What is happening with the Chimney at Aizlewood's Mill?
29th August 2017
What’s happening with the chimney at Aizlewood’s Mill?
The scaffolding on the chimney here at Aizlewood’s Mill has been up for quite some time now with nothing much going on, but work will be starting again soon on the major refurbishment required.
Over the past few years our chimney maintenance contractors, Rafferty Chimneys have been working on the outside repointing various areas and checking on the supporting bands. This year we commissioned them to take a detailed look on the inside which has brought up some interesting results.
The inside of the chimney was not actually scheduled for an inspection for another 20 years but the appearance of a number of loose bricks in the inspection hatch gave us cause for concern so we asked Raffertys to take the lid off and abseil down the inside. During this inspection they found a small number of loose bricks near the top which had been worked loose by vegetation like Buddleia anchoring itself to the side wall. They also found a wide band of deteriorating bricks at about the half-way point.
Further investigation uncovered the cause of this deterioration to be the high level of condensation in that area from the central heating boilers using the chimney as their flue. As the gases rise from the boilers in the winter they reach their dewpoint around half-way up and this makes the bricks in that area damp. If we were to keep the boilers working permanently this would not be a problem but as they are on and off during the day, and also only for about half the year this is causing the bricks to become wet and then dry and wet again.
The solution is to enter the chimney again and clear away all the loose and damaged bricks, install a mesh liner and then spray a special concrete coating up the full height which will make it completely water resistant.
The work is made harder by the chimney actually being very small inside. I was unaware until the engineers told me that the inside of the chimney is only 1 metre wide inside, from top to bottom. The chimney wall at the bottom is 5 bricks deep, pointing from outside to in, and then 2 bricks deep at the top. There is then a skin of transverse bricks on the outside to make it look like the rest of the building.
Quite a few of the Reception staff have had chance to ride in the crane basket to the top of the chimney on the outside to view the works from close up, but I have been offered the rare opportunity to go down the inside with one of the engineers to take a look there. It’s going to be tight squeeze and if I can get an internet connection I will try and master Facebook Live so you can all join me in the dark! Take a look at drone footage of our chimney!
http://www.aizlewoodsmill.co.uk/history - https://m.youtube.com/watch?v=GMxLP6BSIug&feature=youtu.be
