandable apprehension.

However, lead-free flashing alternatives are often easier to manage given they are lightweight and pliable. For example, some solutions on the market use perforated release paper and two butyl adhesive strips to help roofers position and apply the product, which if needed can be installed in wet conditions with the use of M-Glue.

In addition, certain lead-free flashing uses self-welding technology, which instantly welds together when overlapped, becoming homogenous and making it impossible to separate. This saves time and increases efficiency as only minimal overlaps are needed and an instant watertight connection is made.

Lead-free flashing allows roofers to carry out the entire installation process while on the rooftop, without needing to use specialist tools. They will only need to go up on the roof once to measure and fit the product. In contrast to lead, where roofers traditionally measure and cut the product on the ground or scaffold, and then get back onto the roof to install it, this process makes it much easier for individuals working independently or on self-build projects.

Wind testing

A common misconception about lead flashing alternatives is that they are not built to withstand high winds in the same way that their lead counterparts are. However, many lead-free flashings typically have self-adhesive properties which means they can withstand tough weather conditions just as well as traditional lead products.

Since lead-free flashing is typically not as heavy as lead, and is self-adhesive, many roofers may think the product will lift in strong winds. However, that is not necessarily true. Some alternatives have been tested in wind conditions up to 114mph, proving it can match its traditional counterpart and stand up to tough weather conditions. Checking the wind testing of a product is a critical consideration for roofers searching for lead-free flashing alternatives that match the hardiness of their traditional counterparts.

Product certifications

Following closely with the point above, manufacturers of high-quality lead-free flashing should be able to share technical guidance around its products, with information including its fire rating, what standard it has been tested to, temperature resistance, and UV stability. 

Self-builders and their roofers can also consider if the product is BBA certified or not. BBA certification shows that a company has gone the extra mile when it comes to product quality and safety.

To meet the BBA’s certification standards, products must endure a rigorous set of tests that demonstrate they are fit-for-purpose. Some lead flashing alternatives have achieved BBA certification and can provide peace of mind for customers giving the knowledge that the product will provide outstanding performance for decades to come.

For roofers working independently, this assurance is second to none and choosing a trusted, tested, and proven product means they can be confident their work will stand for years to come without the need for reparatory works.

Aftermarket support & guarantees

Once lead-free flashing alternatives have been applied, roofers will want to know they have guarantees and support in place in case of any complications or issues. Some lead-free flashing alternatives come with 20-year guarantees, providing peace of mind and security long after the job is complete. 

Before settling on a lead-free flashing alternative, roofers should consider the quality and material composition carefully to ensure they are buying and working with a high-quality product. This goes hand in hand with a manufacturer’s guarantee which signals the product is built to last and can be trusted for years to come.

Nick King is portfolio manager at Klober UK