Bill Wolmuth studied Civil Engineering at Leeds University and then researched the underlying causes of structural failure, gaining his doctorate in 1980.
He worked for Bovis from 1981-2, and for Mowlem from 1982-96, providing technical support to project teams on building technology related matters, increasingly focussing on the external envelopes of large commercial buildings. Whilst at Mowlem he was also responsible for conceiving, developing and implementing the company’s Technical Guideline system for use by project teams to avoid repetition of technical problems encountered in construction.
In 1996, Bill went to work for STATS Ltd and then in 1998, he established his own consultancy, known as IBT, (Independent Building Technology Ltd) to provide technical support to project teams on the external envelopes of large commercial buildings at all stages of a building’s life, from the conceptual design stage through to Practical Completion and beyond. Since then he has worked on numerous new-build projects and on defect investigations often acting as an expert witness. He has also served on the CWCT’s Technical Committee for more than 25 years.
Q1 – What initially drew you to façade engineering, and what specific aspects of the field continue to fascinate you today?
In 1982 whilst working for Bovis, I visited Josef Gartner in Gundelfingen, Germany to witness laboratory testing of a façade test sample for the Lloyds Building then under construction. It was a pleasure and a privilege, and it sparked in me an interest in façade engineering that no other aspect of building construction could match.
Over the years, I have loved the challenge involved in turning an architect’s vision into reliably performing façades which, despite their slim build-up, have to be buildable whilst being suitably airtight, watertight, wind resistant, fire resistant, thermally efficient and acoustically compliant.
I have also been fascinated for many years by glass technology and was one of the pioneers of glass risk assessments, encouraging Clients’ teams to focus on the glass configurations before they are finalized rather than taking little interest until the glass is on the building. Careful glass specification and procurement can contribute greatly to the appearance of a building and save a lot of tears. I also find glass defect investigations very interesting.
Q2 – How has our approach to façade specification and testing evolved over the years? What aspects have gained importance, and where do you see opportunities for improvement?
At the outset of my career, there were few façade engineering consultants in the UK, no SFE or CWCT, and little by way of weather resistance requirements in British Standards. Some commercial buildings were still being built single-glazed, curtain walling and windows had poor thermal breaks, and there were few unitised façades in the UK. Weather resistance testing was rare and not remotely as rigorous as it is today.
During my career, façade engineering has become a recognized profession and has greatly helped improve the quality of detailed façade design, construction and performance. However, there is still much room for improvement – whereas no building structure is built in the UK without the involvement of a structural engineer, too many buildings are built with no involvement of a façade engineer. I hope that in the years to come that will change and that façade engineering will gain an equal footing with structural engineering on building projects generally.
Q3 – You have a broad knowledge on various façade matters but have also developed specific expertise on aspects such as glass and façade testing. Do you consider yourself more of a generalist or a specialist?
Over the years I have simply responded to requests for technical support. Very often, that has involved getting immersed in aspects of façade engineering and glass technology that others have not been so interested in. I very much consider myself a generalist who has been fortunate to also become a specialist in a few subject areas.
My knowledge of façade testing started with providing technical support on bespoke curtain walling packages where lab testing was essential as the profiles were project specific. That work then helped me apply recognized and ad-hoc water testing methods to identify leakage paths through facades as part of defect investigations on post-construction commissions.
My knowledge of glass technology owes much to having visited more than 40 glass processing companies during my career, some a number of times. On every project on which I provide technical support during construction, I vet technically the proposed glass processing company before they are appointed. Through that, and gaining commissions to investigate glass defects post-construction, I have learnt more and more and gradually morphed into someone thought of as a specialist.
Q4 – You have made a significant contribution to knowledge sharing and collaboration within the Façade Engineering community, is there any message you would like to share with the industry?
It is exceedingly rare for any defect in any aspect of construction to be a ‘state-of-the-art’ problem. In my opinion, more than 99.9% of problems crop up again and again. Such problems normally result from those involved on the projects concerned not having the requisite experience or assuming someone else has a handle on whatever the matter involves.
