MONUMENT RESTORATION & BLAST CLEANING
Gwynedd Council - Penrallt Column Monument, Penrallt, Gwynedd, LL55
Client's Challenge
Penrallt Column and the surrounding war memorial structures had suffered visual deterioration due to long-term weathering, environmental exposure and the gradual build-up of dirt, grime and atmospheric pollutants.
As a monument of significant historical and community importance, Gwynedd Council required a specialist cleaning contractor capable of restoring the appearance of the memorial without damaging historic stone surfaces or eroding fine detailing.
The client specifically required a sympathetic, non-aggressive cleaning method that would lift contamination while preserving the integrity and dignity of the memorial.
Assessment & Planning
APT ICC carried out an assessment of the monument to determine:
• Stone type and surface condition
• Extent and depth of environmental soiling
• Sensitivity of carved and detailed areas
• Suitability of non-abrasive restoration methods
Given the heritage nature of the structure and the requirement to avoid surface damage, soda blasting was selected as the most appropriate method. This provided effective contamination removal while remaining gentle on historic stone substrates.
Methodology
1. Controlled soda blasting set-up Equipment was calibrated to operate at gentle pressures suitable for heritage stonework.
2 .Sympathetic contamination removal
Bicarbonate-based soda blasting media was used to lift ingrained dirt, grime and environmental staining without abrasive damage.
3. Detail preservation and finish control
Care was taken around carved and detailed areas to preserve fine features and avoid surface etching.
4. Progressive elevation cleaning
The monument was cleaned evenly on all sides to ensure a consistent visual finish.
5. Final inspection and presentation check
Visual checks were completed to confirm the memorial was restored to a presentation-ready condition.
Site Access & Logistics
Equipment
• Soda blasting system using bicarbonate-based media
Chemicals
• No additional chemicals were required – soda blasting provided the primary cleaning method
The Results
• Significant visual transformation of the Penrallt Column
• Long-standing grime and environmental staining safely removed
• Historic stone surfaces preserved without abrasion or damage
• Consistent, even finish achieved across the monument
• Strong positive feedback received from the local community
The restored memorial was widely praised during a commemorative ceremony, with many attendees commenting on the improved appearance and presentation of the monument.
