SRPM033524-015425 - Cast Stone 25 Year Booklet v2 8 4 16

25th

ANNIVERSARY
1991 - 2016

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Celebrating 25 years

of the

United Kingdom
Cast Stone Association

(UKCSA)

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Contents

Foreword 7���������������������������������������������������������������������������������������������������������������������������
Introduction 9����������������������������������������������������������������������������������������������������������������
History of Cast Stone 11�������������������������������������������������������������������������
UKCSA 15����������������������������������������������������������������������������������������������������������������������������������
Projects 23����������������������������������������������������������������������������������������������������������������������������
Technical 40�����������������������������������������������������������������������������������������������������������������������

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Alan McKevely

First Chairman of the UKCSA

Bill Russell

USA Cast Stone Institute

John Howland

First UKCSA Secretary

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Foreword

A trade association for the UK cast stone industry did not exist in 1990. Other sectors of the building
industry then had very active means of self-regulation, which had contributed towards their growth.
The British Ready Mixed Concrete Association Quality Scheme was one particularly successful
organisation where a former Northern Ireland based RMC manager Alan McKelvey had served on
the National Executive.

McKelvey had resigned from RMC in 1978 to start his own readymix business and later started
Craftstone Ltd. This cast stone business became, and remains, although he has not been involved
for over twenty years, the leading supplier of cast stone on the island of Ireland.

In the USA the Cast Stone Institute had been formed in 1927 as the trade association for the
industry. In 1990 McKelvey contacted the CSI and travelled to New Jersey and Texas to meet with
their representatives. McKelvey invited Bill Russell (right) of the US Cast Stone Institute to come
to the UK and address an informal meeting of representatives of some, but not all, companies
producing cast stone in the UK invited by him.

This meeting took place on Monday 9 December 1990 in the NI Business Centre in Berkeley Street
London because Craftstone were able to have rent-free use of this meeting facility. Ten companies
attended the meeting and another ten companies apologised for their absence.

Those attending listened attentively to Bill Russell describing how the Cast Stone Institute
functioned in the US. After some discussion all agreed that a UK Cast Stone Association should be
set up at a subsequent meeting when those companies, which apologised for their non-attendance
would be invited to attend.

During the meeting John Howland of Broadmead invited Bill Russell to visit their factory in Kent,
which he did before attending with McKelvey his first ever rugby match, the annual Oxford v
Cambridge game at Twickenham. Russell couldn’t believe the players weren’t wearing helmets or
shoulder pads and wore shorts in such an extremely low temperature!

The subsequent meeting was arranged for Wednesday 20th February 1991 also in the NI Business
Centre. That meeting, now recognised as the inaugural meeting of the UKCSA, was attended by
thirteen companies namely Craftstone, Haddonstone, Vobster, Meadowstone, Stepney, Plean,
Malling, Atlas, ECC, Tarmac, Luda, Forticrete and Broadmead.

Elections were held and Alan McKelvey was elected Chairman, John Howland Secretary and Jim
Foster Treasurer.

Subsequent committee meetings were held quarterly in the NI Business Centre until McKelvey
resigned in 1994. A distinguishing feature of these meetings was the adjournment to a local pub for
lunch and conversation between all the members.

A technical sub-committee was set up to consider, in particular, BS 1217 for Cast Stone.

The early days of UKCSA were full of camaraderie and a feeling that together something very
important was being achieved for the cast stone industry. Clearly that happened because now 25
years later UKCSA is celebrating its quarter century achievement.

The next quarter century is eagerly anticipated.

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Andy Cotton

UKCSA Chairman 2006 – Present

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Introduction

In 2016 the United Kingdom Cast Stone Association [UKCSA] celebrates its 25th Anniversary. We
have come a long way from the initial concept which involved a number of UK based Cast Stone
manufacturers seeking to establish a trade body to represent the product in terms of standards for
both technical specification and production controls and techniques together with the aim of raising
the profile and awareness of Cast Stone to designers and architects.

