Can I improve the insulation of a paneled porch?

[1001things]

I've got a flat roof porch that was single glazed full height as originally built, a fixed pane at the lower half, followed by a horizontal wooden bar, followed by another pane. Quite a few years ago the lower pane was replaced by a wood panel. The window frame is 3.5cm thick on the inside, 2cm thick on the outside, and the panel that was inserted (from paint on the outside to paper on thie inside) looks to be the same thickness, so 5.5cm of wood (and maybe some insulation wool filler?) separating the inside from outside.

The porch is covered by a flat roof that extends over the garage so the distance between porch ceiling and outside is probably very small. And probably not insulated.

Is all of this likely to be a significant cause of heat loss in the house? I'm assuming yes, but would like some advice please.

I'm intending to get a replacement DG window. When this is done is there anything I could or should do to improve insulation? Maybe some sort of pre-insulated panel? Or replacing the panelled area with brickwork? The door (which is at right angles to the window) could be moved up to 25cm, so 25cm would be about the tickness of wall that could be built 'on the inside'. To this I would guess the porch could be extended 'out' at the base by 5cm or so, to give a max wall thickness of 30cm. I can't think of any way to increase the space available in the over-ceiling space in order to fit insulation there.

Anyway, i appreicate any advice.

 

[JohnD]

you have to treat a porch as bering outdoors, and use the front door of your house to cut it off from the inside space.

to insulate it effectively you need about 100mm in roof and walls, and dg windows. The window is presumably smaller than the roof and walls so is not the first thing to address.

It is not clear from your post what this porch is built of.

 

[^woody^]

Is all of this likely to be a significant cause of heat loss in the house?

No

There will be very little gain in insulating a porch, and veeeeeeery long payback times if you start messing about with the walls and roof purely to insulate them

 

[1001things]

thanks all. think i made a mistake in terminology on this one. the "porch" is actually the hall where it extends beyond the main rectangle of the house. so the "walls" and "roof" i'm wondering about insulating are the actual exterior walls and roof of the house there.

imagine the floor plan is a typical detached rectangle. the hallway splits the house in two through the long side and extends outside the rectangle as the "porch". it has two doors (one being the front door, the other being the door into the garage) plus the half glazed wall. the glass area in that wall is approx half of the entire wall.

btw, i measured the celing to base of roof height this evening and it is about 23.5cm. so presumably approx 23cm vertical inside, which presumably is more than enough for the 10cm mentioned by JohnD.