Does it make sense to have a base insulation with us?

Hello everyone,

I would like to insulate the base area of our detached house.

Our basement is not completely underground, but protrudes about 10-15 cm above the ground on the north side. On the sides (east/west) it is partially free-standing up to half a meter (sometimes more, sometimes less), and on the front side the exterior basement wall is completely uncovered in many places, so it is not embedded in the ground.

I have informed myself, but could not exactly find out how many centimeters of insulation make sense in the base area. Would 15-30 cm be sufficient? That would of course save me a lot of work, as essentially only the north side would need to be partly exposed. On the other sides I could probably work without problems. Should I use normal facade insulation for the other exposed sides? Perimeter insulation is usually only used when the exterior wall is in the soil, if I understand correctly.

Our basement is not used for living purposes. I can't imagine that a waterproofing was installed in the basement area at that time, yet I have not found a single wet or visibly damp spot in the basement.

Does it even make sense to insulate only the base area? I would like to do this because we renovated the house two years ago when we bought it and installed underfloor heating. We insulated the basement ceiling completely with PUR, as we did not have much space under the underfloor heating due to the ceiling height. To compensate for this, I would like to insulate the base area from the outside.

Thank you

Unfortunately, I was not quick enough with editing. On the north side, there are about 17cm where the basement sticks out of the ground. Otherwise, on the other sides at least 25cm.