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  #1   Report Post  
Andrew Barnes
 
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Default Beam Calculation

Hi There

As a strict DIYer i would like to calculate the size of beam required to
support a wall, when I make a 2m wide opening in a wall.

I am an engineer, but have been working in science for years, so don't know
where to start!

Can anyone offer any help or advice?

Thanks

Andrew


  #2   Report Post  
Stefek Zaba
 
Posts: n/a
Default

Andrew Barnes wrote:

Hi There

As a strict DIYer i would like to calculate the size of beam required to
support a wall, when I make a 2m wide opening in a wall.

I am an engineer, but have been working in science for years, so don't know
where to start!

Can anyone offer any help or advice?

Aye - Tony Bryer will be along in a while, but until he's here I'll plug
his allegedly excellent SuperBeam program, which you can get a
fully-functional print-disabled version of at

http://www.sda.co.uk/sbwdemo.htm

More design factors than you'd ever considered ;-) For such a relatively
tiny gap, you'll prolly find a simple off-the-shelf part at your local
Jewsons which is more than adequate. But that's just me handwaving...

  #3   Report Post  
IMM
 
Posts: n/a
Default


"Andrew Barnes" wrote in message
...
Hi There

As a strict DIYer i would like to calculate the size of beam required to
support a wall, when I make a 2m wide opening in a wall.

I am an engineer, but have been working in science for years, so don't

know
where to start!

Can anyone offer any help or advice?

Thanks

Andrew


Use a wooden "I" beam, not over engineered steel.

See:
http://www.masonite-beams.se

They will do the calcs for you.


  #4   Report Post  
Tony Bryer
 
Posts: n/a
Default

In article , Imm wrote:
Use a wooden "I" beam, not over engineered steel.

See:
http://www.masonite-beams.se


I quite agree on not using an over-engineered steel. But, by
definition, the correctly chosen section in any particular location
will not be over-engineered. I suspect that the OP will find that a
127 x 76 UB, 13kg/m is quite adequate but would advise him to get
the calcs to confirm this from someone who is qualified (small 'q')
to do so. As to using a wooden I-beam I could not find any span/load
tables on the above site but generally would not advocate supporting
masonry walls off timber, even though this was done in past times.

--
Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk
Free SEDBUK boiler database browser http://www.sda.co.uk/qsedbuk.htm


  #5   Report Post  
IMM
 
Posts: n/a
Default


"Tony Bryer" wrote in message
...
In article , Imm wrote:
Use a wooden "I" beam, not over engineered steel.

See:
http://www.masonite-beams.se


I quite agree on not using an over-engineered steel. But, by
definition, the correctly chosen section in any particular location
will not be over-engineered. I suspect that the OP will find that a
127 x 76 UB, 13kg/m is quite adequate but would advise him to get
the calcs to confirm this from someone who is qualified (small 'q')
to do so. As to using a wooden I-beam I could not find any span/load
tables on the above site but generally would not advocate supporting
masonry walls off timber, even though this was done in past times.


In the USA it is common to support brick walls with TJIs.




  #6   Report Post  
Tony Bryer
 
Posts: n/a
Default

In article , Imm wrote:
In the USA it is common to support brick walls with TJIs.


It's a fundamentally unsound idea. TJI beams have got next to no
lateral stability. This is not a problem with floors because the
diaphragm effect of the floor deck keeps them straight and upright.
If you put a beam under a wall where does the lateral support come
from? In addition the OP wants to take out a wall at ground floor
level and support the wall over with a beam taking ? 2-3 tons which
means that at either end there will be an upward reaction of one ton
or more on the bottom flange of the beam. There's no way any
checking engineer would let you do this on a ply web beam without
designed stiffeners.

If you can direct us to some span/load tables we might just see what
would be needed.

--
Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk
Free SEDBUK boiler database browser http://www.sda.co.uk/qsedbuk.htm


  #7   Report Post  
dg
 
Posts: n/a
Default

"Tony Bryer" wrote in message
...
In article , Imm wrote:
In the USA it is common to support brick walls with TJIs.


It's a fundamentally unsound idea. TJI beams have got next to no
lateral stability. This is not a problem with floors because the
diaphragm effect of the floor deck keeps them straight and upright.
If you put a beam under a wall where does the lateral support come
from? In addition the OP wants to take out a wall at ground floor
level and support the wall over with a beam taking ? 2-3 tons which
means that at either end there will be an upward reaction of one ton
or more on the bottom flange of the beam. There's no way any
checking engineer would let you do this on a ply web beam without
designed stiffeners.

If you can direct us to some span/load tables we might just see what
would be needed.

--
Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk
Free SEDBUK boiler database browser http://www.sda.co.uk/qsedbuk.htm



Although I agree that use of such a beam is a bad idea, it is interesting to
note the many houses built up to the mid 60's with first floor walls built
off a single or doubled timber joist.

Walls built off timber from new would settle naturally, but its a different
matter when retrospectively fitting a timber support in situations like
this.

dg

  #8   Report Post  
G&M
 
Posts: n/a
Default


"Tony Bryer" wrote in message
...

but generally would not advocate supporting
masonry walls off timber, even though this was done in past times.



Why on earth not ? In most old houses it is the stone lintels that fail,
not the wooden ones. The only time wooden ones fail is when there is an
unfixed source of damp causing decay. Our house has bits up to 400 years
old and a good mixture of oak, stone and modern lintels in the extension,
and I bet I know which bits will still be intact in another couple of
hundred years.



