SODA BLASTING HERITAGE RESTORATION

St Fagans National Museum of History - Cardiff, South Wales, CF5

Soda Blasting and Heritage Restoration at St Fagans National Museum of History of Wales, Cardiff from APT ICC

Client's Challenge

St Fagans National Museum of History required a safe, conservation-led solution to restore a historic fireplace flue within Cilewent Farmhouse. Over centuries, the internal flue surfaces had accumulated tar and resin deposits, creating a potential fire risk and negatively impacting the usability of the historic feature.

As this was a heritage environment, the removal method needed to be sympathetic to the original stone and brick lining, avoiding damage, erosion, or unnecessary disturbance to the historic fabric of
the building.

Assessment & Planning

APT ICC completed a full assessment of the fireplace flue to confirm the nature of contamination and the condition of the stone and brick lining. Due to the high-risk nature of historic tar/resin build-up, the cleaning approach required approval from conservation architects and museum stakeholders.

A trial section was completed to demonstrate that soda blasting would remove organic contamination without damaging delicate heritage substrates. Following successful testing, the methodology was approved for full works.

    Methodology

    Soda blasting was selected because it provides a controlled, non-abrasive cleaning method suitable
    for sensitive stonework. Using bicarbonate of soda as the blasting media, the process safely removed historic tar
    and resin build-up while preserving the underlying substrate.

    Prior to blasting, the room was prepared by carefully moving furniture and sealing the fireplace opening using a temporary framework and taped edges.
    This ensured that residue and debris generated by the cleaning process remained contained and could be safely collected.

    Cleaning was completed across the full 25-metre run of the flue over a three-day programme.
    All waste material was brushed and vacuumed into designated waste containers for compliant removal from site.

    Sodablasting & Stone Restoration at St Fagans National Museum of History in Cardiff

    Site Access & Logistics

    Key Constraints at St. Fagan's National History Museum of Wales
    Coordination at St. Fagans National History Museum of Wales, Cardiff
    Work Schedule at St. Fagan's National History Museum of Wales
    Waste Management at St. Fagan's National History Museum of Wales, Cardiff
    Sodablasting & Stone Restoration at St Fagans National Museum of History in Cardiff

    Equipment
    • Specialist soda blasting unit with controlled air supply
    • Portable lift access equipment
    • Industrial vacuum and containment / sealing materials
    • Hand tools for waste handling and detailing

    Chemicals
    • No liquid chemicals were required for this project - soda blasting media (bicarbonate of soda)
    was used as the primary cleaning method

    The Results
    APT ICC successfully removed the historic tar and resin contamination from the internal fireplace flue without causing damage to the stone and brick lining. The controlled non-abrasive cleaning method restored the flue to a cleaner, safer condition and reduced the risk associated with combustible deposits.
    On completion, the working area was fully cleared, equipment demobilised, and furniture reinstated.
    The restored room was then returned to the museum for public use.