Christian McArdle wrote:

Would you still recommend hanging the front joists off a 'D' beam, or would
it be more economic to just span the lot and build the partition across the
joists? Note that an escape window will almost certainly be required that
will probably require floor space forward of the beam. I want at least some
light storage space in front of the beam, including a compartment in the
escape window "tunnel" to hold a rope ladder and other safety equipment.

Sounds a bit like what I did...

Not a stunning picture, but you may be able to see what is going on. The
dwarf wall replaces the function of the purlin to the front. The space
from the wall to the eves will become cupboard space.

http://www.internode.co.uk/temp/dwarf.jpg

You should be able to make out beam F at the back of the cupboard space

http://www.internode.co.uk/temp/beam-layout.gif

thisflys over the existing ceiling joists (which hold up a bonnet roof
over the bay window). The main floor joists are then hung below this
beam on long hangers. I presume similar could be done even if the floor
joists are SHS rather than timber.


--
Cheers,

John.

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