How thick is the insulation in a hot water cylinder Comments Off on How thick is the insulation in a hot water cylinder 18 Jan 2016 Vote Up 0 Vote Down Answered Public Public Private Electric Water Cylinders Anonymous asked January 18, 2016 Hey How thick is the insulation in a hot water cylinder? 1 answer Vote Up 0 Vote Down Public ⋅ January 20, 2016 The insulation in a hot water cylinder is 50mm. #1 Please login or Register to Submit Answer