Throughout its history the UKCSA has remained true to the initial goals and is now recognised as the
reference point for information and guidance to the industry on the design, specification and use of
Cast Stone in all aspects of construction. The association has always focused on technical excellence
and then openly shared knowledge through its marketing channels with the aim of raising standards
throughout the industry.

All the achievements would not have been possible without the generous contributions in terms of
both time, commitment, knowledge and expertise of everyone involved in our activities, both Full and
associate members and their respective representatives. This has certainly been the case over the
past decade during which I have had the privilege of being Chair, and I would like to thank everyone for
their help and support – long may this continue to protect and develop the future use of Cast Stone.

Our commitment to quality remains at the forefront of our activities and over recent years, despite
riding the storm of a severe recession,, we have managed protect and update the British Standard
for our product whilst also providing valuable input to related standards in the industry. We have
produced and published definitive guidance on the CE Marking of Cast Stone, providing clarity in a
pragmatic way, on the issue for manufacturers and specifiers alike. Throughout my tenure we have
engaged and maintained dialogue with key stakeholders in the sector including the team at NHBC
responsible for Standards who recognised and acknowledged the benefits of users to specify the
higher standards adopted by the UKCSA and its manufacturing members. In 2013 we introduced
the “UKCSA Quality Mark” to give greater confidence to end users and designers when specifying the
material and manufacturer.

The Association continues to set high standards of compliance for its membership including: the
regular regime of third party accredited product testing; collation of data and presentation of
performance for members on both Health & Safety and Environmental matters; and obligatory
health surveillance for all full member employees. This ensures that not only is the UKCSA the
“Guardian of Quality” for Cast Stone as a product but also that the manufacturing members are
responsible operators who look after their employees.

The years ahead present challenges for the Association and the main objective must be to continue
to strive for excellence in all that we do which will maintain our well deserved status as the primary
reference point for sound advice and guidance on Cast Stone. We should always be open and
inclusive, sharing our knowledge in the hope that the membership will widen and that this will drive
up standards. This will allow what is a fantastic and versatile product to deliver superb projects,
many of which are showcased in this book, with striking architectural design characteristics and
develop its use into the future enhancing the aesthetics of our built environment.

Andy Cotton
UKCSA Chairman 2006 – Current

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History of Cast Stone

Cast Stone products were first produced in the UK in substantial quantities in the late 18th Century
and are still manufactured today and widely used as an alternative to natural stone.

There have been more imitations of stone than any other natural building material. The reasons
for this persistent emulation are various, but have most consistently been for reasons of economy,
availability and fashion.

In the early 18th Century there were a number of manufacturers, for example Richard Holt of
Lambeth, but little information is known about him – although he did publish two patents in 1722.

Some forty years later Daniel Pincot published a paper entitled “Artificial Stone Manufacture”. Pincot
was probably the foremost artificial stone manufacturer of the day. The address shown on the
paper of 1770, is “King’s Arms Stairs, Narrow Wall, Lambeth”. This matched that of Coade of 1769. It
is likely that they worked together for a few years. In 1771, Coade advertised the split with Pincot,
who was no longer employed in her manufactory.

Coade stone is, historically speaking, the most important and significant precursor of the products
that are available today.

The early days for Eleanor Coade were difficult and her Company’s goods faced problems of
acceptability, in spite of the advantages of design, cheapness and ease of manufacture, the building
trade rejected the products as they ran counter to accepted practice.

Today Cast Stone manufacturers are faced with similar problems of acceptability in relation to the
use of Cast Stone for restoration and repair work to old buildings, especially when it comes to Grade
1 or Grade 2* listed structures.

Fortunately, Mrs Coade persevered and the economies and quality of her product prevailed and the
factory became pre-eminent in the early 1800’s as Coade dominated the market.

Even today a certain mystery still clings to the manufacturing process and formula. It has often been
stated that the secret formula of the mix died with Mrs Coade. This is not true.

