Insulating Steel I Beam on outside/inside skin Aluminium Windows above and Below avoid Cold Bridging

[mixermike]

I have steel beam on the outside skin. Thinking of Aluminium windows above and below.

I'm thinking if inner part of widow frame touches flange of beam then thermal bridging in the frame is lost.

Maybe encase beam with insulation?

So how best to insulate beam?

TIA

 

[JohnMo]

We have a metal frame around our window.  We added a frame to the outside in wood and the windows are mounted into that.  The steel frame was then wrapped in a combination of aerogel and 25mm PIR.

 

Have attached some images, zoom in to get a close look.

 

[mixermike]

23 hours ago, JohnMo said:

We have a metal frame around our window.  We added a frame to the outside in wood and the windows are mounted into that.  The steel frame was then wrapped in a combination of aerogel and 25mm PIR.

 

Have attached some images, zoom in to get a close look.

 

 Thanks for reply. How thick was the aerogel please?

[JohnMo]

34 minutes ago, mixermike said:

How thick was the aerogel please?

I used 10mm

[Jilly]

Same here

[Gus Potter]

On 28/04/2023 at 10:53, mixermike said:

I'm thinking if inner part of widow frame touches flange of beam then thermal bridging in the frame is lost.

Good question. Can you post a detail or make a rough sketch on what you expect to end up with? The beam looks like it is on the inner leaf? What is the wall makeup?

 

 

[Conor]

Too late now, but this is how my architect dealt with it. We had a 5m beam doing similar to yours, supporting bi-folds under and 5 fixed units above. He and the SE specced a 200mm square hallow section beam. To this there was a (12mm?) Plate that was welded to the underside that projected out to the exterior side. And on the top we had 5mm brackets made. They both prjected out slightly less than the depth of the framrs. This meant the main part of the beam was behind the bulk of the wall insulation. The window / door frames sat on/under the plates but sat out a bit. This means the plates could be behind the eventual spandrel panel.

 

Insulated the gap between the doors / window, and on the inside I wrapped the top of the box beam in aerogel. Seems to have worked really well.

[Dave Jones]

what is the cost of aerogel and where buy it out of interest ?

[mixermike]

20 hours ago, Gus Potter said:

Good question. Can you post a detail or make a rough sketch on what you expect to end up with? The beam looks like it is on the inner leaf? What is the wall makeup?

 

Thanks for reply.

The Beam is on the outer leaf, supported by dense block in the centre.

[mixermike]

Should Aluminium windows be fitted directly to steel beams or have wood of other material between?

[Gus Potter]

On 28/04/2023 at 12:40, JohnMo said:

Have attached some images, zoom in to get a close look.

Like have you have formed the posts supporting the canopy.. elegant.. accentuates the height and slenderness... I think.

[JohnMo]

1 hour ago, Gus Potter said:

Like have you have formed the posts supporting the canopy.. elegant.. accentuates the height and slenderness... I think.

The original design by architect and structural engineer had the framing of the windows and supporting the roof in wood, the posts were huge and ugly.

 

Challenged the design, and it came back in 200mm box section, so calculated what was needed and challenged again and ended up with this