- Designed for lead-masonry and lead-brick pointed work.
- Avoids problems of cracking and lack of adhesion associated with mortar joints.
- Gives a permanent, flexible and waterproof joint.
- Cleaner, quicker and easier to use than mortar, with high adhesion to both lead and masonry.
- Neutral cure product; an acid cure will give rise to white stains on the lead.
- Life expectancy of 20 years.
Flashpoint provides a preferred alternative to the use of mortar as a pointing material for lead-brick and lead-masonry joints. Mortar is unable to expand and contract with lead and masonry during temperature variations, leading in some cases to the mortar cracking and allowing ingress of water.
Flashpoint is a one part, silicone based sealant that once applied will cure to give a flexible, durable and elastic seal, capable of accommodating the high degree of thermal expansion and contraction often encountered with lead flashing exposed to direct sunlight.
Because of its water content, mortar cannot be applied in cold, frosty conditions. However, Premium Flashpoint with its large service temperature range can be used at temperatures down to -65°C.
ADVICE ON USE
- The minimum depth of the sealant injection is 10mm, but in the majority of situations the mortar in a joint should be removed to a depth of 25mm.
- Ensure all mortar is removed from the masonry and lead faces to be sealed by Flashpoint.
- Ensure that joint is completely dry and free of dust before applying sealant.
- Cut the plastic nozzle to an internal diameter suitable to the height of the joint and such that it allows sealant to fill its full depth.
- In order to obtain a professional finish, smooth the face of the Flashpoint joint with a dampened pointing iron before the sealant has skinned over.
- Premium Flashpoint is not an adhesive and is not recommended for joining lead to lead.
JOINTS WITHOUT A DPC
- Turn lead sheet into a joint or chase to a depth of not less than 25mm and secure with wedges or clips.
- Lead sheet folded into wide joints over 18mm cannot be fixed by wedges or clips. Turn up the sheet at the back of the joint and fix with stainless steel screws and washers at 450mm intervals.
- Ensure any space in the joint behind the sealant is plugged with a suitable gap fill product, allowing a depth of at least 10mm for sealant.
- Introduce sealant. To complete the outer layer on a wide joint, cut the sealant nozzle at an angle and apply sealant to top and bottom of the joint before filling the centre.
HEALTH & SAFETY ADVICE
- Keep out of the reach of children.
- Avoid contact with skin or eyes. In case of contact with eyes, rinse with plenty of water and seek medical advice.
- When working with lead, follow standard health and safety procedures as laid out in Control of Lead at Work Regulations 2002.
- Always wash hands well before eating, drinking or smoking.
- Remove lead residues from skin after working with lead metal by washing with Premium Metwash – Soap and Bodywash.
PRODUCT DESCRIPTION AND PROPERTIES
Shore A hardness: 25 (approx.)
Base Composition: Silicone rubber
Shelf Life: One Year
Appearance: Ductile paste
Tack free time: ≥30 minutes – dependent on temperature
Cure period: 3mm depth – 1 to 3 days; 10mm depth ≤14 days
Maximum movement capability: ±25%
Service temperature range: -65°C to 165°C
Performance life expectancy: At least 20 years, if installed correctly
Coverage: A 310ml tube, extruded into a 6mm x 12mm joint, will point approx. 5 linear metres.