Marine L4 Mortar
A ready mixed natural hydraulic lime mortar suitable for exposed freshwater and saltwater applications above the water level with a refined buff coloured finish.
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More about Marine L4 Mortar
Cornerstone Marine L4 is a dry ready mixed hydraulic lime mortar designed for exposed marine applications above the water level. Among the marine range, the Marine L4 stands out as the lowest strength and slowest setting, yet it enables a more capillary-active and vapour-permeable marine mortar, with a set time of approximately 8 hours at 17°C. Available with two finishes, a coarse buff finish as standard or medium by request.
Engineered with precision, using natural hydraulic lime and natural sands to create a high-performance mortar for freshwater and saltwater applications, allowing for a more capillary active marine mortar with a slower setting time and additional flexibility. Further, a longer open time makes this mortar undemanding to apply and finish. Available as standard with Saint-Astier® NHL5.
Well-suited for fresh or saltwater environments above the water level, where a fast-set is not required, or the project requires the absence of Portland Cement.
- The lowest strength of the marine mortar range
- Roughly 8-10 hours of working time at 17°C
- Features an attractive buff finish
- Contains no Portland Cement
- Contains no synthetic polymers
- Designed for flexibility and an aesthetic natural finish
- No pigments to prevent colour fading
- Maintains the natural colour of the sands
Suitable for external use, where the binder strength is appropriate for the host background or surface.
Relevant for marine building and pointing work applications, including freshwater and saltwater environments above the water level, where tidal washout poses minimal risk. For a faster setting time or for areas submerged underwater, explore Marine LP6. Appropriate for various project types, including conservation or renovation.
While Marine L4 is entirely natural in colour and absent of any pigments, the environmental conditions and curing process will affect the final colour achieved. For colour-sensitive projects, our team can provide guidance on curing methodology.
A 25kg bag will produce approximately 14.5 litres of mortar and fill roughly 1.5m² of joint at a depth of 10mm. The width and depth of the joint will influence this estimation. On-site trials are advised for the best yield indication for your specific project.
Supplied in 25kg polythene-lined and colour and batch-code paper bags for easy identification on-site and palletised for ease of transport, storage, and handling. FIBC tonne bags are also available.
The working or open time of Marine L4 is variable depending on environmental temperatures. Do not use in temperatures below 5°C or above 30°C, or if freezing conditions are predicted within the following few weeks, including wind chill. We always advise following best practices for curing and protecting fresh lime mortars. Protect from adverse environmental conditions, including frost, rain, direct sunlight and drying winds.
Store in covered and dry conditions, protected from environmental conditions, including water, damp or frost and clear from the ground. Always reseal packaging if product is still present.
Always read the available documentation before use. See the Download Documentation section below for more detailed product information, application guidance and datasheets.
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