His Majesty’s Theatre, Aberdeen – one of our finest performances


Aberdeen Performing Arts approached us to replace a damaged roof vent at His Majesty’s Theatre (HMT), Aberdeen which had fallen into a state of disrepair. The vent was over a hundred years old and was leaking water on to a large vintage chandelier above the public seating area. Wind damage and age had taken its toll on the vent, which sat in the middle of a flat roof, forty metres above ground level.

HMT is listed by Heritage Scotland and the brief was to form and fabricate a vent to the exact shape and profile of the one that had to be replaced.

The main obstacle was the size of the cowl and its position in relation to other buildings. The vent was three metres high and two metres in diameter situated on the main theatre roof between smaller buildings, which made it hard to reach.

We surveyed the job along with Plant Shifters, who were to supply a crane to lift off the old vent and lift on the new one.  It was clear the boom of a crane would swing over the nearby railway line and permission from ScotRail was required. To add to the drama, a site survey revealed under several layers of paint that the vent was made from asbestos.


ScotRail agreed to us deploying a large crane near the railway line as long as two of its operators were there to oversee lifting operations. This added to an already tight budget for our client, so we decided to design and build a small portable lifting device to allow us to make a straight vertical manual lift on the opposite side of the railway line. The approach meant the new vent had to be made in several small sections before being bolted together on the roof.

A specialist asbestos removal company cut the old vent in to small sections, bagged and lowered it to ground level using the same lifting  apparatus. Meanwhile back at our workshop, our experienced ensemble of fabricators performed what they do best, replicating the old vent by cutting, rolling, and welding the various pieces ready for assembly by our team on site.


The results are there for all to see – a vent built to withstand extreme weather and sympathetic to the original design in keeping with this historic building in the heart of the city. Theatre-goers can sit in comfort and enjoy the entertainment now the building is watertight and secure; while for our part, we are confident the new vent will last another hundred years. Call James Aiken Engineering Solutions on 01224 704842 for your next fabrication project – we won’t make a drama out of a crisis.