Before you start with horror to summarize energy consumption for heating and worry that you made a mistake at the design stage heating system - stay calm: newly built homes tend to be more heat consumption, because the walls adopt to the new conditions.
Therefore, this first winter is not authoritative indicator of energy consumption. Worse, if you suspect that the heat escapes through the roof. - Even at first glance you can see that in places where the snow melts quickly, mistakes were made implementing the thermal insulation of the roof in the part used for an apartment. That's why on some roofs we notice the snow in perfect condition, and in other parts of translucent roof. You should, however, be aware that snow melting and exit may also be affected among others also properly constructed roof ventilation, soffit panel, roof shape, geographical location and the material from which made the roofing. During the first winter we see a need having such snow-hences.