PH performance

      

Over the last week the external temperatures in Dorset  have been ranging between -5 degrees C at night and +5 degrees C in the day time, sometimes reaching up to +8 degrees C on a sunny day.

We have noticed that the house maintains a constant temperature internally of around 20 degrees C in the rooms that face south (sometimes reaching up to 21/22 degrees C on a sunny day) and a constant 18 degrees c in the rooms facing north.

Something strange happens in the mornings when we wake up. I would expect the temperature to have dropped internally over night to correspond with the external drop in temperatures but it doesn’t.

Instead we have a warm and fresh, very comfortable feeling inside the house at 7am.

Why is this?

Is the slab heating up in the day time and acting as a heat sink releasing the heat at night?

Or is it the heat recovery unit balancing out the temperature whilst we are sleeping?

Or can the Warmcell insulation be acting as the heat sink?

Or is the timber frame detailing working hard at not allowing any cold bridging?

Or is it that we have never experienced living in an air tight timber framed house before? There is no moisture build up or cold spots on any of the internal external walls, & how are the ‘GORTEX’ vapour barrier and breather membranes performing?

Or is it a combination of all of the elements working hard together which is the Passivhaus principles?

Can someone please explain in plain English why we have a beautifully warm house ( without ANY  heating ) first thing in the morning…….