Vandals have caused around £15,000 worth of damage to the pavilion being built as a key part of the Hermitage Park redevelopment in Helensburgh.

The building, which requires specialised construction methods and materials to meet high environmental standards, was targeted on Saturday night.

In what has been described as a “shocking” attack, the vandals damaged specialised insulation and equipment designed to keep energy for heating and cooling to a minimum.

The vandals ripped off and tore critical vapour control barriers, compromised all the specialised taping details that join the vapour control barriers together and ripped off and damaged the specialised insulation.

Richard Shields, a directorof Helensburgh-based Stewart and Shields Building Contractors, who are constructing the pavilion, told the Advertiser the building uses methods developed by the Passivhaus Institute in Germany, which requires an exacting quality assurance process.

It is the first ‘Passivhaus’ building in Scotland for commercial use.

The firm has released a still image from CCTV footage taken at the site on Saturday night which Mr Shields said he hoped would at least deter anyone else from trying to enter the site without permission.

Mr Shields said the yobs also damaged the external window sills which will likely result in the windows having to be removed to allow access for repairs, compromising the integrated details carried out internally to ensure the airtightness required to achieve the accreditation.

He told the Advertiser: “Whilst we take all reasonable measure to mitigate the public from entering a building site, we can’t legislate for acts of vandalism both to gain entry and to ultimately damage the fabric of the building which is being constructed for community us.

“Although the images of the individuals are not great, if they are circulated I’m hoping that, at the very least, it may become a deterrent for any potential re-occurrences if they know their images are being captured.

“In addition to this, we have now instructed our security company to install additional cameras in various locations throughout the site.”

Mr Shields said the company hoped to “incorporate these unforeseen additional works within the current timescales” for the pavilion’s completion.

News of the vandalism was greeted with dismay by Fiona Baker, chair of the Friends of Hermitage Park, who are leading the park’s restoration, who described the incident as "shocking" and said she was very upset that the building had been targeted.

Ms Baker said: “I don’t understand why people do these things. What kicks do they get out of wilfully destroying something which they, or their friends and families, might use?

“It’s disheartening because so many people have supported the park project.”

The pavilion is a key element in the much-anticipated £3.6 million project to redevelop the park as a community and leisure site in the Burgh.

The Heritage Lottery fund gave the project £2.33 million various other groups and organisations also contributed, including the Armed Forces Covenant whose £253,000 grant was allocated specifically to the pavilion’s construction.

Friends of Hermitage Park raised £20,000 through community fundraising events.