Roundtower Marine LP8 Mortar
Roundtower Marine LP8 Mortar is a ready-mixed natural cement mortar developed for building, bedding, and pointing masonry in marine and water-bearing environments. Manufactured using Natural Cement and selected natural sands, it provides rapid strength development, excellent adhesion, and resistance to washout in damp, tidal, and submerged conditions.
Marine LP8 is specifically designed for softer historic masonry where compatibility is critical. Its lower compressive strength makes it particularly suitable for conservation projects, traditional stonework, and heritage structures exposed to coastal, tidal, or freshwater environments.
Technical Data
| Property | Value |
|---|---|
| Product Type | Ready-Mixed Marine Mortar |
| Binder | Natural Cement |
| Aggregate | Selected Natural Sands |
| Colour | Natural Tan |
| Application | External |
| Workability Time | Approx. 50 Minutes at 17°C |
| Yield | Approx. 14.5 Litres per 25kg Bag |
| Coverage | Approx. 1.5m² Pointing @ 10mm Depth |
| Compressive Strength | Approx. 8 N/mm² |
| Fire Rating | A1 |
| Standard | BS EN 998-2:2016 |
| Packaging | 25kg Bags |
Key Benefits
Low Strength for Historic Masonry
Designed for softer stone and brickwork where stronger mortars may be unsuitable.
Water Resistant
Suitable for masonry exposed to:
- Saltwater
- Freshwater
- Tidal action
- Wetting and drying cycles
Rapid Set
Develops strength quickly, helping reduce the risk of washout in exposed conditions.
No Carbonation Required
Hardens hydraulically, allowing use in permanently damp and submerged environments.
Sulphate Resistant
Suitable for coastal and marine environments exposed to aggressive salts.
Portland Cement Free
Contains no Portland cement, synthetic polymers, or pigments.
Typical Applications
| Application | Suitability |
| Historic Coastal Masonry | ✓ |
| Heritage Pointing | ✓ |
| Tidal Zone Masonry | ✓ |
| Harbour Structures | ✓ |
| Lock Walls | ✓ |
| Canal Structures | ✓ |
| Water-Bearing Masonry | ✓ |
| Coastal Conservation Projects | ✓ |
| Submerged Masonry Repairs | ✓ |
Why Use Marine LP8?
Marine LP8 is designed for projects where compatibility with historic masonry is more important than achieving high compressive strength. Its lower strength helps reduce the risk of damaging softer masonry while still providing the durability, water resistance, and rapid set associated with Natural Cement mortars.
This makes it particularly suitable for conservation work in coastal, tidal, and water-bearing environments where stronger marine mortars may be inappropriate.
Installation Overview
1. Surface Preparation
Substrates should be clean, sound, and free from loose material.
2. Mixing
Mix with clean water or clear seawater free from biological contamination, silt, and sand.
3. Application
Suitable for pointing, building, and bedding in marine and water-bearing masonry applications.
4. Protection
Do not apply below 5°C or above 30°C. Protect fresh work from frost, heavy rain, direct sunlight, and drying winds.
5. Storage
Store dry, covered, and protected from moisture and frost.
