Work is due to begin later this month on restoring the leaky roof of Clevedon’s community cinema.
The Curzon cinema has received a £75,000 donation from the Garfield Weston Foundation, taking its fundraising total to £570,000.
Work will start in late February 2020 and be completed in around six months.
The foundation is a family-founded charitable grant-making trust which gives away more than £80million a year to charities across the UK.
The grant has given a huge boost to the Curzon's fundraising efforts to restore the grade II-listed building's roof and save the one of UK's oldest purpose built, cinemas from closure.
MORE: Curzon receives National Lottery grant.
The cinema's chief executive, Susannah Shaw, said: "We are overwhelmed to receive such an incredible gift from the Garfield Weston Foundation, one of the UK's most respected grant making organisations.
"Its gift has now filled us with confidence that the Curzon will be saved for generations to come."
Contractors tenders proved £30,000 more expensive than the cinema originally estimated.
Staff and trustees have worked closely with architects, Dittrich Hudson Vasetti, and contractor, Corbel, to negotiate the costs.
The charity was impressed with Corbel's track record of heritage building conservation.
Ms Shaw added: "This is a major and complex roof restoration project and we have worked hard to ensure we have got the very best value for our local community, as well as selecting a contractor which has the craftsmanship and knowhow we need.
"Our community has raised £121,000 towards this appeal and we know they are behind us every step of the way.
"We feel confident that we can keep the momentum going and raise the final £30,000.
"This amazing gift from the Garfield Weston Foundation couldn't have come at a better moment."
After securing a safe roof, the Curzon wants to raise a further £2million to restore the cinema to its former glory, with plans to improve the seating, install a second screen on a restored balcony and a lift to all floors.
The Curzon is holding a Big Thank You Weekend tomorrow (Saturday) and Sunday.
MORE: Curzon's Big Thank You Weekend.
Free screenings of Paddington and Bugsy Malone will be held at 1.30pm on Saturday and Sunday respectively.
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