Insulation under the slab

Installing the insulation layer on which will be poured the foundation slab of the house. 

He had to convince the architect that the concrete slab should be ABOVE the insulation (and not the opposite, as with any "respectable house!"), so that the concrete slab acts as a heat accumulator when the sun shines (solar gain and thermal inertia are 2 of the principles of a passive house) and so can radiate back this stored heat into the house on cooler days. 

The formwork is in place, two more layers of insulation and the concrete rebar still to be installed.