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Lintel size for load bearing wall opening

Postby idkkdi » Mon May 26, 2008 8:16 pm

I am planning on constructing an internal door way to my garage from the entrance hall of my house as I can only currently access it from the main garage door.
Can anyone confirm for me what size Lintel I require on what I believe to be a two skin wall one brick and one breeze block.
Also any info on cost of this lintel would be much appreciated.
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Postby rosebery » Tue May 27, 2008 11:48 pm

No, no and thrice no.

You need proper structural calculations to determine the specification of what you need.


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Postby Chris Langham » Sun Oct 19, 2008 4:32 pm

Rosebery is right. If you do not know how to do these you will have to consult an engineer
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Postby Dickie boy » Tue Oct 21, 2008 7:54 am

Also, be aware of building regs regarding doors from living space to a garage. As far as I'm aware you still have to install a fire door with intumescent strip, special hinges, door closer etc etc. It has got to protect you from the potential 12 gallons of fuel you have parked in there, not to mention all the cans of WD40 and de-icer you have knocking around !!!
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Postby eljaybee » Tue Oct 21, 2008 10:12 am

If you are only talking about a normal doorway opening (ie a 900mm wide opening) then structural calculations are a little over the top. You could simply install a box lintel to either leaf (you may even be able to get away with concrete lintels (pre-stressed reinforced).

I would ask at the builders merchants for what lintel they think and then clear it with building control before purchase and installation.

For a small opening of this size you shouldn't be asked for calculations unless you have something significantly out of the ordinary in the way of loads (eg a concrete first floor, or the wall is over 3 storeys high)
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Postby the specialist » Tue Jan 13, 2009 1:53 pm

eljaybe is right about the lintel and dickie boy is right about the fire door. Also if you've never done anything like this before I suggest you get someone into do it. Might be cheaper in the long run. I would also check with the building control about this alteration as it may come under building regs anyway.
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Postby eljaybee » Thu Jan 15, 2009 6:07 pm

Any structural opening in a loadbearing wall needs building regs approval.
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