Lime mortar repointing in Co Durham & Nth Yorkshire
A photo of myself and my ever-faithful companion, Doris the Jack Russell.
I have spent the last two decades living and working in Oxfordshire as a lime mortar specialist. I have worked hard to develope an in-depth working knowledge of building limes and heritage plasters and have now brought this home to the North East.
During my time "in the lime" I've also renovated historic stone and brick properties in Northamptonshire, Wiltshire, Berkshire, Gloucestershire and Buckinghamshire.
The sum of my experience as a building conservator now results in the fact that I rarely use anything other than quicklime for my lime mortar. The quicklime comes from Buxton in Derbyshire and I slake it on-site with a special blend of local sands which give it that very traditional distinctive creamy colour.
I also mainly use quicklime because of research highlighted by organisations such as Historic England.
https://historicengland.org.uk/research/current/conservation-research/materials-and-techniques/
In short, when quicklime is used to make mortars for period properties it forms the most attractive, porous and flexible mortar. It's better than any natural hydraulic lime (NHL) or lime putty and it takes a lot more skill to mix, apply and finish.
When mixed with water or damp sand the quicklime starts to slake. The result of this exothermic reaction is boiling lime. This is the only product truly suitable for period properties because it was with this that they were originally built and pointed. What is used today by most contractors is NHL. This is not appropriate because it's simply too hard for old stone. It's also subject to progressive strength gains which means it will, at some point in it's life, trap moisture.
Contrary to popular belief, nearly all traditionally built stone properties were not actually built with mortar made from sand and lime. They were, in fact, built using mortar made with nothing more than earth and lime (and perhaps a bit of straw). This was then pointed with lime mortar. Ergo, the lime mortar you see on the outside of your house was only pasted over earth mortar bedding mortar to protect this erodable mortar from bad weather.
Often, on closer inspection, you'll see white lumps of unslaked quicklime. It's therefore very important to use this same quicklime if you're looking to repoint. The earth/lime mortar - otherwise known as common mortar - is soft and can be washed away by bad weather. This is why the trend of cement pointing became popular. We now know that this is very damaging to older houses.
We now understand that a good lime pointing mortar over the top of earth mortar is essential as it keeps it dry. Lime mortar will also flex with the seasonal movement which all period properties go through during the year. In direct contrast, cementitious mortars are inflexible. Inappropriate mortars also hold back moisture leading to damp and mold.
The above property is one I refurbished using hot mixed mortar in Bledington in the Cotwolds. The mullioned windows were also in need of sympathetic repair. A combination of specialist surface repair mortar and organic pigments and ochres made this possible.
Although the cottage is very old, the windows were even older because they were reclaimed when the property was originally built. It's possible that this stone could date back to the 1400s.
For more on common mortar and lime pointing, click on the above link.
A little about me: I regard myself as a heritage conservation mortar specialist. For practical purposes, and as a service to my clients, I use only the best lime. That is to say, that which has the highest free lime content and the lowest compressive strength. These are much kinder to natural stone and aged brickwork and present the best finish.
Below: a before picture of inappropriate workmanship with cement and rotten quoins.
After: one often discovers that when working on period properties there is a host of other issues which accompany the repointing such as rotten or damaged quoins, cills and lintels. In this case a blend of my own stone repair mortar ensured this property's longevity for many more years.
Littlemore gable repointed using quicklime mortar
My tools and equipment are top quality and I achieve an outstanding finish by increasing the amount of time spent on every aspect of the work including the most important final brushing. I never rush my work; I never cut corners.
An example of this is the photo below which is of personally specified blacksmith forged stone axes. These do a far superior job than ordinary mason's stone hammers.
Most period properties have suffered the damaging effects of unqualified and inexperienced workmanship coupled to the use of inappropriate materials. I see it all the time. The lure of cheap work is not without its consequences and the built environment has, and is, taking a hammering. Please, please please: The time for this to end is now. Have it done right and do your property, yourselves and future generations a favour.
A little history: The ways of preparing mortar were originally passed down from father to son, or master to apprentice, hundreds of years ago. Unfortunately these recipes were misinterpreted during the 80s lime revival. It now means that the current approach to NHL and lime putty is historically incorrect in relation to the way things were done hundred of years ago.
This realisation occurred after old mortars were deconstructed where it was revealed that most were made from quicklime. We now know that the old mortars had a far higher lime content than we ever imagined. The fact is, quicklime expands in volume when water is added making sure that the amount of lime in a mortar mix is increased.
Through many years of practise, in combination with the study of academic research, I can at last bring true historic artisan craftsmanship to period stone and brick built properties using the same high free lime content mortar which I mix hot by using quicklime.