In light of the above, I consider it incumbent on professionals involved in construction not only to avoid problems but, when they encounter issues that are not covered in Standards or published technical guidance, to feed back discretely the lessons learnt within the company they work for. Where appropriate, feedback should also be given to organisations such as the SFE and CWCT, so that in due course published guidance can be written or amended accordingly. How else is the industry going to improve current practice ?
I dearly wish there was a stand-alone British Standard on formalized information feedback systems within companies (not only in construction) to focus companies on capturing lessons learnt and feeding them back to other staff to avoid repetition of the problems concerned. If there was such a Standard, companies would want to gain accreditation, just as in past years they have done with regards ISO 9001 and ISO 14001. Perhaps there is a counter-argument that such an aim is covered by some wording somewhere in existing standards but if so, it does not seem to be working.
Q5 – Could you describe a particularly challenging facade project you've worked on? What were the key factors that contributed to its complexity, and how did you overcome them?
During my career I have had the greatest pleasure from making a difference on the projects I have worked on, whether it be a new-build, a defect investigation, or expert witness work.
The new-build façade projects I have found particularly challenging have been when working for the successful main contractor from PCSA stage onward and concluding early on that the method of façade construction envisaged by the Client’s team is technically possible but practically undeliverable using available competent supply chains.
There are a number of significant commercial buildings on which my involvement in package design meetings resulted in major changes in the means of achieving the architectural intent. Design teams have tended to be persuaded by lengthy discussion of the design details, followed by supply chains willing to tender for the proposed alternative design but not the design team’s solution.
There are also a number of buildings whose leaking facades I have investigated and overseen successful remediation of. On such investigations, it is crucial to identify all of the leakage paths and not to jump to conclusions when the first one or two such paths have been determined. It is equally important to water test trial remedial works and then bay by bay to avoid completing remedial works only to find that the façade is still leaking.
Finally, there have been quite a few expert witness cases that I have worked on where I have been able to guide my Clients on the technical strengths and weaknesses of their position and of the other Parties. Thus I have been able to help my Clients either to admit defeat or to gain a favorable settlement having secured and considered evidence that they might otherwise have overlooked to their detriment.
Q6 – Reflecting on your impressive work leading to the Lifetime Achievement Award in 2023, which was the turning point in your career that shaped your professional trajectory?
There have been a number of turning points. Firstly, working briefly for Bovis and gaining an insight into a wide range of building technology topics. Secondly, working thereafter for Mowlem where I was able to develop my interest in building technology in general and façade engineering in particular; the experience was invaluable. And thirdly, reaching a point in the 1990s where I felt I should leave Mowlem and do my own thing. Since then, I have never looked back. However, the whole journey started after my A-levels with me studying at Leeds University to whom I owe so much.
Q7 – Could you tell us more about your passion for clocks and how you see it links to your day-to-day work as engineer? Any take-aways from investigating clocks as an amateur horologist?
Everyone needs an interest outside work to take their mind off it. For most people, it is something more mainstream such as playing or watching sport but for me it has been horology.
I have enjoyed over the years restoring numerous mechanical clock movements and their cases, and meeting others interested in horology and those able to help me with repairs when necessary. In restoring clocks I have learnt various manual skills and the importance of patience and persistence.
Working on clocks also kindled my interest in horological history and I have enjoyed the associated research. One strand of that culminated in me collaborating in a long-term project to assemble for The British Museum a representative collection of twentieth century domestic mechanical clocks, and in me co-authoring a reference book on Clockmaking in England and Wales in the twentieth century which documents the final 100 years of mechanical clockmaking in England and Wales, a profession which started in the UK more than 400 years ago.
My interest in horology has twice resulted in me being asked to advise on clocks in towers forming part of facades I have been acting as a consultant on. In each case, I was able to help my Client involve appropriate horological companies specializing in the maintenance and repair of public clocks.
Q8 – Beyond technical skills, what soft skills or personal attributes do you believe are essential for success in facade engineering? How can young professionals develop a strong foundation for a long-term career in this field?
Beyond technical skills, I believe the most important attributes are being able to get on with most people and to communicate well, both in writing and in person.
My advice to young professionals would be, as well as reading and CPD training, use every opportunity in project meetings and in visits to sites and factories to ask questions and expand your knowledge. Throughout your career, keep learning – nobody knows it all remotely.