One of Kent's most historic skylines has been blighted by ugly air conditioning units on top of a new university building, say heritage watchdogs.

Critics claim the equipment has been installed without planning permission on the roof of the new £65 million facility at Canterbury Christ Church University, ruining special views of world heritage sites across the city.

Architect Nick Blake and the Canterbury Society have both complained to the city council and the university.

Mr Blake said: “This is the largest array of hi-tech plant I have ever seen.

“It seems there has been no planning control of these additions by architects or project managers.

“A skilled building designer would have worked with a team of technical experts to ensure that any equipment would have been incorporated into the built form.

“The variety of very intrusive plant that has been installed has wrecked the skyline and extends for the complete length of the building. It is also very intrusive into the whole area including North Holmes Road.”

The rooftop installation on the STEM building, which is dedicated to science, technology, engineering and medicine, is also concerning the Canterbury Society whose architectural advisor Keith Bothwell who branded it an “eyesore”.

“It is a travesty of planning process and I find it quite extraordinary that it has been done,” he said.

“Canterbury is unique in having three Unesco world heritage sites and this is an unacceptable blight on the skyline which is incredibly intrusive.

“It may be very expensive for the university to put right but we will be urging the council to deal with it with the strongest possible rigour.”

City council spokesman Rob Davies says the plant equipment does not have planning permission and the authority is “in discussion with the university about how to resolve the matter”.

"The university appreciates there have been concerns raised by local residents regarding the sight line..."

A spokesman for the university said: “This important new building is designed for science, technology, engineering, health and medicine and represents a significant step forward with our long-term masterplan to provide essential quality education and dedicated research to support our local communities and industries.

“It is a highly specialised teaching environment governed by many health and safety regulations, including fixed unopenable windows to the science and anatomy laboratories.

“Natural ventilation was never an option for this type of building with its complex uses, large quantities of medical gasses, deep plan spaces, and high capacity (2,500 students and staff), so the installed roof top plant is essential.

"The university appreciates there have been concerns raised by local residents regarding the sight line from St Martin's to the Cathedral with one air handling unit within the viewpoint.

“The university always wants to be a good neighbour and recognises the importance of its surrounding heritage and we continue to work closely with the planners at Canterbury City Council.”

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