Trinity Primary Academy

TRC was appointed as principal contractor by Barker Associates in May 2019, to carry out specialist sash window restoration works.

Trinity Primary Academy is a primary school located in Bounds Green Road, Wood Green, London. It was built in 1899 by Mitchell and Butler and consists of yellow brick and red brick dressings, tiled roofs, irregular fenestrations, and sash windows that give away its Queen Anne Revival style. It's currently categorised as a Grade II Listed building with Historic England, and is part of the Academies Enterprise Trust.

Nature of the works

As the building was Grade II listed, timber window repairs had to be sympathetic and complementary to the historic nature of the property. Many of the existing timber sash windows were inoperable due to the build-up of decorative coatings, timber degradation, and defective and broken sash window ironmongery, as well as opening mechanisms. The requirement was for the windows to be fully refurbished, repaired and operational as originally intended, but also modified to meet health and safety requirements.

Phase one of the refurbishment of 200 sash and timber casement windows commenced on the area needing most attention: the west elevation of the building. Following the success of phase one, the client team extended TRC’s appointment to continue around the remainder of the building, systematically completing all other windows, door and roof light refurbishments.

This overall refurbishment project included:

• Stripping back the existing paint from the historic sash windows and repairing any decayed timber.
• Repairing glazing as and where necessary.
• Improving the thermal and acoustic containment by installing draughtproofing.
• Repainting windows and installing ironmongery.
• Undertaking brick and stone repairs to the building’s exterior.

This project also required our specialist attention on some specific areas of traditional glazing. This aspect of the project required the repair and refurbishment of all four oriel bay windows and the oriel bay glazed roofs. Completion included the supply and fixing of new safety glazing and hardwood timber roof rafters, along with the repair and refurbishment of the two existing openable roof lights. The supply and fixing of new code 4 lead flashing, with lead wedges, was also carried out and fully pointed with the correct cement mortar at the wall abutment.

Additional detailed work throughout the project included the following:

• Removal of all existing fitted window blinds for refixing upon completion of works.
• Removal and repair of existing window ironmongery, including original mechanical winding gear, solid bar opening mechanisms, locking fasteners, slide bar restrictors, cable restrictors, handles and stays.
• Careful removal and repair of all internal fixed-glazed hopper units, casements and pivot openings.
• Removal and replacement of all cracked and broken glazing, and replacement of the existing Georgian wired-glazing, with 6mm safety glass or 4mm polished plate glass to areas up to 1.2m height from floor level. Where privacy was required, white opaque glass with thickness in accordance with above was used.
• Removal and replacement of all loose and defective glazing putties, and removal of all flaking, loose and built-up paint coatings.
• Exposure of all timber rot and decay ready for repair with Repair Care Systems products, followed by sanding and priming ready for decoration.
• Vertical sliding sashes repaired, refurbished and rehung on new sash cords and weights, and adjusted as needed. Sashes were routed to accept new brush pile weather stripping. New parting beads and staff beads were serviced with brush pile weather stripping where appropriate.
• Final internal and external decoration was carried out using Dulux or Leyland trade paints, allowing for one undercoat and one gloss finish.