But it was less of a dilemma for Kent-based Adeva Home Improvements because, as Director Geoff Dwyer explained, the backing of the Glazerite UK Group as well as VEKA was crucial in tackling the job.
"We might otherwise have had serious doubts about taking in on," he said after completing the installation of nearly 3,000 windows and doors as part of a £2.2 million refurbishment of Wandsworth's Wimbledon Park Estate.
"But Glazerite was with us all the way. We've been working with them for about six years, and VEKA much longer. We knew the product and the customer service. Glazerite were very supportive; they were up to speed on manufacture and delivery and, just as important, if any problem arose, they would be there to rectify straight away."
The job was not without challenges, he continued, firstly in removing the original Crittal steel frames, which were not only set into concrete but many had to be taken out in a single three metre by two metre piece.
Also the new frames were an unusual combination of side-hung casement and tilt/turns which might have been a problem for some fabricators, though Glazerite took them in its stride.
Adeva installed the A-Rated, SBD specification windows and doors based on the VEKA M70 system, in white for main contractor Mulalley and Company Ltd of Woodford Green on behalf of the London Borough of Wandsworth. VEKA also carried out the wind load calculations for the design specification.
Geoff Dwyer concluded: "This was a very substantial piece of work, and by far our biggest contract to date. But we may well have had to think twice about going for it if it had not been for the support we got from Glazerite"