newbuild - insulation issues; cavity exposed etc etc. pointers?

[wifigeek]

Hi All,

I live in a new timber framed house which is freezing cold. I had the hallway opened up by NHBC for further inspection and have since came across something that I dont think is right. looking for a builder in here to give further advice.

house type is a bellway rosedale.

Half way up the front hallway I have a hole cut where the front porch timber box meets the external brickwork on the main part of the house. there is a steel beam holding up the outside wall cavity but the wall cavity is open behind it? I can 'look up' to the roof space. is this normal?

some context -

loft hatch where hallway / leading from front door meets internal door for living area

a better picture of where this is exactly inside


just behind the steel beam shown above (where the insulation isnt) I can see right up the inside of the wall cavity to the roof. nothing there.


and the thermal images that show a problem -

other side of same area -

suggestions are more than welcome as NHBC are trying to fob me off with some insulation there is one hell of a draught coming from those areas as you might expect.

 

[wifigeek]

sorry having issues with the forum.

 

[John D v2.0]

So basically your insulation needs to be a continuous envelope around the warm area, and your air barrier needs to be touching the insulation o the warm side to prevent air blowing through the insulation or past it, and prevent condensation in cold voids
With that in mind, you indeed have a gap which needs filing with insulation, but it would need to be against the surrounding insulation, and that steel beam needs to be either inside or outside (as steel is not in any way insulation)
If the insulation is wool type, there is the need for a vcl on the warm side or the whole void needs packing as far as the plasterboard to prevent air movement.