On Tuesday, 25 September 2018 19:38:58 UTC+1, Chris J Dixon wrote:
Jeff Layman wrote:

Just fitted some insulation
(https://www.screwfix.com/p/hot-water-cylinder-jacket-18-x-80mm-x-1219mm/43483)
over a hot water cylinder which already had about 25mm of foam
insulation.

With existing tank insulation, can anybody do the maths to work
out how much difference the extra lagging will make?

I might well try to do the same, if there is any significant
benefit.

Chris

results depend heavily on what airgaps are left, and those are hard to control.


nt