Removal of loading bearing wall

Noneforit999

Aliss08 said:

The report from the structural engineer has stated that the wall was in fact a load bearing wall and that his calculation indicates that the assumed beam size would not be suitable for the presumed loadings. However, he would advise that the ceiling in the kitchen is opened up to confirm joist spans and confirm the size of the beam installed.  

How did the SE do calculations if he doesn't know the beam size?

The builder must know the size of the RSJ they installed so were the calculations done from that?

GDB2222

Noneforit999 said:

Aliss08 said:

The report from the structural engineer has stated that the wall was in fact a load bearing wall and that his calculation indicates that the assumed beam size would not be suitable for the presumed loadings. However, he would advise that the ceiling in the kitchen is opened up to confirm joist spans and confirm the size of the beam installed.  

How did the SE do calculations if he doesn't know the beam size?

The builder must know the size of the RSJ they installed so were the calculations done from that?

I assume the SE can see that there simply isn’t space within the ceiling for a big enough steel. The height of the beam is what gives it strength.

This means that, when it is redone, there’s likely to be a boxed in steel sticking down through the kitchen ceiling.  One way to pretty that up is to lower the entire ceiling, which of course will be an expensive job.

Section62

Noneforit999 said:

Aliss08 said:

The report from the structural engineer has stated that the wall was in fact a load bearing wall and that his calculation indicates that the assumed beam size would not be suitable for the presumed loadings. However, he would advise that the ceiling in the kitchen is opened up to confirm joist spans and confirm the size of the beam installed.  

How did the SE do calculations if he doesn't know the beam size?

"Assumed"

I.e. if the supposed beam has been boxed in then measuring the boxing in and deducting a fair amount for PB+finishes will give approximate maximum dimensions the beam can be.  Given that steel universal beams and columns are rolled to standardised sizes, it is fair to take a guess at what the beam dimensions are at most, which would allow the SE to form a view that the beam may be undersized for the load.

They can't be certain though, because it may not be a steel beam, and it may not be a standard type.  It is possible the original builder got a SE to design a solution which is more compact than could be achieved using off-the-shelf universal sections.  (Although this is obviously less likely to be the case if the builder thought the wall wasn't loadbearing and BR weren't required)

The only way of knowing for sure is to uncover it, and find out exactly what is there.

Noneforit999 said:

The builder must know the size of the RSJ they installed so were the calculations done from that?

AIUI the original builder is not available to ask.  I'm not sure I'd believe what they say anyway.

Aliss08

The SE assumed as follows:

The beam downstand measures approximately 160mm deep x 100mm wide below the ceiling (including plaster and finishes). By deducting the likely thickness of plaster finishes it appears that the beam would be around 150mm deep and less than 100mm wide. We have therefore assumed a steel beam size of 152 x 89 x 16UB that, we presume, supports the floor above the dining room and kitchen only. Our calculation indicates that the assumed beam size would not be suitable for the presumed loadings. However, we would advise that the ceiling in the kitchen is opened up to confirm joist spans and confirm the size of the beam installed.

Section62

Aliss08 said:

The SE assumed as follows:

The beam downstand measures approximately 160mm deep x 100mm wide below the ceiling (including plaster and finishes). By deducting the likely thickness of plaster finishes it appears that the beam would be around 150mm deep and less than 100mm wide. We have therefore assumed a steel beam size of 152 x 89 x 16UB that, we presume, supports the floor above the dining room and kitchen only. Our calculation indicates that the assumed beam size would not be suitable for the presumed loadings. However, we would advise that the ceiling in the kitchen is opened up to confirm joist spans and confirm the size of the beam installed.

That makes sense. (as per my previous post)

If the downstand is only 100mm wide (finished) then that seriously limits the possible options for the beam design.  Had it been a bit wider (say 120mm or 150mm) then there would have been options for a deeper (taller) beam that might be adequate, although there may still be questions about the way in which it had been installed.

Aliss08

Just to update further.

The vendor does not agree with the SE’s report and maintains the wall wasn’t load bearing.  She states that as the work was done 12 years ago any problems would have come to light by now and it may have been that Buildings Regulations were not needed in 2011.  However she has been advised to submit a Regularisation form to the council.  It all sounds like a contradiction but I will see what happens next re the Regularisation.

robatwork

Aliss08 said:

Just to update further.

The vendor does not agree with the SE’s report and maintains the wall wasn’t load bearing.  She states that as the work was done 12 years ago any problems would have come to light by now and it may have been that Buildings Regulations were not needed in 2011.  However she has been advised to submit a Regularisation form to the council.  It all sounds like a contradiction but I will see what happens next re the Regularisation.

I did not have sex with that woman
Cigarettes do not damage the lungs
Your money is safe in this pension fund

Do you believe the vendor more than the SE? Let's see how this turns out...

sheramber

What is her reason for believing it was not a load bearing wall when she said she didn’t know anything about it? Is she relying on the builder saying it. 

Problems have come light as movement has been noted. Why was that if not from the removal of the wall? 

Aliss08

Obviously I believe the SE but I guess he could be wrong.  Sheramber the vendor did eventually find the estimate from the builder which stated that it wasn’t a load bearing wall and that a steel had been inserted but no calculations or anything.  He has long since retired.

Exactly what has caused the movement!  

silvercar

We are just about to start work on removing a couple of stud walls that we thought were not load bearing. Turns out that where they meet is actually supporting laterally another steel that was put in years ago and the junction where they meet was the original external corner of the house, so just knocking the stud walls out could have caused a section of the back wall of the house to fall down.