This is made in-situ and the result is slaked lime the same way it was done hundreds (even thousands) of years ago.
I work with my hands, my mind and my heart and have learned over the years that the best quality materials are the only way forward.
What you get from me is the highest quality. When like-for-like craftsmanship is required, that is what I provide.
I have two decades of experience of dealing with grade two listed buildings and other ancient and historic properties.
My focus is primarily on exclusively built properties in prime locations where I can provide quality to owners who are looking for superior workmanship. My customers have usually concluded that to do a good job sympathetically takes time and are unwilling to settle for anything other than the absolute best.
The fact is, for beautifully textured natural stone and brickwork to retain its lasting appearance it needs a quality natural mortar to keep nature at bay. I specialise in the restoration of high-end stone and antique brick properties
Choosing someone who fails to understand the mechanics and science of older properties can have disastrous results as specialist skills and materials are required on historic buildings. These resist water penetration whilst remaining porous and flexible. Moisture is wicked away from buildings ensuring they remain weatherproof, watertight and dry.
In the case of repointing, newly mortared joints often need to be brush finished and not trowel finished. This technique reveals the grains whilst creating a protective coat which weatherproofs the mortar until completely hard
I also work with natural cement ((opus caementicium) which, once combined with lime hydrate becomes ideal for repointing, plastering and stucco work.
Natural cement was patented back in 1796 by the Rev. James Barker. It's made to the original recipe and has had nothing added and nothing taken away. It's vapour open in nature and is simply crushed, kilned and air slaked gault stone. It's uncomplicated, breathable, flexible, natural hydraulic cement which is desirable for its long term durability. However, it is much softer than Ordinary Portland Cement and its porous nature means it is ideally suited to heritage property as its qualities are the same as NHL. Its strength can be increased or decreased depending on the nature of the work and the environment.
I always try and preserve the external fabric of a building and somtimes use specialist products such as Lithomex.
It's a favourite as it allows for complex sensitive repairs to intricate brick and stonework.
I also do lime plastering but these days tend to focus more on insulating lime plaster. It's exactly the same as traditional haired lime plaster but some of the sand is swapped out for materials such as hemp, perlite and/or pumic. It doesn't have to be expensive and the thermal additions enable thick layers of plaster to be applied without the need for PIR board such as Celotex, Kingspan and insulating plasterboard.
Below: ground pummice for insulating plaster.
Perlite for insulating plaster.
My repertoire of sympathetic products also contains crushed chalk and hemp shiv which is used where insulating lime plaster is required.
I also use pozzalana when necessary i.e. if conditions dictate or if a stronger compressive strength is required due to possible damage from severe weather or cracking.
For high end work I include the use of marble dust in my plasters. I also use lime hydrate as academic papers now reveal that its heritage credentials are much more than were considered a few decades ago.
If you wish to give your property the finest treatment in order to keep it optimally maintained then please call for a free no obligation written quotation.
Whilst I work for you, you will have the benefit of my knowledge of period properties which earned me a college lectureship in the further education sector.
A little about me:
I originate from the north of England and am an out-door man. I'm most happy in isolated rural environments where craggy fell-sides drop down to rivers and streams which meander along glacial valley floors. I was schooled in the county of North Riding and have an Honours degree in psychology from the University of Reading. In addition I also have a PGCE from Westminster Institute of Education of Oxford Brookes University. This has enabled me to work in the further education sector where I've lectured mainly in psychology. I also have professional qualifications in horticulture, landscape and design and I've worked in the City of Oxford as an English tutor.
I have applied my scientific background to the study and understanding of the mechanics of traditional building and restoration techniques and now specialise in heritage brick and stone repointing and repair as well as traditional lime plaster.
I have worked to a sufficiently high standard to enable me to be considered for work on National Trust properties. My preference, though, is for privately owned stone or antique brick properties to which I can employ my skills as an artisan craftsman working sympathetically to a high standard.
I'm a straight talking and direct Yorkshireman from whom you can expect honesty and integrity.
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Lime mortar repointing Darlington, County Durham, Richmond on Swale, Yorkshire Dales, North Yorkshire Moors, Leyburn, Hurworth on Tees, Hornby, Northallerton, Stockton, Great Smeaton, North Cowton, Great Ayton, Hutton Rudby, Bedale, Staindrop, Barnard Castle, Reeth, Melsonby, Yarm, Sedgefield, Brompton on Swale, Egglescliffe, Heighington Village, Scorton, Middlesbrough, Teeside, Middleton in Teesdale.
Below: the feet of a man who's "in THE LIME".
