In the first of a new series in which we ask 10 questions of someone involved with one of London’s historic sites, we speak to Martin Stancliffe, Surveyor of the Fabric at St Paul’s Cathedral, about the £40 million, 15 year cleaning and restoration project at the iconic London structure which came to an end last month…

1. What does your job at the cathedral involve? “Advising on all aspects of the care and repair of the fabric of the cathedral, and its setting. This involves devising and leading all fabric projects, major or minor.”

 2. What prompted the 15 year repair and cleaning project? “The perception that the cathedral could reach out more to all its visitors both as a great centre for worship and as a great tourist attraction if it were in better condition and had improved facilities.”

3. How much of a difference has the cleaning and repair project made to the look of the cathedral, both inside and out? “I think it is not too much to say that the cleaning has transformed the appearance of both the exterior and the interior. In particular, the interior now speaks much more clearly of its primary purpose as a great church and a setting for great national services of memorial or celebration. In addition, the programme of repair works in almost all parts of the cathedral has put it into good condition in ways that can be sensed, but cannot  – I hope – be seen.”

4. How many people have been involved? “It is hard to make a count, but the number must run into several hundred.”

5. What trades did the task require and was it easy to source the sort of expertise required? “The various different tasks required a great range of skills, from masons to electricians and scaffolders,  and from expert painters and gilders to conservators. There is a wonderful supply of skilled craftsmen and professionals in this country; but younger people need to be encouraged to understand how creative and rewarding such work is, and to learn the expert skills required to continue to care for buildings like this.”

6. What was the most challenging aspect of the project? “The most challenging aspect was the organisation of the internal cleaning project, which required special techniques and special scaffolding to enable the cathedral to continue its day to day work uninterruptedly throughout the 15 year programme – including having to remove all scaffolding from the interior for the Queen’s Golden Jubilee right in the middle of the project!”

7. Is the cathedral we now see as (original architect) Sir Christopher Wren envisaged it? “No, the interior had already been substantially altered in the 19th century by the removal of the original choir screen, the stripping of paint from all the internal stonework, and the installation of mosaic decorations. However, the atmosphere in the cathedral is certainly closer to how Wren envisaged it than in its gloomy state 15 years ago; and he would certainly have recognised – and welcomed – the radiant quality of light which has been restored to the interior.”

8. Did you make any interesting discoveries about the building during the restoration project? “A building like this is always revealing new things. We discovered much more about how the lower parts of the dome were constructed, and we have understood much better why and how the building moved and settled as a structure over the last 300 years. We also discovered many fragments of the great cathedral which stood on this site for some 600 years before the destruction of the Great Fire, built into the structure of  Wren’s cathedral.”

 9. What’s your favorite part of the cathedral?  “I love all parts of the dome, from the top of the lantern down to its complex foundations on the top of the arches of the nave.”

10. Can you tell us something about St Paul’s that many visitors may be unaware of? “Many people are unaware of the reason why the dome seems so all embracing when you are in the interior. This is because the dome spans right across the whole width of the church,  allowing the aisles to pass through it, unlike St Peter’s in Rome, for instance.”

WHERE: St Paul’s Cathedral, St Paul’s Churchyard (nearest tube station is St Paul’s); WHEN: St Paul’s is open from 8.30am to 4pm (galleries from 9.30am to 4.15pm), Monday to Saturday. Open for worship only on Sundays;  COST: £14.50 an adult/£13.50 concessions/£5.50 a child (6-18 years)/£34.50 a family of four; WEBSITE: www.stpauls.co.uk