Lintel Advice - Steel/Concrete/Catnic?

2 May 2007
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United Kingdom
Hi All

I would like to open up an existing doorway into my extension, currently there is a 1350mm opening which i would like to extend to 2000mm. Lintel would be 2400mm in length.

There is a lintel of some description already in there but it is crumbling away and would like to replace BUT have no idea what to get

I have been on the catnic website and that is suggesting a CN81C which seems to have a SWL of 54kN but not sure if that is enough.

Its on the ground floor and will be holding up the external wall above. No cavity, 215mm thick wall 2 bricks thick. If i knew what the loading was this would be easier but i don't. Is there an easy way to work this out?

Is there a belt and braces solution ie a steel which would cover much more weight or should i just get the catnic?
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Just get the catnic. It will hold up any wall above it in a normal domestic situation.
A 203 x 203 x 46 steel beam would do the job and might be cheaper than a Catnic, though heavier to lift.
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No, just quicker to install; a Catnic solid wall lintel is more appropriate for an external wall rather than what will become an internal wall.
Or how about two 152 x 89s, one for each half of the wall thickness?

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