ᐅ Proper Insulation for the Concrete Slab of a Garden Shed

Hello,
I want to plan a concrete slab foundation for a garden shed. The shed company recommends an insulated slab since the garden shed will also be insulated. At the same time, the company requires the slab to extend 10cm (4 inches) beyond the shed footprint on all sides. How can I insulate these overhangs to prevent thermal bridges? I plan to insulate from below with XPS boards and also on the sides.
Best regards,
andreas1806

Why do you insulate the garden shed, and is it really necessary?

If the garden shed is regularly heated and needs to stay frost-free, insulating the base plate (BP) could be beneficial.
If it is, as usual, unheated or only occasionally heated, insulating the base plate is unnecessary and would only increase heating costs slightly.

Hello,
Thanks for the information. No, it is not heated at all. However, electric garden tools or a pressure washer are also supposed to be stored there. The walls and roof will be insulated.
So, I assume I can skip the floor insulation then.
Best regards,
Andreas

Plug-in electrical appliances are not much affected by cold. For battery-powered devices, paints, and similar items, I would build an insulated cabinet and also provide heating for it. Insulation only makes sense if there is actual heating. Otherwise, it is only a matter of time until it becomes cold inside as well.

andreas1806 schrieb:

It should also be possible to store electric garden tools or a pressure washer there.

I also keep those in my "uninsulated" garden shed. I only bring the batteries inside and store them in a cupboard in the utility room. The rest, including the pressure washer, stays outside. Just make sure to drain it properly beforehand, and it works fine.