Steels over bi-folds - detailing

[Moonshine]

i have two bi-folds one 3.6m and one 3m, due to a cock up in ordering i am now using steel beams over the openings, with beam sizes specified by the SE

 

Below is the rough detail i have drawn (there will need to be a cavity tray and weep holes above the opening), and i am scratching my head how to support the render and wet plaster over the areas of the beams, and also what to do about the area of the exposed beam on the outside just above the bi-folds.

 

Any 0ther comments on the detailings would be welcome (e.g. cold bridging

[George]

Plasterboard on the inside and cement board on the outside. 

 

To hide it, either just paint the steel black or some sort of wrap around power coated flashing. . 

 

Make sure the spec of the steel paint in the outer leaf is corrosion resistant (or galvanised).

[markc]

I would have the beam galvanised, even a very good paint spec will need maintenance

[nod]

I would use one steel over the bifolds with a hit and miss plate welded to the underside to catch the outer skin of block 

 

[Dave Jones]

for a normal 300mm wall, have a 290mm (to hide the joint) plate welded to the steel to sit the ourside brickwork on.

 

The SE should be speccing this anyway.

[Moonshine]

5 hours ago, nod said:

I would use one steel over the bifolds with a hit and miss plate welded to the underside to catch the outer skin of block 

 

 

Do you have a detail / diagram for this?

[nod]

17 minutes ago, Moonshine said:

 

Do you have a detail / diagram for this?