
Marine P15 Mortar
A ready mixed natural cement, water-resistant mortar for aggressive freshwater and saltwater applications requiring a robust level of durability, reduced risk of debonding and resistance to sulphates.
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More about Marine P15 Mortar
Cornerstone Marine P15 is a dry ready mixed natural cement mortar for marine building and pointing work of water-bearing masonry above and below the water level in aggressive marine environments. One of our most popular marine products, Marine P15, is frequently chosen for seawater and saltwater canals. Available with two finishes, a coarse tan finish as standard or medium by request.
Engineered with precision, using Prompt Natural Cement and natural sands and free of synthetic polymers to create a high-performance mortar which provides an additional level of durability for aggressive marine environments. Featuring no Portland Cement, Marine P15 offers additional flexibility and reduced risk of shrinkage cracking than typical mortars designed for water-bearing masonry but remains remarkably durable. Available as standard with Prompt Natural Cement.
Well-suited for applications in aggressive marine environments, which require a mortar with a medium level of strength but with an accelerated set.
- Our most popular marine mortar
- Features an attractive tan natural finish
- Water-resistant
- Roughly 50 minutes of working time at 17°C
- A speedy set reduces the risk of washout
- No lime equals no need for carbonation
- Naturally sulphate-resistant chemistry
- Highly adhesive to reduce the risk of debonding
- Contains no Portland Cement
- Contains no modern synthetic polymers
- Minimised likelihood of shrinkage cracking
- Can be conveniently mixed with clear seawater
Suitable for external use, where the binder strength is appropriate for the host background or surface.
Relevant for marine building and pointing work applications above and below the water level, including aggressive tidal environments that would benefit from a robust level of durability, reduced risk of debonding and resistance to sulphates. Appropriate for various project types, including conservation and renovation.
While Marine P15 is entirely natural in colour and absent of any pigments, the environmental conditions and curing process will affect the final colour achieved. As such, we are unable to match this product against other materials. 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. Can conveniently be mixed with clear seawater free of biological, silt and sand contamination. 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.
The working or open time of Marine P15 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 natural cement 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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