which lintel or not

[hardtail]

hi guys im going to rebuild the outfaces of our extension and fit a 1500 wide window ,above the window will be 4 courses of brick before it meets the flat room and at the minute there is no lintal present which should i fit or is it nessasary also i will be replacing the upvc door with one 900 wide (external dimensions) also 4 courses above same again none present at the minute hense the reason i wish to rebuilt the walls as the brick work would have been better if a blind man had done it .many thanks guys

 

[Richard C]

Firstly; be aware that what you’re proposing is controlled building work (walls, Lintels, windows & doors) & you need to make a building notice submission. Probably overkill for a flat roof but by far the easiest to fit, Catnick lintels; LABC will want to inspect them.

Secondly; the wall you’re taking out & replacing will almost certainly mean you falling foul of the “changing more than 24% of a thermal element rule”, Building Regs. Part L1B, which effectively requires you to bring the extension up to current insulation standards.

Talk to your LABC before you do anything, let them know what you propose & make a good excuse for doing it & they will probably let you get away with just re-building the wall your taking out to current standards! You will in all probability be asked to produce a compliance certificate for the work when you come to sell.

 

[PrenticeBoyofDerry]

As the load is not great from above, you should get away with 2 number 150mmx100mm section at a length that 300mm over the mason opening.
So if the opening is 1500mm the lintels must be 1800mm, so there is 150mm overhang on to the walls.
It al has to be building regulation compliant, and they could ask for calculations to be done by a structural engineer.

 

[noseall]

If you are proposing to re-build the outer skin only then either use a (proprietary pressed steel catnic or similar) timber frame lintel or a single wall angle lintel.