External double skin wall - Steel beam support 2

[SKD_BW]

Hi all,

I think this is a simple question but I can't find any guidance in the Eurocode or my structural designers guides.

A 203x203x60 UC beam is sufficient to support the load of a double skin external wall, however the width of the wall is approx. 250mm (allowing for a 50mm cavity). Is it best practise to support both skins fully, i.e. use either a wider beam or a 10mm thick 250mm wide plate to fully support both skins and then position the beam centrally between the outer edge of both brickwork skins?

I am concerned the 203mm UC will leave at least 25mm overhang (maybe more depending on the width of the cavity) on both the internal and external skin, which will be potentially unstable.

Is this the case for all external walls? For instance natural stone which could be 300mm+. I cant image upsizing the beam, hence I assumed a plate would be the simplest way to fully support the walls.

Thanks in advance for your help on this

Cheers

Adam

 

[HTURKAK]

[quote...... Is this the case for all external walls? For instance natural stone which could be 300mm+. I cant image upsizing the beam, hence I assumed a plate would be the simplest way to fully support the walls.][/quote]

No..This is not the general case.. the following sketch shows that the masonry wall supported by steel H beam , while the exterior decorative brick veneer is supported on angle..

Pls provide more info. to get better responds..

This web site shows a lot of applicable details

https://www.imiweb.org/conceptual-wall-section-brick-block-cavity-wall/

 

[BAretired]

A 25mm overhang for a 100mm brick veneer is normal architectural practice. More than 25mm would be excessive.

BA

 

[SKD_BW]

Cheers guys, I knew this community would have the answer straight away. Always ridiculously helpful - thanks!

@BAretired - Is that based on a standard I can quote for allowable over hang, or a rule of just a rule of thumb based on centre of gravity / load transfer?

@HTURKAK - that is very helpful, thanks.

 

[BAretired]

It is based on what I have seen in practice, and also based on common sense. Usually, in my experience, architects do not want to see steel flush with the face of brick, so they keep the steel back a little. One inch ensures that the kern of the brick is fully supported.

There may be a written rule somewhere, but if so, I don't know where to find it.

BA

 

[SKD_BW]

Thanks BA, that makes a lot of sense, cheers.