







Fine Putty Mortar & Topcoat Render
A ready mixed multipurpose non-hydraulic lime putty mortar for pointing and general building work or as a topcoat render with a fine texture and refined buff coloured finish.
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More about Fine Putty Mortar & Topcoat Render
Cornerstone Fine Putty Mortar & Topcoat Render is a wet ready mixed
multipurpose non-hydraulic lime putty mortar for pointing and general building work or as a fine render coat. Available in the colour buff.
Engineered with precision utilising non-hydraulic mature lime putty and natural sands to create a high-performance multipurpose mortar and render with a fine finish. Made with our own premium lime putty, matured in our pits on-site for a minimum of 4 months. As a fatty lime with a high free lime content, our non-hydraulic lime putty range is more breathable, porous and flexible than our Natural Hydraulic Lime ranges.
Well-suited as a fine float coat render or projects looking to achieve a
the aesthetic of a traditional heritage lime render.
- Multipurpose use for building, pointing or rendering
- Popular as a fine topcoat with a float finish
- Made with our own four months matured lime putty
- A fatty and workable mortar for those behind the trowel
- High vapour permeability for improved moisture management
- No pigments to prevent colour fading
- Straightforward to use and knock up
Suitable for internal or external use, where the binder strength is appropriate for the host background or surface.
Fine Putty Mortar & Topcoat Render is a suitable for general building and pointing work as well as rendering applications. Suitable for topcoat applications over an appropriately prepared undercoat. Various finishing techniques can be implemented depending on the project’s aesthetic requirements. This topcoat is primarily finished as a float coat, although a sponge coat finish is also applicable. Well-suited for stonework or brickwork applications with joints narrower than 10mm.
Explore Superfine Putty Finishing Plaster for superfine traditional finish. Appropriate for various project types, including conservation, renovation, or sustainable construction. Appropriate for various project types, including conservation, renovation, or sustainable construction.
A 20kg tub yields approximately 10 litres of wet lime mortar or render. For rendering, this covers roughly 1m² at a 12.5mm thickness. For brickwork pointing, this will fill roughly 1.2m², for stonework pointing 1m² at 25mm depth or bedding 0.5m².
Consumption rates will change based on the condition of the background and suction. 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.
As natural products, our natural sands may exhibit variations in colour, texture, and shape. While these variations are minimal, when colour consistency is crucial, we strongly advise each elevation is completed using material from the same batch.
Supplied in 20kg buckets and palletised for ease of transport, storage, and handling. FIBC tonne bags are also available.
As a traditional non-hydraulic lime putty plaster, Cornerstone Fine Mortar and Render hardens through carbonation, a chemical process in which the plaster absorbs atmospheric CO₂. Seasonal climatic variations significantly influence carbonation; external work with this product is inadvisable between September and early April.
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 renders and plasters. 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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