Insulating steel uprights and beam.

[Dodgyrog]

Greatly appreciate the ongoing help from here.

As per below details we're soon to be installing steelwork consisting of 2 x outer I-Beam uprights (C1) then 2 inner 80mm square section windposts (WP1) which then all support a cross beam with welded plate (to support inner and outer leaves above windows and doors.)

Would like to insulate / protect from thermal bridging / condensation as much as possible so I'm maybe thinking something like aerogel 10mm insulation or similar? wrapped around the 80mm windposts - they are sat within the 100mm cavity. Any thoughts / better options out there?

Then how best to insulate the outer I-beam (B3) uprights that will have the inner face flush with the inner face of the inner leaf?

Finally how best to counter the thermal bridge created by the cross beam and plate which spans the complete cavity wall.?

TIA

 

[tony1851]

Stick 32.5mm PIR insulated plasterboard over the walls and around the RHS. The latter will probably need additional fire protection, eg by adding some Fireline board over the insulated plasterboard.

 

[Dodgyrog]

Stick 32.5mm PIR insulated plasterboard over the walls and around the RHS. The latter will probably need additional fire protection, eg by adding some Fireline board over the insulated plasterboard.

Thanks. Having recently used insulated plasterboard on my garage conversion I did think of this but I'm assuming you just mean only put it on the single wall where all the steel is? 3 of 4 walls are external of a 5m x 4m room and that means a lot of expensive insulated plasterboard otherwise.

If I only do the far wall one edge of the flange of the C1 uprights will just encroach where the side walls meets the end wall though (hopefully shown clear enough in the drg above) but maybe I can just install a thin strip of insulated plasterboard in the corners leaving me a slight step in the wall - which wouldn't be too unsightly.

Does that all sound feasible?

And if I do that would insulating the uprights themselves with a 10mm thick aerogel wrap then be overkill?

 

[jks7492]

Would it not be simpler to do away with the two SHS posts and just form the whole elevation as a single opening with the door framed out as part of the glazing?

 

[Dodgyrog]

Would it not be simpler to do away with the two SHS posts and just form the whole elevation as a single opening with the door framed out as part of the glazing?

Yes it would have been a lot simpler however I wanted a very specific look to the room with narrow rendered columns between the windows and the door so that it didn't look too "conservatory-like / fabricated" if that makes sense - as per the sketch. Wanted to maximise the window space, hence the columns being a lot less width than the minimum required width if it were just blocks, hence the steels.... which cost me, yes, but I do get hung up on detail