Warm and cold waters did not create separate insulation schemes

Was submarine insulation different for boats intended for cold waters and warm waters?

Not significantly; operating range and the resulting size of the boat mattered more than a separate insulation scheme.

British submarines were not distinguished by major insulation changes for warm versus cold theatres. Size, endurance, and the operating area each boat had to reach mattered more. A short-range boat could exploit nearby bases, while distant patrols required more hull volume, fuel, and crew endurance. Geography and range therefore mattered more to these designs than separate warm- and cold-water insulation schemes.