NICOLA ASHURST

Conservation specialist, Nicola Ashurst, was the keynote speaker at the recent Material Evidence seminar in Sydney. Known internationally for her work on the technical aspects of historic building conservation, Ms Ashurst's research at English Heritage in the UK culminated in the English Heritage Practical Building Conservation series. She now heads Adriel Consultancy in Nottingham which specializes in heritage conservation.

How did you become interested in historic building materials?

I originally trained as an architect at the University of NSW and the University of Newcastle. In my final year I worked on an old building: the Walka Water Works at Maitland. I needed some money so I measured up the building for the Hunter District Water Board and my interest took off from there. Seeing a building which had deteriorated and decayed and which hadn't been looked after, I then wanted to find out how it should be cared for properly.

Soon after that, you joined the Heritage Branch at the Department of Urban Affairs and Planning, which later became the NSW Heritage Office.
As the new person there, all the technical enquiries used to land on my desk. I soon worked out I didn't really know all the answers. It was at this point that we set up the first version of the Technical Advisory Group because we obviously needed wider expertise to answer the questions with which we were being presented.

What do you think the attitude to conservation was in the early 1980s?
Conservation wasn't really regarded as "proper architecture". We were trailblazing. We'd been forced into facing all these technical issues by the Heritage Act which said you always had to look at the condition of a building and the economics of looking after it. We were really thrown in the deep end. In retrospect that was a good thing, because now so much of the reality of retaining and re-using buildings really comes down to how you can fix them and how it can be done simply, correctly and economically.

What kind of projects do you enjoy working on?
I love big industrial buildings that somebody else has condemned or a project where someone has said "you can't do it" or "it's not economically possible". They're the challenges I enjoy.

Which projects have had the best results?
Probably those with clients that were either contractors or developers. I've had a free rein as long as I've got everything done within the budget and on time. They're the projects I've been happiest with... Each and every time the clients have been surprised with the results. A small investment in somebody who knows technically what to do and how conservation works on site has resulted in a successful outcome. Not only because of the quality of the building, but the clients have got properties which they're able to rent and sell at higher values than they would have otherwise.

How do you think the situation in Australia compares with the UK?
In England, heritage is not seen as such of a burden as it is here. The "pluses" of old and listed buildings are more appreciated and even sought after. It would be good to see in Australia a better understanding of the whole practicality and economics of conservation. If people could be less fearful of the burden of re-using buildings, I think they'd be surprised at the results and the economic benefits.

You continually stress the need to diagnose the problem and to ask whether the work benefits the building. Why is this important?
One of the reasons why we need to get it right on the building face is to continue to enhance the building's value from an historical point of view. If the conservation is correct, it will be correct from an economic point of view. By tolerating bad workmanship on buildings we're devaluing them. In the future, surveyors who are valuing buildings are going to look at them and say, "That's been very badly done; the facade of this building has been compromised by the work that's been done on it. Consequently, the building is not worth as much as if it had been done properly".

Is it very common to come across a building that has actually been damaged by conservation?
Poor conservation work has been carried out by all sorts of people, often despite the best intentions. Usually, it's because they are trying to do too much. They're looking for a once-for-all solution. They try to repoint everything or replace everything that's damaged, rather than finding the right balance between replacing and retaining. That, I think, is the art of getting it right.

One of the areas in which you have specialized is the cleaning of historic items. Why do we need to clean buildings?
It is usually because soiling on the surface is causing damage to the stone. The second reason is to match in old and new repairs. Finally - perhaps not so much here as in the UK - it has been seen as a great symbol of urban regeneration. It creates a very important symbol in a neglected area when dirty or neglected buildings are cleaned. Often cleaning will reveal details that were lost and often you can see more of the architecture than you could when it was dirty. When you clean, its always a technical decision plus an aesthetic decision.

Cleaning projects should involve analysis of the stone and the soiling. Every time I've been able to do that level of analysis, it's been quite clear that the building would benefit from having the pollutants on the surface taken off. Analysis has also provided essential information regarding the stones constituents, characteristics and condition and hence its susceptibility to damage from various cleaning processes. Analysis is an important step before and after on-site cleaning trails. Only then should a specification be prepared.

If you could give one piece of advice to those involved in conservation, what would that be?
The best advice is to spend as much time as you can getting to know your building. Get as close as you can to the building, even it means a scaffold or a cherry picker, and do as much homework as early as possible. This way, you end up with the right balance of replacement and retention. And, importantly, you end up with schedules of works that have a defined and controllable amount of work and a detailed specification so the project doesn't go off the rails... It makes all the difference in the world and, from the development side of it, takes the fear element out of it. People will know what they're dealing with.