Reinforcing floor joists for stud wall

[RobertBM]

Following from my previous post about moving a non-load bearing wall and building another, I’ve come to the conclusion life would be easier if I replaced it with a stud wall.

Project is for a 3600x2520(L,H) stud wall constructed with 47x100 timber, soundproofed with soundKnauff Earthwool Acoustic Roll, and with 15mm GYPROC SoundBloc.

Although the new stud wall is a lot lighter that the current solid wall, it’s not going to be as close to the sleeper wall. The diagram above shows the new position of the stud wall in relation to the to sleeper walls, which are 23inches left and 18 inches right.

Being as I’m going to submit a Building Notice rather than full plans, I’ll probably start construction before the first inspection (due to my irregular work hours). Now my research shows I’m likely to be asked to strengthen the floor joists, which are 54x100 with a 400mm distance between them.


The questions I have in my head are:

1/ How is this reinforcing done ?

2/ Is it a matter of buying similar graded 54x100 timber and attaching it to the side of the current joists (see diagram below)?

3/ How far should the reinforced part of the joist overlay the sleeper walls?

4/ Should I reinforce every other joist which is under the new stud wall?

5/ How would I join the old joist and new timber, screws or are there special bolts?

If someone could answer those questions I’d be very happy

Thanks for reading,

Robert

 

[mcluma]

how much are the floor joist apart

actually there is not much weight in your new wall,

If you are concerned you could always double up the bottom sole joist of your new wall,

its just a stud wall with no load bearing duty - is it?

 

[tony1851]

my research shows I’m likely to be asked to strengthen the floor joists,

What research was that, then?

 

[RobertBM]

how much are the floor joist apart

actually there is not much weight in your new wall,

If you are concerned you could always double up the bottom sole joist of your new wall,

its just a stud wall with no load bearing duty - is it?

The floor joists 54x100 and 400mm apart. No, I’ve been told it’s not a load bearing wall and everything I’ve seen seems to confirm this. Is doubling up the sole an accepted method by building regs? Just that I’ve not read anywhere where someone has done this.

 

[RobertBM]

my research shows I’m likely to be asked to strengthen the floor joists,

What research was that, then?

This is what I read in various places on the internet where the building inspector has asked for the joists to be reinforced, even though the wall was a non-load bearing stud wall (and the fllor joists were thicker than mine). Given that it’s probably not going to be expensive to reinforce the joists, I’m willing to do it. I’m just not sure which way is seen as being done correctly. Hence my post.

 

[tony1851]

You would not need to reinforce the joists, regardless of what any inspector may say; the loads are very low and the joists you have will be perfectly adequate.
However, the method you show (sistering similar-sized joists against the existing), spanning from sleeper wall to sleeper wall would be fine

 

[mcluma]

The joists are adequate, no need to reinforce them, a single header and footer will be fine.

actually by putting in the footer you are already reinforcing the floor, as you will cross link them all

 

[RobertBM]

Sounds good to me. Many thanks for everyone who has posted a reply to my questions.