Hi We are about to erect a scaffold around a stack of diameter 4.5metre. The height of the stack is 60 metre and the scaffold is to be erected up to this height. We have already started the erection of scaffold to a height of 30 meter. The dimension of the scaffold is 7.5 meter X 7.5 Metre. I would like to know whether at this dimension it would be safe to erect the scaffold to a 60 metre height. Please send your comments and if possible send me a design calculation for the scaffold to my mail id. rrajasekarhse@gmail.com Rajasekar

This scaffold certainly needs designing - even if it was a basic independent, TG20 and the old BS5973 only catered for scaffolds up to 50m high. If you're stuck for a scaffold design engineer, let me know and I can point you in the right direction. As a (very) basic rule of thumb, if the scaffold was freestanding, the height to base ratio should be around 3 to 1, so the scaffold would have to be 20m x 20m at the base. This could be reduced by other means - extra bracing, kentledge, etc. or if support can be gained from the stack itself. However, only an engineer can provide the necessary design drawing and calculations for this.