A £1.3million extension to a medieval priory, which has been in the pipeline for more than a decade, is set to be completed by the end of this week.

The Augustinian Friars, who run Clare Priory in Ashen Road, first came up with an expansion plan for their Catholic church around 14 years ago, after the 140-strong congregation outgrew the 90-seat building.

But because of the historical significance of the priory, English Heritage could not reach an agreement on what could be done.

Then just as the friars received news that they could build on the blind side of the old church so it did not detract from the historic value of the building, the project was hit by a further setback when the specialist building firm employed to do the work went into administration, leaving them with an extra £250,000 to find.

Work finally recommenced last July and despite the cold weather, which hampered some of the specialist building processes, the finishing touches are finally being made to the historic church.

Parish priest and prior, Father Bernard Rolls, said: “It has been a long road to get to this point but the end results are going to be stunning.

“Some of the original exterior flint walls are now inside the building and where we were able to break through the original church wall, the arches have been created in Clipsham limestone, which is the same material that would have been used in the original building.

“The dark wainscoting and the gloss paint has painstakingly been stripped off and it has been limewashed as it would have been in medieval times, which has really lightened the whole church. Everyone involved in the building work is thrilled at how wonderful it looks.

“The new part has brought the original back church to life.”

A spokesman for English Heritage said the overall design “enhanced the significance of the site” and was an “excellent example of blending the modern with the old.”

According to Father Rolls, a further £300,000 still needs to be found to pay for the extension.

The annual Clare Priory Craft Fair, which this year will take place on July 13 and 14, is the priory’s main fundraising event.