Drones & Stones

Our latest project is a town centre tenement building.  As soon as we are approached to survey one of these buildings, one of our fist concerns is surveying the rear of the property. These areas are difficult to access, maintenance is often neglected and they invariably in poor condition.

.

33 Academy Street Inverness survey inspection front elevation

.

The property is entirely enclosed by retail development, creating some challenging access issues.

We had planned to employ a drone to carry out the survey of the rear. This is not an entirely straightforward a solution as is sometimes made out. Drone surveys within the town centre require a flight plan to be lodged with air traffic control. They can only be carried out over properties where you have permission to fly. There are privacy issues, you need to fly close to the building and photograph all of its wall surfaces, including zooming in on windows to check their condition. The controllers also need a line-of-sight to the drone at all times. This means you need a good vantage point with plenty of room for launching and landing the drone.

.

Backland development at 33 Academy Street Inverness creating challenging access issues

.

On this occasion we were fortunate that Mcleod Roofing were carrying our repairs on a neighbouring property at 21 Academy Street. They kindly gave us permission to access their scaffolding, to inspect our property from the rear. We were also able to call in on our friends at HRI-Munro Architects across the road at number 62, who kindly allowed us take some photo's from their window.

Second piece of luck… It is clear from our inspection that stone indenting is going to be required to the decorative ashlar facade.

One of the stone reveals had fractured as a result of corrosion in a steel fixing. The stone was still secure, but one piece had broken off and was sitting on the window ledge. It was just big enough to allow testing and analysis. We can send this off for sampling and stone matching now, rather than having to wait for work to start and a scaffold to be erected.

.

Stone damage as a result of stone corrosion on the ashlar facade at 33 Academy Street Inverness

.

Stone analysis takes 4 weeks, then when a match is identified this, replacement stone needs to be ordered from the quarry which can take a further 12 weeks to arrive. Then it must be cut and shaped before placing on the building. That could be 16-18 weeks where the scaffold is up in a busy city centre and you are waiting for materials.

Removing this delay is a big win for the client.

.

MAAC studio are accredited conservation architects and principal designers working with traditional buildings throughout Scotland. 

If you need independent advice give us a call ?