Coade stone was called by Mrs Coade “Lithodipyra” – which is made up of the Greek works, Litho
(stone); di (twice); pyra (fire). Lithodipyra means therefore ‘stone-twice-fired’. This was here secret
– the mixture contained pre-fired clay (grog) plus fine sand and flint to reduce shrinkage, and soda-
lime-silica glass as a vitrifying agent. Also the mix was fired at higher than normal temperatures
(1100 – 1150c) for as long as four days. This allowed her to produce a wide range of highly detailed
and durable products. Amongst the examples that can be seen today are these Pineapples at Ham
House in West London and the South Bank Lion at Westminster Bridge.

During the 19th Century there were an extensive number of Cast Stone manufacturers – over 25
firms are on record. Stone companies, seeing the potential, started producing their own formulae
similar to Coade terracotta, whilst others used cement based formulas.

Indeed, artificial stone can be separated into two groups; those based on clay formulas that were

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moulded and fired, such as Coade and Blashfield’s terracotta, and those based on cement, which
were cast and hardened without the application of heat. Such names include Austin and Seeley’s
limestone or Pulham’s Portland Stone cement.
By 1850, the Coade factory had been closed for several years and J M Blashfield, H M Blanchard
and J Pulham filled the void with their clay-based products. Also available were the cement-based
products of J Pulham and Austin & Seeley.
By the late 19th Century, the number of manufacturers had multiplied, with production not only
in London and the Home Counties, but also in the Midlands by Gibbs and Canning, in Devon by
Watcombe Terracotta, in Scotland by Garnkirk Company and in the “Potteries” in Staffordshire by
William Baddeley.
The large number of manufacturers illustrates the demand for the product. There were several
reasons for this:
Mass production was relatively cheap compared to carved stone and could be afforded by the
growing affluent middle class. The quality was extremely good and was able to resist the ravages of
the British climate. They had an advantage over cast-iron products, as they were not subject to the
unsightly effects of oxidation.
Relatively little is known of the manufacturers, their formulae and their catalogues. The great
mass of pieces produced, were unmarked and landscape ornaments in particular are consistently
mistaken for natural stone and vice versa.
Indeed, some of the historical substitutes for natural stone are now themselves the subject of
conservation. In fact Cast Stone garden ornaments often command high prices in auction after they
have matured for several years in the natural environment.
Compositions based on Portland cement have been refined over the decades such that most
modern artificial stone is based on the mixture of cement, sand and stone aggregate, hence the
name reconstructed stone.

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Coade Stone

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United Kingdom Cast Stone Association – UKCSA

Timeline

25th October 1990
A meeting of various members of the UK cast stone industry, together with representative ( s?) from
the US CSI, agreed that “it would be a good idea to have an independent association called UK
Cast Stone Association made up of well established cast stone manufacturers”. The initial aims of
an Association were to be to “Rewrite BS 1217 Cast Stone”, “To make architects more aware of Cast
Stone and its uses” and “To set a standard for the industry”. It was also agreed “To have an inaugural
meeting of the UK Cast Stone Association on 20th February 1990”.

10th December 1990
A further, and better attended, meeting was held at the Northern Ireland Business Centre, Berkeley
St, London. This meeting confirmed that the inaugural meeting would be held on 20th February
1990, at the Northern Ireland Business Centre, Berkeley St, London, and a Chairman, Secretary and
Treasurer of the Association were to be elected at that meeting.

20th February 1990
The inaugural meeting of the UK Cast Stone Association took place. The meeting was attended by
representatives from 13 UK cast stone manufacturers, with a further 4 companies apologising for
their absence. Those companies were designated as Founder Members of the Association, and only
Haddonstone and Plean have been Members throughout the whole of the 25 years. Alan McKelvey
(of Craftstone Ltd) was elected as the first Chairman of the Association, with John Howland (Malling
Precast) and Jim Foster (Stepney Cast Stone) being elected Secretary and Treasurer respectively.
The first annual subscription fee was set as £100.

