Is ?my RSJ fitted correctly

[threesheds]

Hi,
Help and advice urgently needed. When I bought my Victorian house 15 years ago the kitchen had been knocked through into single storey outhouse. I have had to take down some ceiling and noticed that the main house wall (cavity wall) is sitting on one rsj set in the middle of the cavity. There are 2" thick pressed concrete slabs between the rsj and brick skins i.e the wall rests on the slab which in turn rests on the rsj. Is this acceptable or do I need an rsj under each skin? I've uploaded a diagram which hopefully shows the problem. The rsj is just on normal brick but I can easily change this for a concrete pad.
Many thanks
diagram at:
//media.diynot.com/201000_200769_57257_61612061_thumb.jpg

 

[pinenot]

In theory what you have is OK and has stood the test of time to validate that. However are we talking concrete paving slabs, or some form of reinforced concrete slab?

 

[pinenot]

In theory what you have is OK and has stood the test of time to validate that. However are we talking concrete paving slabs, or some form of reinforced concrete slab?

 

[threesheds]

Hi, thanks for the prompt response. They slabs look to me to be pressed concrete paving slabs, definitely not the cheap cast slabs, and there is no sign of any cracking in them. The reason I opened up teh ceiling is because some minor cracks in bricks in the support pillar have widened. I found what I expected the rsj in on the common brick not engineering brick or padstone. If the rsj is ok I'll prop the rsj and fit a padstone.
Thanks again.

 

[RonnyRaygun]

Hi,
Help and advice urgently needed. When I bought my Victorian house 15 years ago the kitchen had been knocked through into single storey outhouse. I have had to take down some ceiling and noticed that the main house wall (cavity wall) is sitting on one rsj set in the middle of the cavity. There are 2" thick pressed concrete slabs between the rsj and brick skins i.e the wall rests on the slab which in turn rests on the rsj. Is this acceptable or do I need an rsj under each skin? I've uploaded a diagram which hopefully shows the problem. The rsj is just on normal brick but I can easily change this for a concrete pad.
Many thanks

It's not what should be done. The usual solution is either a pair of beams, or a steel plate welded to the top flange.

Obviously at least part of each leaf of brickwork is above the steel beam and therefore the shear forces to the concrete slabs are greatly reduced.

If the slabs were taking the full shear load I think it's likely they would have failed long ago. As it is, they have lasted at least fifteen years with no problems so I don't see why you should start worrying now.

 

[tony1851]

In theory what you have is OK and has stood the test of time

In theory, it is definitely NOT ok to do it like that; a building control body would not accept it because of the shear force on the 2" thick flags.
However, as you pointed out, it has stood the test of time -so far. Goes to show that theory and practice often differ.

 

[^woody^]

As Tony and Ronny say, that is a crap way with normal slabs overhanging that much. And there is too much load on the outer flanges

Definitely not OK

But if it has been up for a very long time. It will do