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StructuralEng
StructuralEng, Consultant
Category: Structural Engineering
Satisfied Customers: 7386
Experience:  Structural Engineer
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Hi, It is proposed to create a rear extension for an existing

Customer Question

Hi, It is proposed to create a rear extension for an existing 2 story house. The rear extension first floor (FF) external walls don't line up with the proposed ground floor walls, therefore steel beams needed to support the FF walls. The question is: is it enough to build the FF masonry cavity walls directly on the steel beams or they need special fixings or connecters?
Submitted: 3 years ago.
Category: Structural Engineering
Expert:  StructuralEng replied 3 years ago.

StructuralEng :

Hello

StructuralEng :

How are you doing? I'll be happy to assist you with this.

StructuralEng :

Do you have any drawings or dimensioned sketches that you can share?

JACUSTOMER-y6mex3re- :

Full Size Image

JACUSTOMER-y6mex3re- :

hello, thanks for your reply

JACUSTOMER-y6mex3re- :

I'm just concerned about the lateral stability of the FF walls

StructuralEng : Thank you. I'm away from my computer right now, but I'll look at it as soon as I get back
StructuralEng :

You can build CMU directly on steel, but the steel needs to be sized for strength and L/600 deflection

StructuralEng :

The starter bars for the CMU should be A706 reinforcing steel and be welded to the steel beams.

StructuralEng :

The walls will also need to be braced by the roof and floor diaphragms.

StructuralEng :

If you could rate my answer, I would appreciate it. I'll be happy to answer additional questions on the topic.

JACUSTOMER-y6mex3re- :

Many thanks for your reply. What diameter for starter bars and what distance? Can we use light weight concrete blocks? Regards

StructuralEng :

The thickness grout and rebar size and spacing will need to be determined by someone who is being paid to design the structure.

StructuralEng :

It will depend on the loading, height, thickness, grouting, wind speed.

StructuralEng :

and the end restraint conditions.