23rd October 1991
CE Marking first raised at an Association meeting.

12th March 1993
New Chairman elected for the Association.
Membership subscription had risen to £350 per year for Full Members and £150 for Associates.

April 1993
UKCSA new “Specifier and User Guide” issued.

22nd March 1994
New Chairman elected for the Association.

June 1994
UKCSA “Specification for Cast Stone” introduced.

December 1994
First UKCSA “Plant Inspection Checklist” introduced.

1995
First “Newsletter of the United Kingdom Cast Stone Association” produced

28th March 1996
New Chairman elected for the Association.

1st April 1996
Contract with Dundee University for the “Partners in Technology” (PiT) project on cast stone commences.

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March 1997
UKCSA involved in the production of BS 1217:1997

March 2000
New Chairman elected for the Association.

Summer 2000
The first UKCSA “Technical manual for Cast Stone” was produced and published.

Winter 2000
Results of “Partners in Technology” (PiT) project published.

22nd March 2001
New Chairman elected for the Association.

2002
First UKCSA “Awards for Excellence” in cast stone competition.

25th March 2003
New Chairman elected for the Association.

2004
The UKCSA “Technical manual for Cast Stone” was revised and re-issued.

22nd March 2006
New Chairman elected for the Association.

June 2006
UKCSA sponsored MORI Poll reveals a strong public preference for cast stone – and that people are
willing to pay extra for the stylish look it adds to their property.

August 2008
UKCSA involved in the production of BS 1217:2008

December 2008
Cast Stone was recognised in NHBC Standards, with an Action Point that cast stone use should
ideally comply with “the higher standards adopted by UKCSA members”.

March 2011
The UKCSA “Technical manual for Cast Stone” was revised and re-issued.

1st May 2013
UKCSA Quality mark scheme for cast stone launched.

February 2014
UKCSA involved in the production of updates to BS 5642 Parts 1 & 2.

February 2015
UKCSA definitive “Cast Stone CE Marking Checklist” published.

24th March 2015
Andy Cotton (GreconUK) re-elected Chair of the Association.

20th February 2016
UKCSA celebrates 25 years as the “Guardian of Quality” for cast stone.

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UKCSA Technical Manual

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United Kingdom Cast Stone Chairman

1990 - 2016

1991 – First Chairman
Alan McKelvey (Craftstone Ltd)
1993 – 1994
Chris Fjaerem (Luda)
1994 – 1996
Alan Lorentzen (Haddonstone)
1996 – 2000
Ged Smith (Redland)
2000 – 2001
Barry March (Vobster)
2001 – 2003
Bob Faulding (NBS Pennine)
2003 – 2006
Barry March (Vobster)
2006 – 2016
Andy Cotton (PD Edenhall Ltd/GreconUK)

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Photo Casebook

A selection of projects completed by
UKCSA members

Scarborough Spa

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Marshes Shopping Centre

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Abford House – Precast

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Robinson Court – St Elphins

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Pear – Cast In Stone

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Crows Nest

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Hanover Square

Bourne Hill Stud

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Weybridge
Southport Fire Station

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Technical

Specifying Cast Stone with Confidence

A guidance note to specifiers and users on the characteristics of cast stone that can influence the
choice in terms of supplier and type of cast stone units.
Cast stone’s clever use of cement and other materials makes it an appropriate and attractive
product for use in both new build and refurbishment projects. It is durable, long lasting and can
match the appearance of many natural stone finishes.
Cast stone is comparable to natural stone as a building material in both appearance and
performance, yet it is readily available and provides a cost effective alternative. It can be formed to
almost any shape and size the designer wishes and can equal or surpass the technical capabilities of
natural stone in terms of strength, moisture penetration, colouring and texture.
Cast stone as defined by UKCSA is “any product manufactured with aggregate and cementitious
binder intended to resemble and be used in a similar way to natural stone”.
The UKCSA has three specific categories of cast stone, determined by a combination of
manufacturing process, technical performance and applications. These categories are described
as: Semi Dry, Wet Cast, and more recently Fibre Reinforced Cast Stone. A detailed summary of the
various categories and processes is contained with the UKCSA Technical Manual for Cast Stone
(Section 2) available as a download from the website.
This guidance note is focused on the issues that a specifier and/or end user may need to consider
when choosing which product to use on a particular project and the categories are listed below with
the relevant points:

