Supporting a floor joist with a gallows bracket

[Smurfer]

Hi there

After some advice - I need to remove the trimmer joist as illustrated in the attached photo.

I think the best way to support the remaining joist is with some sort of gallows bracket, but there doesn't seem to be anything generic available... they're either too big (designed to support chimney breasts) or too small (designed to be shelf brackets).

Does anyone know of something in particular that would do the job?

It needs to be load bearing for domestic dwellings (1.5kN/m2 I believe), and it'll be anchored to an internal 100mm block wall.

Any advice appreciated.

 

[jks7492]

A short piece of angle? 100x100 RSA?

 

[noseall]

Hi there

After some advice - I need to remove the trimmer joist as illustrated in the attached photo.

I think the best way to support the remaining joist is with some sort of gallows bracket, but there doesn't seem to be anything generic available... they're either too big (designed to support chimney breasts) or too small (designed to be shelf brackets).

Does anyone know of something in particular that would do the job?

It needs to be load bearing for domestic dwellings (1.5kN/m2 I believe), and it'll be anchored to an internal 100mm block wall.

Any advice appreciated.


View attachment 313464

Is there no masonry behind the joist that you could fix into?

 

[^woody^]

Yeah, bolt it to the wall!

 

[Smurfer]

Is there no masonry behind the joist that you could fix into?

Yeah there is... it's an internal wall, are bolts going to support the weight well enough though? And presumably it would mean visible fixings on the other side of the wall? This would need to be signed off by building control too...

 

[^woody^]

Expansive bolt. It does not go through the whole wall. Allow for 75mm into the wall.

M10, one near the end at center line of joist, one 500mm in. You may need a timber packer between the joist and wall. A square washer would be nice.

 

[Smurfer]

Expansive bolt. It does not go through the whole wall. Allow for 75mm into the wall.

M10, one near the end at center line of joist, one 500mm in. You may need a timber packer between the joist and wall. A square washer would be nice.

Great advice, thankyou.

I actually have a bunch of those expansive bolts left over from the extension we've built too, used them for the rim joists, so sounds ideal... and I have some square washers somewhere.

I will give this some thought and will let you know the results

 

[noseall]

Great advice, thankyou.

You're welcome.

 

[^woody^]

You're welcome.

Teamwork makes the dream work.

 

[George_engineer]

Could you move the trimmer across? Bolting to the wall is easier although BC may want to see a load capacity design for it (although unlikely if it looks sturdy because it's not carrying much load)

 

[noseall]

Bolting to the wall is easier although BC may want to see a load capacity design for it

BC won't be interested.

 

[Smurfer]

BC will make a final visit at some point so they will likely see it. I've checked and there's only a small section of wall running along the joist, so I'm going to discuss with our contractor whether thats enough to bolt too.

Can't move the trimmer - the reason I need to get rid is to put a great big duct in between the joists to penetrate the outside

 

[Smurfer]

Update: Job done, I ended up putting 2 M16 bolts through the wall and the joist on the other side, anchored with resin, packed and fixed with square washers. Quite fiddly, I had to go in at an angle because lack of clearance to get the drill between joists. But it's rock solid, definitely isn't budging. Thanks for the advice