The Guildhall is a seven storey building designed originally to be used as a warehouse between 1899 and 1903. The Grade B listed structure was converted to offices in 1986 and was the first atrium type building in the city.

Natural Cement were contacted by Richardson & Starling who, whilst they were carrying out external refurbishment works to the building, discovered corrosion damage to the existing concrete lintels. Working closely with the contractor and Structural Engineer for the project John Ward of JW Structural of Glasgow, a specification and method statement was developed which included NATCEM 35 repair mortar as the material most suitable to be used to carry out the concrete repairs.

Each of the concrete lintels contained a steel I-beam. Due to the porosity of the surrounding concrete, the I-beams were suffering from corrosion which caused expansion and rusting of the beam and led to deterioration of the concrete lintels.

Working closely with the Structural Engineer it was proposed that the poor concrete would be broken out back to sound concrete and any loose rust removed from the I-beam by wire brushing. Shutters would then be constructed and the NATCEM 35 would be mixed to grout consistency then poured and vibrated into position using a small vibrating poker, to reconstruct the Lintels. Additional reinforcement was also carefully added to supplement the existing I-Beam in order to ensure the structural integrity of the lintel.

The NATCEM 35 repair mortar was then trowel applied to finish the remaining top section of the 

repair once the shuttering had been removed. The repaired lintels were then painted to match the existing architecture of the building.
 

Used for concrete repairs NATCEM 35 requires no grit blasting of the steel, no steel primers, bonding agents or curing agents. The product can be mixed to either a trowlable or pourable consistency and can be applied at any thickness from a minimum of 10 mm which made it suited to this project.

As the product is Natural Cement based and contains no chemicals, it has no additional curing period resulting in the repairs being able to be painted the same day.

Richardson & Starling are Scotland’s largest building preservation contractor and approved applicators of Natural Cement materials. They successfully carried out the repair works to the high standard required on such a prestigious building.

If your company are interested in receiving training on our concrete repair systems or becoming an approved applicator please contact our office on 01226 381133 or email enquiries@naturalcement.co.uk for more information.