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• S emi Dry: This is a “traditional” product made from a low water content mix, compacted into
moulds to a similar density to that of natural stone. Typically the product is demoulded immediately
after casting and there is no need for a secondary surface treatment. The product exhibits a
sandy/grainy texture that is most similar to natural sandstones. Units are produced for standard
masonry construction in traditional sized pieces and profiles.

• Wet Cast: This process uses a higher water content and results in a closer texture and increased
density of circa 10% above that of natural sandstones. Casting will normally be at the rate of one
unit per mould per day. Whilst smooth faces need very little extra treatment, a textured surface,
similar to sandstone, may need a degree of secondary treatment subsequent to demoulding. A
wide variety of finishes is possible and the manufacturing process and mix design is eminently
suitable for the precise creation of fine detail and the incorporation of reinforcement to achieve
specific structural requirements, with the option of larger units/panels.

• F ibre Reinforced: This process incorporates fibre reinforcement into a higher water content mix
that can be either poured or sprayed into moulds, from which the product is demoulded the
following day. A dense product with a close face texture is achieved which can be varied by the use
of secondary surface treatments. Often the units are produced in thin sections which reduces the
weight and associated manual handling issues, and offers the opportunity, through careful design,
and use of fixings for retrofitting to the structure.

All categories have their relative advantages and should be considered as suitable or preferred
alternatives to the natural stone they replicate.

More important than the type of manufacturing process will be the quality of the raw materials,
product durability, buildability, and most importantly the reliability, dependability and accountability
of the manufacturer. Therefore it is essential that, whichever product category is selected, the
supplier should be chosen extremely carefully.

Choosing an UKCSA member company gives the confidence required through the strict controls and
standards adhered to, which include the manufacturing standards and procedures and third party
testing and verification together with the social responsibility expected from a credible organisation.

If you are considering cast stone, think UKCSA, think UKCSA Quality Mark and specify from the Full
Manufacturing Members listing using the UKCSA Specification Document.

British Standards for Cast Stone

The UK has a long history in the manufacture and use of cast stone and in 2015 the original British
Standard for Cast Stone, BS 1217, reached its 70th anniversary, having been first issued in April
1945. Although the standard for cast stone has been changed and improved over the years, BS 1217
remains one of the longest standing British Standards which is still in existence.

The original 1945 version of the British Standard for Cast Stone, BS 1217:1945, required the
compressive strength of cast stone cubes to “be not less than 2500 lb. per sq. in.” This represents a
compressive strength of only 17 N/mm2 (17 MPa).

Since 1945 the British Standard compressive strength requirement for Cast Stone has increased
to a minimum of 25 MPa, and the United Kingdom Cast Stone Association (UKCSA) require its
manufacturing members to achieve a minimum cube compressive strength of 35 MPa. This
represents a minimum increase in strength of 40% over the current British Standard BS 1217:2008,
and over double the strength requirement of the original Standard BS 1217:1945.

Throughout its existence, the United Kingdom Cast Stone Association (UKCSA) has been actively
involved in improving the standards for cast stone, and in recent years in conjunction with the BSI,
and other industry bodies, this has resulted in the production of BS 1217:1979, BS 1217:1998 and

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the current BS 1217:2008 versions of BS 1217. In addition, cast stone products manufactured by an
UKCSA Full Member to the Association’s own stringent requirements and specification have always
been supplied to a standard in excess of the BS 1217 requirements.

