The Portland limestone Christ Church Spitalfields, a Grade I listed building and considered one of 18th century architect Nicholas Hawksmoor\'s masterpieces, re-opened to the public in September following two years of particularly intensive restoration work.

The church is just 300m outside the eastern boundaries of the City of London, but this was traditionally an area of multicultural poverty and the church was in such a state of decay by the 1960s that there were proposals to demolish it, depriving the East End of one its greatest architectural landmarks, built to cathedral proportions between 1714 and 1729.

Most of the restoration of the stonework has been carried out by Stone Restoration Services of Ongar, Essex, who have also laid a stunning new Purbeck limestone floor

As well as cleaning the interior and exterior stonework, Stone Restoration Services have carried out some major replacement work - such as the parapets - during the six years they have been working there.

The latest, £650,000 phase of their work over the past two years has involved the cleaning, repair and repointing of the portico, repair and restoration of the steps and wing walls, and creating a disabled person\'s entrance in the rectory yard, which involved lifting the existing York stone paving, lowering the ground level, and re-laying the paving. Most of the work, however, was inside.

Most of the internal stone walls are Portland, although as the interior was originally intended to be covered with a shelter coat, the 18th century masons were not too particular about the stone they used. The paint has now been cleaned off and the stone revealed.

Stone Restoration Services also built a new staircase in the vestibules and carried out extensive repairs to maisonettes. Even stone behind wood panelling received attention.

But the crowning glory in its bright, cleaned Portland setting is the Purbeck floor. In the nave the pattern is created from a mixture of Inland Freestone, Downsvein, Pond Freestone and Thornback with Cap for the borders. Cap has also been used for the floors of the upper and lower vestibules.

The stone detail was laid out on CAD by Stone Restoration Services and cut by Purbeck quarriers W J Haysom & Son. And it had to be accurate because a little creep at the start could have amounted to a major error by the time the floor reached the borders. There are around 3,000 individual stones in the floor.

And Stone Restoration Services were not just involved in laying the floor. When they went in the brick floor that had supported wooden boards had already been removed by a demolition contractor, but the brick vaults below had to repaired to ensure they could take the extra weight of the stone floor.

The work on the church has been paid for by some of the largest ever grants given to a parish church by the Heritage Lottery Fund (HLF) and English Heritage. In 1996 HLF awarded the church £2.4million and English Heritage gave it £435,000 towards the exterior cleaning and repairs. In 2002 the church received a further grant of £3.5million from HLF. The World Monument Fund has also been a significant donor and since 1976 the Friends of the church have raised and spent £10million on the building.

The project architect throughout has been Red Mason, first with Whitfield Partners and, since 2001, with Purcell Miller Tritton. The main contractors were Wallis (part of Kier) and the project managers Malcolm Reading & Associates.