Manchester: +44 (0)161 371 9524 London: +44 (0)20 3726 4825
Drone Survey – Remote Aerial Surveys & Inspections
Leigh Spinners Ltd – Leigh Spinner Mill Chimney Drone Survey
Crown Services attended the site on the 15th of August 2016 to carry out the visual inspection of the external fabric of a 65M chimney. This survey was undertaken by an unmanned aerial vehicle (drone). We used the drone aerial pictures to produce the inspection report along with any repair recommendations and costings.
This is a 65M brick chimney originally built between 1913 and 1923 to serve Leigh Spinners cotton mills. It was constructed from handmade curved bricks which formed the barrel of the chimney from base to the summit. Given the age of the build the chimney was in reasonable condition but there were a number of apparent issues that needed addressing to maintain the structure for the future. These issues were as follows:
There was a fairly high degree of vegetation growing from various parts of the chimney. The roots of plants infiltrated the brickwork causing the mortar joints to erode. We proposed carefully removing the plants to the root and treating with a masonry biocide which would help to reduce growth for a period of time.
It was visually apparent that patches of re-pointing which appeared to be concentrated around crack lines had been undertaken in recent years. However it was evident that there were large areas of brickwork with perished mortar which we recommended repairing. There were a small number of crack-lines to the brickwork but they appeared to be fairly superficial and a re-point would give back the strength it required.
At the summit of the chimney there was a large number of open cracks to the benching and along with re-pointing this we also recommended removing all loose crumbling flaunching and re-flaunch with a strong mortar.
Steel Retaining Bands:
There were 15 number of steel retaining bands which appeared structurally intact and in good order. However the cement flaunching to the bands was missing in many places, resulting in the vegetative growth as mentioned above but also the absence of mortar also leads to continuous seeping of water behind the bands which over time results in expansion and stress on the bolts and bands. Deflection of this water is achieved by cement flaunching. The bands themselves would also benefit from re-painting in a black bitumen paint.