Natural Lime Putty for Restoration and New Build Projects

Cornish Lime and Mature Lime Putty

Cornish Lime is very proud of the fact that it was the first business of its kind in the region; with an objective from the outset to manufacture the highest quality lime putty as cheaply as possibly without compromising the product – lime putty; which it has achieved very successfully. Cornish Lime is not a business that was set up simply to make money, it was the result of craftsmen recognising, understanding and appreciating why cement is most definitely not the right material for the care and repair of Cornwall’s vernacular buildings.

The manufacture of lime putty in the early 90’s was carried out by only a handful of companies around the country and the venture was a real gamble at the time for the business, who as building contractors had very little in the way of manufacturing experience to call upon. Even today some fifteen years on, lime putty is a material where many in the building industry do not fully appreciate the benefits that it has, when used in whatever form, in the care and repair of older buildings. Many believe it is used only on listed buildings, however, and mercifully, it is certainly far better understood today by a lot more people than it was back then.

There are plenty of reasons why lime putty should be used on old or ‘listed buildings’ yet very few logical ones that could ever justify the use for cement on these same buildings. For those who may question that statement, we suggest you have come to the right place, as here at Cornish Lime we pride ourselves on the information we make available; all of which has been prepared by people who know and understand the products that we either manufacture or market, underpinned with a craft knowledge of how these historic buildings were constructed.

Using Natural Lime Putty

Lime Putty is not used on its own, (although it is sometimes used neat as a top coat plaster; however this work does call for a much higher level of understanding for the materials and degree of skill in carrying out this type of finish work.) Lime Putty is the binder where the putty is mixed with a suitable sand in the correct ratio to make a lime mortar, lime render or a lime plaster to name its main functions. Lime putty can also be watered down to make a lime wash.

The biggest advantage to be gained from using lime putty in a lime mortar or lime render is its ability to allow old walls to breathe. Unlike cement when it is used in building conservation as it is far too strong, much more impervious and tends to hold moisture captive within walls that have been built in solid form without a cavity (there are many others as well as ‘breathing’ and we hope you will find the answers to these points in the information to be found here on our web site).

A close up of mature lime putty,.

Yes we are a commercial enterprise but we do have our principles and here at Cornish Lime we fully understand that the most important aspect of the sector that we operate in is that of the historic buildings themselves, especially those that may be listed buildings; after all they are far more important than any of us. We are after all, only custodians for future generations, of a superb built heritage that extends the length and breadth of the British Isles and Cornish Lime is doing its utmost in the bigger picture of trying to conserve and preserve that built heritage, nowhere more so than here in Cornwall and the West Country. Find out more about our high calcium lime putty.

6 thoughts on “Natural Lime Putty for Restoration and New Build Projects”

  1. Hi there, hoping you can advise me on what lime mortar product would be suitable as an alternative to skirting, and any suggestions on techniques would be really helpful.

    • Hi Robert

      One way this was done historically was to run an in situ mould of mortar to create the skirting. An NHL mortar or Prompt Natural Cement, or a combination of both could be used to achieve this.

      You could also fill in these sections with a similar mortar as above.

      If you would like to discuss this in more detail please contact us on 01208 79779.

      Kind Regards


  2. hi , i recently viewed a job ,which has been stated to use lime render for repairs and for limewash .
    the building has been painted in exterior emulsion .is there an additive that can be added to the lime wash for better
    adhesion .
    kind regards
    leon .

    • Hi Leon

      Limewash is not generally recommended to be applied over modern paints, limewash ideally needs a porous surface to work correctly and by using additives the benefits of limewash (mainly vapour permeability) can be lost. There is a product called St. Astier Lime Paint, which can be applied over modern coatings, however we wouldn’t recommend it as it will offer very little durability. We do have a range of mineral based paints, which can be applied over bare render and existing paints and these would be far more suitable, the range is under Beeck and the product is called Beeck Renosil.

      If this is something you would like to discuss in more detail, please do not hesitate to contact me.

      Kind Regards


  3. Hi
    I have an old stone cottage that needs repointing and I am trying to work out quantities for lime putty and sand can you tell me the correct mix and coverage for a 25kg tub of putty .
    Many thanks

    • Hi Andy

      Our premixed putty mortars are made with 1 part putty and 3 parts sand (by volume).

      Coverage for repointing is unfortunately impossible due to the variables found with each building (stone type, joint width, depth etc.). As a general rule of thumb we would work on 1 tonne of sand and 10 tubs of putty giving a coverage in the region of 50m2 at 25mm depth. Alternatively we have our premixed mortars ( which would cover in the region of 40m2 at 25mm depth per tonne or 1m2 at 25mm per 25kg bag.

      If you have any questions or need any further information please do not hesitate to contact us.

      Kind Regards



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