use of load bearing wall to rest joists

[teracir]

I am currently carrying our refurbishment of my house and have been tripping down the ceilings. I have planning permission to convert my loft into storage space but the problem I have is that the existing joists on 1st floor are 4 by2 and hence not strong enough to carry loads.

I am intending to install 7 by 2 but the wall between the rooms in partition wall. Can this be used to rest the joists on?

At the moment, the joists are bolted together in the middle of the room and the only thing supporting them in that partition wall.

from wall plate to wall plate, the distance is about 7.5 to 8m, can you get joists this long?

Any advice would be greatly appreciated.

 

[Deluks]

A partition wall can still be load bearing, whether your's is or not is anyone's guess. My guess is yes if flying ends of 4x2 are bolted together over it. But even if I'm right, the wall may only have been designed to support what's existing at the moment. Adding extra joists/floor/loads could overload it.

I'm intrigued by your opening statement.
I have planning permission to convert my loft into storage space

Storage space does not require planning permission, in fact most proper loft conversions don't require planning permission.

Who has given you permission and what exactly is it they permitted you to do?

 

[teracir]

origionlly I was ment to build a proper stair case upt to the lost and use itas an office space but this had to be rules out due to height of the celing (about 6ft). so i will be putting in loft ladder and using it as storage space.

Coming back to origional question, the current spacing between timbers in the partition are at 400 centres, if i replace these with a 300 centre stud wall that would provide extra strength. would this be sufficient?

 

[big-all]

i would suggest even though it cant be used for accomodation you do it in accordance to building regs then you have a part conversion that maybe at a later date can be upgraded

you need to go from the ground up to work out what the loadings can be at roof level

 

[teracir]

what are your recommendations?

 

[big-all]

you cannot increase the load by any great amount on the partion wall untill you know if its up to the job and any transferred load can be accomodated by the floor /wall and ground floor wall/beam as appropriate