In 2025, Permarock proudly celebrated its 40th full year of trading as a registered business. However, its history in the field of external wall insulation (EWI) goes back even further. In this article, we trace the company’s roots as a specialist manufacturer and show how, over more than four decades, it has cemented its position as an unrivalled expert in the field of EWI solutions.
Permarock is one of the UK’s longest-established designers and suppliers of EWI and specialist render solutions. Today, it is part of the Sustainable Investments group, which is led by Derek Horrocks – a key voice of the industry – but it was originally established in 1978 as part of Blundell Permoglaze, a coatings company based in Hull. A brand rather than a separate business at that time, it developed insulated render systems and completed its first major project in Wirral in 1979.
1980s: Growth and Recognition
In 1981, its ‘Thermarend’ insulated render system became the first external wall insulation (EWI) system to be tested and accredited in the UK by the British Board of Agrément (BBA). In the same year, the company became a founder member of the original EWI industry association: the External Wall Insulation Association (EWIA).
An important change occurred in 1984, when Permarock became an independent company. This followed a successful management buy-out led by the late Dr Rodger Canning, supported by friend and colleague Ivor Thomas, who moved its operations from Hull to Loughborough.
In 1987, sustained growth prompted the business to find larger premises, also in Loughborough, and here it invested in additional manufacturing equipment for its renders and adhesives.
By this time, Permarock had become a leading pioneer in the use of mineral fibre external wall insulation on high-rise buildings – a role it has continued to perform ever since. Through this and other work, it grew to become the UK’s leading supplier of mineral fibre external wall insulation. It subsequently consolidated this position by securing the industry’s first BBA certificate for a mineral fibre EWI system.
1990s: Quality and Innovation
Over the course of the 1990s, Permarock developed its product range and quality assurance regime. By 1992, its systems were accredited under the quality assurance standard, BS EN ISO 9001 (or BS5750 as it was then), encompassing production, installation and uniquely technical service. Then, in 1995, its EWI systems were assessed and certificated by the Building Research Establishment (BRE). This included, for the first time, certification for the application of mineral fibre and other systems to timber and metal frame structures.
Throughout the nineties, the business continued to develop its systems and project portfolio, and its products were installed on an increasing range of technically demanding schemes. This generated further growth and, in 1996, Permarock was acquired by the Horrocks Group, a prominent family construction group based in the North-West. Permarock went on to expand its leadership team with the appointment of three new directors: Richard Tocher in 1998, Sean Waldrum in 2001 and Jeremy Richings in 2004.
The 2000s: Investment and Structural Changes
The turn of the millennium saw the start of a period of new investment and business expansion. A key step took place in 2007, when Permarock created additional warehousing capacity adjacent to its existing main office and production facility. This enabled it to cope with increased demand, as did the installation of a new, updated manufacturing plant. This helped to boost production capacity and to improve manufacturing efficiencies. In November of the same year, as part of the Horrocks Group, Permarock was taken in under the eaga plc acquisition umbrella.
Two years later, further consolidating its influential position within the industry, Permarock took full membership of the National Insulation Association (NIA) as a system holder.
2010 to 2019: New Ownership and Evolution
The next decade saw several important changes to the company’s ownership and direction. In April 2011, eaga plc was acquired by Carillion but the time with Carillion was relatively short-lived for Permarock, which was acquired again on 31 August 2012 and became part of the Sustainable group of companies, owned by Derek Horrocks.
By 2012 Permarock had secured Building Research Establishment (BRE) certification for a wider range of its external wall insulation and render systems. In the same year, the company also achieved compliance with the environmental management standard, BS EN ISO 14001 for product design, manufacture and supply.
The following year, the Permarock became a system holder member of the Solid Wall Insulation Guarantee Agency (SWIGA) and to this day continues to promote the SWIGA guarantee to clients on qualifying schemes.
Further developments and approvals followed:
- 2016: Product design data for key systems made compliant with Level 2 BIM and published online at the NBS National BIM Library.
- 2016: Membership of the Supply Chain Sustainability School.
- 2017: Permarock scheme cited as example of best practice in key government/BRE report: “Each Home Counts”.
- 2017: Chairman and owner Derek Horrocks appointed chair of the National Insulation Association Strategic Board.
