Consultant Gifford has carved a name for itself as the designer of eye catching modern structures and innovative solutions to thorny civil engineering problems - think of Gateshead's blinking eye bridge, renovation of London's Somerset House, or strengthening of Kingston Bridge in Glasgow.
In contrast to Gifford's boundary pushing work in concrete and steel, the firm's chairman Geoff Clifton (57, 'and lots of fire in the engine yet') has the perfect second job: He is cathedral engineer for Lincoln and Wells cathedrals.
Cathedrals are rare among ancient structures in still being used for their original purpose 800 or so years after they were built. 'They're not monuments or museums but places of worship in daily use, ' says Clifton.
'There are older religious structures, in the Middle East for example, but many have fallen into disrepair and out of use. We don't want the same thing to happen here.'
Keeping Lincoln and Wells cathedrals in working order while preserving them calls for a fine balance between conservation and replacement/ modernisation, Clifton says.
He joined Gifford in the early 1970s after training as a building engineer and, between trying his hand at motorway and marine engineering, he made his mark on the company with pioneering work on the use of precast, posttensioned concrete in hospital construction.
Following a stint in Nigeria, he returned to the UK to open Gifford's Chester office, from where he got involved in the regeneration of Mersey docks for the Merseyside Development Corporation.
It was here that Clifton first encountered 'historical' engineering work in the early 1980s, repairing cast iron bridges. At the same time, Clifton was getting increasingly involved in practice management - to the point where 'I realised I couldn't run major projects and the firm at the same time'.
He homed in on historic buildings, growing Gifford's portfolio of castle and church repair work over the past 20 years. Cathedrals appeal because of their scale and complexity, and the unusual challenges they pose, Clifton says. 'They are a composite mix of different materials and with no movement joints at all. The roofs are large timber buildings in their own right.'
Work carried out at Lincoln since he took up his post in early 2000 has included monitoring cracks in the main walls of the nave and central crossing tower. Though nothing to be alarmed by, the 70m high tower was shown to be rotating and the walls moving cyclically. He is currently overseeing restoration of Lincoln's Dean's Eye Window (see feature, page 19).
Clifton has enormous respect for the medieval masons, as he does for those who make up the contemporary maintenance team, including the cathedral architect, clerk of works, masons, glaziers, conservators, archaeologists and joiners.
'All have their own approach to their work and I have to understand what that is, and not just think structurally.'
Simple calculations are appropriate for medieval masonry and basic structural theory is usually sufficient for the job. 'Knowledge of how materials move is more important than complex analysis, ' he insists.
'You need to understand how the cathedral was built. For example a crack may not be a problem; Gothic arches will crack, but it all depends on how a crack has occurred and where exactly.'