Lintel-RSJ Question

[carlsbergy]

I have just bought a house with a ground floor extension off the rear of the house. I intend to demolish the ground floor extension (as no proper foundations). Where the main house is opened through to the extension. I have removed the plaster and there are 2 x lengths of 3x2 supporting the upper brickwork. This is obviously unsafe as this is supporting the whole upper wall of the house. The width of the current opening is approximately 6 ft. I intend to brick up the opening which will then become the rear external wall of the house (as it was originally built). Question: what is the largest span of lintel I can use to cover the opening or do I need an RSJ? Thanks

 

[noseall]

In openings of 1.8m or less, a proprietary steel lintel will suffice. no calc's needed

 

[andywc]

hi

there are lots and lots of proprietary lintels on the market; the likes of IG, Catnic, Jones etc spring to mind. i guess there are even more 'patent' copies, perhaps like those available from builders merchants shelves; i believe that jewson and travis perkins have their own branded ones for example.

the ones directly available from the builders merchants are likely to be the commonly used/asked for ones, but they probably don't represent the longest spans that can be achieved with a proprietary lintel.

the spec for the lintel you need will depend on what it's supporting and over what span. if the spans are longer and / or the loading is high [especially if there are any concentrated loads] then you may need to use a steel beam or two.

if you post some sketches here i'm sure there are lots of people that could give you some move specific advice.

regards

andrew

--------------------------------------------------------------------------------
Andrew Cartlidge BEng(Hons) MIStructE CEng
Chartered Structural Engineer
http://www.beamcalcs.co.uk

 

[carlsbergy]

Many thanks to both of you for your advice

 

[Alastairreid]

The width of the current opening is approximately 6 ft. I intend to brick up the opening which will then become the rear external wall of the house (as it was originally built). Question: what is the largest span of lintel I can use to cover the opening or do I need an RSJ? Thanks

if you are bricking the opening back up, why do you need to put an rsj in?.
or have i read this wrong

 

[stuart45]

Sounds like a good question to me.

 

[Shytalkz]

...The width of the current opening is approximately 6 ft. I intend to brick up the opening which will then become the rear external wall of the house (as it was originally built). Question: what is the largest span of lintel I can use to cover the opening or do I need an RSJ?

Hey Andy, good job this was not a Part 3/CM question, eh?! And why haven't you done your CPD....!

 

[andywc]

i'm assuming that the opening is moving from its current position to further along the wall; hence the need for the longest lintel, rather than one to replace the existing opening width... otherwise you're completely right of course

CPD...the question should be 'why haven't i filed my CPD with IStructE'. year on year i do more training, mentoring and ongoing professional development than i could ever clarify or justify in their little boxes [about all i could ever fit in there would be a meaningless list], but this year i have filled it up for them. the IStructE are looking at resolving this well recognised issued to keep in line with other professions; presumably with view to making CPD mandatory rather than optional in the not too distant future; which i have always campaigned for. without question CPD should be mandatory and accordingly i've decided to join the line of micoscopic hand writers and filled in their small boxes. Shytalkz, this isn't the topic for this area!!

 

[Shytalkz]

Just thought I'd ask.

 

[carlsbergy]

Sorry, I omitted to mention on first post, once I knock the extension down, I will be putting a window and door in the existing back of the house and then bricking up openings, hence question about span of RSJ.