- 2019: Project collaboration with architect Mikhail Riches, whose energy-efficient new-build scheme in Norwich wins the RIBA Stirling Prize.
2020 and Beyond
From the start of the present decade, Permarock has continued to innovate, to grow, and to build its presence in the industry. In 2022, it acquired more warehousing and storage space in response to growing activity and demand within the sector, and in 2023, it completed an extensive refurbishment of its offices.
Since then, the business has passed other important milestones including:
- 2023: Its Board of Directors was extended to include two long-standing members of the Permarock team – Nigel Watson and Kieran Loftus.
- 2023: Chairman and owner Derek Horrocks was awarded a place on the Climate Champions’ Power List.
- 2023: Permarock supported the establishment of the National Home Decarbonisation Group. Chaired by Derek Horrocks, it seeks to support retrofit installations for all housing tenure types.
- 2024: Permarock successfully delivered systems into all phases of current large-scale funded retrofit programmes.
- 2024: In conjunction with key industry bodies, Permarock played a vital role in developing new guidelines for Roofline Closure Systems, enabling them to be used in PAS-compliant designs as part of publicly funded retrofit schemes.
- 2024: Permarock aligned its branding with the wider Sustainable Investments Group.
- 2025: Permarock secured a full suite of Kiwa BDA Agrément Certificates for its EWI systems.
In 2026 and beyond, the company intends to maintain this momentum, adapting to industry demands and devising new and better solutions to support the UK’s progress towards Net Zero. It continues to invest in new product development, in training for staff and stakeholder partners, and in its own technical capabilities.
Leadership Structure
Coinciding with its anniversary year, Permarock announced a refreshed leadership structure that is designed to support its next phase of strategic growth.
- Nigel Watson moved into the role of Managing Director. Nigel joined the company in 1996 and has played a key role in its operational development.
- Richard Tocher, who has been with the business since the late 1980s, became Sales & Technical Director, further strengthening Permarock’s collaborative technical approach.
- Long-serving leader, Sean Waldrum, who spent 36 years in the business (16 of which were as Managing Director) will continue to support the business in a senior capacity.
Continuing Goals
Considering Permarock’s next steps, Nigel Watson said: “Our ambitions are to continue to grow in a controlled and sustainable manner, while always staying true to our values: doing the right thing, in the right way. With strong leadership, we will keep pursuing the highest quality standards, working with honesty and integrity, and going the extra mile for our clients and partners as a team, because we really do care about what we do and how we do it. In this way, we aim to deliver the very best in innovation, customer service and technical expertise.
“By applying these values, we aim to cement our position as a valued partner to our many existing clients and stakeholder partners, and of course we’ll also be seeking to grow this network steadily over the coming years. Ours is an important mission and we’re keen to take everyone with us on this journey.
“As we enter our next decade, we’ll be building on a long and successful history. Over the last forty years, we have established a proven reputation for technical excellence, outstanding system performance, and industry-leading support. We’ve earned that reputation by delivering high-quality, energy-efficient façade solutions that improve the appearance, performance and sustainability of the UK’s built environment.
“We have grown from a specialist façade systems supplier into a nationally recognised technical authority, having supported thousands of new-build and refurbishment projects across social housing, education, healthcare, commercial and high-rise residential sectors.
“Our mission going forward is clear. We will continue to support the UK’s journey towards safer, healthier and more energy-efficient buildings, combining proven experience with continuous innovation.
“On this journey, we will be accompanied by our sister companies within the Sustainable Investments group. Together, we aim to provide people with warmer, more comfortable homes and to address the five key crises of the modern era: energy, climate, public health, housing and the cost of living. We will also continue to nurture and develop our relationships in the wider construction and decarbonisation sectors, providing support and assistance to specifiers and contractors alike.”
Commenting on Permarock’s 40-year anniversary, owner Derek Horrocks said: “This significant milestone is testament to the dedication of our team and the long-standing trust placed in us by specialist installers, main contractors, architects, local authorities and housing providers. It comes at a time when we’re seeing growing demand for low-carbon construction, whole-building retrofit, and non-combustible façade systems; decarbonisation systems that are effective, compliant and future-ready.
“Our focus has always been on delivering such solutions, together with unparalleled technical expertise. As we look forward, that commitment remains central to who we are as we continue to make a real difference to people’s lives.”
