Replacing garage roof joist

[nickjb]

One of the joists in my garage is getting beyond saving and starting to sag so it needs replacing. Its a pair of 3x2s on a 2.7m span so maybe a little under sized too. Ideally I'l replace it with something stiffer. The problem is the slot for the timber is only deep enough for the current sized joist. I can't enlarge it and I don't want to disturb the roof, which is likely to be asbestos.

Currently considering three options:
1. replace it like for like except pressure treated this time
2. replace it with one identical bit of timber then sister a shorter bit of 6x2 to that piece with coach bolts
3. thin down the ends of a bit of 6x2 so they will slot in the notches

Any thoughts on these or other solutions?

 

[Anstiss Ltd]

That to me looks like a small brick under the joist

Should be able to take that Out

 

[nickjb]

Should be able to take that Out

Its holding up next door's joist as well. They might not be so happy about it

 

[Anstiss Ltd]

Its holding up next door's joist as well. They might not be so happy about it

If your on good terms a simple prop would suffice it's a garage roof so not much loading

Re move brick fit your new joist put brick back just cut smaller to support then remove prop