The stately home is undergoing a massive restoration one of the largest current heritage projects in the UK and more than £7.2m of crucial repairs to its badly leaking roof are now nearing completion.
But after work started, heritage specialists discovered that the Georgian ledging on the roof was crumbling away.
Historic England has provided £224,000 to replace more than 90 metres of the ledging that runs around the roofline of the mansion’s eastern front.
Large sections of stone are coming loose, smaller ones have already fallen off and water is seeping in, causing further damage and posing a potential risk to people below.
Sarah McLeod, chief executive of Wentworth Woodhouse Preservation Trust, said: “We were dismayed to discover the cornice was in a much worse state than anticipated.
“Although small in comparison to the vast swathes of roof we have made safe, it was a big hurdle because we had no money for it.
“We needed to act before the £1.1m scaffold facilitating the mansion’s roof work begins to be taken down from May onwards.
“Waiting months to secure grants would have meant re-erecting the scaffold and doubling the budget.”
The trust teamed up with other local charities to raise the remaining money needed to reach the £368,719 target including Freshgate Trust Foundation and Leche Trust.
“We are enormously grateful to all who rallied to the cause, but particularly to Historic England, who donated almost two-thirds of our target sum,” said Sarah.
“We see the organisation as a crucial partner in our huge restoration task.
“It has already awarded us two grants of £30,000 to enable us to draw up plans to develop our Camellia House, riding school and stables.”
Duncan Wilson OBE, Historic England’s chief executive, added: “We’ve been working closely with Wentworth Woodhouse Preservation Trust to help secure the future of this magnificent Georgian building and are passionate about seeing it restored to its former glory for the benefit of generations to come.
“We’re delighted to be able to offer financial aid to fund the urgent repairs, as well as continue to help shape Wentworth Woodhouse’s future in our role as the trust’s expert advisors.”