Custom footbed devices, methods of constructing the devices and kits for constructing custom footbeds are disclosed that may be particularly advantageous in the treatment of plantar ulcers. The devices offer the advantage of off-loading pressure from the plantar ulcers in a device that is easy to construct, reusable, lightweight, and custom-made to improve patient comfort. The footbeds are constructed using a curable substrate that is formed to the plantar surface of the foot except in the areas occupied by spacers designed to off-load wounds on the bottom of the foot.