British Standards for Cast Stone Sills, Copings and Cappings
The United Kingdom Cast Stone Association was also involved with the British Standards Institute
during 2013 in a complete review of British Standards BS 5642 :Part 1, Sills, and :Part 2 Copings. In
February 2014 the BSI re-issued the two parts of BS 5642, and they now state that Cast Stone sills,
copings and cappings “shall be made in accordance with BS 1217”.

Other British Standards
Other product specific British Standards may exist e.g. BS EN 845-2 Lintels, but it should be
recognised that many of the alternative Standards have performance criteria that fall well below
that set by UKCSA and its members.

UKCSA Quality Mark Standard
In 2013 the UK Cast Stone Association also introduced its own Quality Mark Scheme for cast stone,
which all UKCSA manufacturing members are required to comply with. The UKCSA Quality Mark gives
further reassurance to users and specifiers of cast stone, that the cast stone they are using which has
been purchased from an UKCSA Member is durable, and produced to the highest standards.

Aspects of cast stone which are covered by the UKCSA Quality Mark include:

• Material type: dry-cast cast stone, wet-cast cast stone or fibre reinforced cast stone,
• Compressive strength
• Dimensional tolerance
• Flatness of plane
• Durability and weathering grade
• Freeze thaw resistance
• Bond Strength
• Thermal conductivity
• Resistance to fire
• Acceptability of surface finish

UKCSA Quality Mark for Cast Stone
Cast stone products manufactured by an UKCSA Full Member to the Association’s stringent
requirements and specification are already supplied to a standard in excess of the BS 1217 requirements.

However, the UK Cast Stone Association agreed at its January 2013 Executive Committee Meeting to
introduce its own Quality Mark standard for cast stone, which all UKCSA manufacturing members will
be required to comply with as a condition of their membership.

The Association’s work on the Quality Mark Scheme is now complete and from 1st May 2013 if users and
specifiers of cast stone require further reassurance that the cast stone they are using is durable and
produced to the highest standards, then they should look for the Quality Mark label on the cast stone.

The UKCSA Quality Mark label will only be available on cast stone which has been purchased from an
UKCSA Member. The inclusion of a Quality Mark label on cast stone is the UKCSA manufacturing member’s
confirmation that the cast stone supplied complies with all of the Quality Mark Scheme requirements.

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Aspects of cast stone which are covered by the UKCSA Quality Mark Scheme include:

Cast Stone Manufacturer’s Details
The name and contact details of the UKCSA manufacturing member who is certifying that the
cast stone conforms to all requirements of the UKCSA Quality Mark Scheme shall be stated on the
Quality Mark Label.

Material Type
The manufacturer shall state the cast stone material type, which shall be either dry-cast cast stone,
wet-cast cast stone or fibre reinforced cast stone .

Cube Compressive Strength
The cast stone shall have a minimum cube compressive strength of 35 MPa, which represents a
strength at least 40% higher than the BS 1217 requirement.

Dimensional Tolerance
The dimensional tolerance of the cast stone shall be in accordance with the UKCSA Specification /
BS 1217, Clause 8.1.

Flatness of Plane
The flatness of plane of the cast stone shall be in accordance with the UKCSA Specification / BS
1217, Clause 8.2.

Weathering Grade
The permeability and durability of the cast stone, when tested in accordance with the Capilliary
Absorption Test (CAT) shall not exceed 1.0mg/mm2.

Download UKCSA Guidance Note: Capillary Absorption Test (CAT)

Durability Against Freeze / Thaw
Products complying with these requirements are deemed to be
freeze / thaw resistant.

Bond Strength
In accordance with BS EN 998-2 for general purpose mortar -
the Characteristic Shear Strength is 0.15N/mm2.

Thermal Conductivity
In accordance with BS EN 1745 – λ value for cast stone is in
region of 1.2 to 1.7 W/mK for a 5% moisture content product.

Reaction to Fire
Cast stone products shall be in accordance with Euroclass A1
requirements.

Acceptability of Surface Finish
Acceptability of surface finish shall be in accordance with the
UKCSA Acceptability Guidance Note.

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