RSJ fitting not flush

[Clint101]

Hi I am having a rsj fitted thats
203 x 133 x 25 There are 2 of them one for inner and one for outer leaf they are 3.6m long.
The outer leaf rsj as been fitted but I'm unsure if it's correct I was expecting it to sit flush to the outer brick work but it sits proud about 25mm to 30mm see pic, am I wrong too assume it should fit flush..I thought that when the two rsj's are bolted together they would cover the cavity and both would sit flush to the wall.

 

[^woody^]

Lol. Are they going to step the plaster out?

Yeah, it should overhang the cavity, with the wall being bonded across the cavity, at least near the bearing, or a large single padstone crossing the cavity and taking the whole width of each beam.

 

[Clint101]

Thanks Woody,
The plasterboard on the extention side will be dot and dab so should hide the overhang, but I was abit dubious about the amount of overhang! Would this pass a building inspection?

 

[^woody^]

If you refer to the structural calculations, you should find that that is not in accordance with them.

Whether the inspector passes it or not, or even looks is one thing. Whether the bearing cracks and shears due to uneven loading is another.

Bottom line, you have shiite builders, or worse shiiter designer.

 

[Clint101]

Or both!! I have read that the web of the rsj should be central to the brick and this is not central.
Thanks Woody

 

[tony1851]

1. There's considerable eccentricity, which reduces the load-carrying capacity of the pier (though it might not be critical - depends on the actual load and other factors).

2. Is there no padstone, or are those engineering bricks?

3. For a 3.6m span carrying domestic loading, it should have been possible for the SE to put a little extra work in to be able to specify 203 x 102 beams, which would have been the same width as the bricks.

 

[Clint101]

Hi Tony
Yes they are solid engineering bricks, I was thinking that the width of the steel wouldn't of been such a problem if the builder had kept the web central to the brick and slightly overhang the cavity, yes I agree the specs on the plan says 133 the builder may of put it central if it were 102 it's about 20mm-25mm off of center as it is now.

 

[Clint101]

Sorry Tony about 15mm off center.

 

[Clint101]

I think this needs to be redone, the inner and outer leaf plus the cavity = 270mm the 2 RSJ,s when bolted tight together = 266mm
One of the RSJ,s has spacers, so padstone to cross the cavity at same width of the 2 RSJ,s..but I will need to find a padstone to fit, the SE asks for 400mm x 100 x 215 but that won't cross the cavity. So how does the builder do this, I really don't understand why the builder didn't pick this up, he's just doing what he wants

 

[tony1851]

See if you can get a short length of 9" x 4" pre-cast concrete lintel (sometimes you can pick up cracked ones cheap at the merchants) and cut to 270mm length with a disc cutter.
It will bridge the cavity and to an extent will help stabilize the two skins; bed it on 1:3 mortar.
You also wouldn't need to reposition the overhanging beam if it was to be too much effort.

 

[freddiemercurystwin]

Tony apart from the practicalities of overboarding the wall to achieve a flush wall, once loaded where is the beam gonna go? If the (crap) builder is happy to ensure the finish is flush then surely no action is necessary?

 

[tony1851]

Freddy, you are almost certainly correct. The eccentricity of the web from the centreline of the brick looks to be about 1/6. This will reduce the load-bearing capacity of the brick skin, probably by 25-30%. But that may not be of any consequence if the brickwork is in reasonable condition and the loading not too high.

I only suggested bridging the cavity as the OP seemed to be considering that?

 

[cdbe]

Have you asked your builder? It almost looks like the strongboy or something is stopping it moving over. Maybe he's gone to think about it over the weekend.

 

[Charlie George]

Have you asked your builder? It almost looks like the strongboy or something is stopping it moving over. Maybe he's gone to think about it over the weekend.

Could be just that, or left like that to make space for the other steel, to fit bolts, then push them together.

 

[Clint101]

Hi Guys thank you all so much for the comments, the builder as told me he didn't push it back because there was a concrete lintel in the way on the inner leaf he said when he gets the second steel in place he will push the outer leaf steel back to meet it, I doubt this was his intention from the start as he had already packed and mortered the steel in place! Its only when I complained that he told me the reason why he didn't.
All this could of been avoided if he had given it more thought and had more than 4 acrows.