  #9   Report Post  
dg
 
Posts: n/a
Default

"G&M" wrote in message
...

"Tony Bryer" wrote in message
...

but generally would not advocate supporting
masonry walls off timber, even though this was done in past times.



Why on earth not ? In most old houses it is the stone lintels that fail,
not the wooden ones. The only time wooden ones fail is when there is an
unfixed source of damp causing decay. Our house has bits up to 400 years
old and a good mixture of oak, stone and modern lintels in the extension,
and I bet I know which bits will still be intact in another couple of
hundred years.




Well the main problem is progressive and seasonal movement, which may not
only play havoc with the decorations of a modern house, but may not be
suitable to other materials in the structure which don't cope to well with
such movement.

dg

  #10   Report Post  
G&M
 
Posts: n/a
Default


"dg" wrote in message
.. .
"G&M" wrote in message
...

"Tony Bryer" wrote in message
...

but generally would not advocate supporting
masonry walls off timber, even though this was done in past times.



Why on earth not ? In most old houses it is the stone lintels that

fail,
not the wooden ones. The only time wooden ones fail is when there is an
unfixed source of damp causing decay. Our house has bits up to 400

years
old and a good mixture of oak, stone and modern lintels in the

extension,
and I bet I know which bits will still be intact in another couple of
hundred years.




Well the main problem is progressive and seasonal movement, which may not
only play havoc with the decorations of a modern house, but may not be
suitable to other materials in the structure which don't cope to well with
such movement.


Use lime mortar (as Grand Designs did tonight) and such problems go away.







  #11   Report Post  
John Rumm
 
Posts: n/a
Default

Andrew Barnes wrote:

As a strict DIYer i would like to calculate the size of beam required to
support a wall, when I make a 2m wide opening in a wall.


Knowing what load is going to be supported by said beam would be one of
your prerequisites.

Is this a load bearing wall? What is is made out of?



--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/
  #12   Report Post  
Andrew Barnes
 
Posts: n/a
Default



Knowing what load is going to be supported by said beam would be one of
your prerequisites.

Is this a load bearing wall? What is is made out of?


It is a solid brick wall (single thickness) supporting a similarly sized
wall above. The joists upstairs run parallel to it, as do those in the loft,
so I assume there is no load from the floors on it?

The wall is between my kitchen and dining room, I wish to make a
kitchen-diner.

The calcs need to satisfy a building officer!

Thanks

Andrew



  #13   Report Post  
Dave Plowman (News)
 
Posts: n/a
Default

In article ,
Andrew Barnes wrote:
It is a solid brick wall (single thickness) supporting a similarly sized
wall above. The joists upstairs run parallel to it, as do those in the
loft, so I assume there is no load from the floors on it?


The wall is between my kitchen and dining room, I wish to make a
kitchen-diner.


I'm willing to bet anything you can buy of that length (2m) will be fine.

The calcs need to satisfy a building officer!


But my bet won't. ;-)

--
*Real women don't have hot flashes, they have power surges.

Dave Plowman London SW
To e-mail, change noise into sound.
  #14   Report Post  
The Natural Philosopher
 
Posts: n/a
Default

Andrew Barnes wrote:

Knowing what load is going to be supported by said beam would be one of
your prerequisites.

Is this a load bearing wall? What is is made out of?



It is a solid brick wall (single thickness) supporting a similarly sized
wall above. The joists upstairs run parallel to it, as do those in the loft,
so I assume there is no load from the floors on it?

The wall is between my kitchen and dining room, I wish to make a
kitchen-diner.

The calcs need to satisfy a building officer!


In that case just get a structural engineering firm to do the calcs.
They will be believed by the BCO and have professional indemnity
insurance if it falls down.


Thanks

Andrew




  #15   Report Post  
Hugo Nebula
 
Posts: n/a
Default

On Wed, 15 Sep 2004 08:10:59 +0100, a particular chimpanzee named
"Andrew Barnes" randomly hit the
keyboard and produced:

The calcs need to satisfy a building officer!


Are you sure? Has he asked you for calculations, or just to let him
know what beam you intend to put in? IME, for a 2m opening, if you
were to specify a reasonably-sized beam (i.e., a 178 x 102 UB) then
it's unlikely that the BCO wouldn't accept this without calculations.

If necessary you could try a box lintel from Catnic, who I understand
will provide calculations for you.
--
Hugo Nebula
'What you have to ask yourself is, "if no-one on the internet wants
a piece of this, just how far from the pack have you strayed?"'


  #16   Report Post  
G&M
 
Posts: n/a
Default


"Hugo Nebula" abuse@localhost wrote in message
...
On Wed, 15 Sep 2004 08:10:59 +0100, a particular chimpanzee named
"Andrew Barnes" randomly hit the
keyboard and produced:

The calcs need to satisfy a building officer!


Are you sure? Has he asked you for calculations, or just to let him
know what beam you intend to put in? IME, for a 2m opening, if you
were to specify a reasonably-sized beam (i.e., a 178 x 102 UB) then
it's unlikely that the BCO wouldn't accept this without calculations.


Mine wanted calculations for a 80 cm opening over a doorway (2 standard
100*65 lintels)



  #17   Report Post  
Hugo Nebula
 
Posts: n/a
Default

On Fri, 24 Sep 2004 21:24:59 +0100, a particular chimpanzee named
"G&M" randomly hit the keyboard and
produced:

Mine wanted calculations for a 80 cm opening over a doorway (2 standard
100*65 lintels)


With point loads on them or less than three courses of masonry over
them, perhaps? Pre-stressed lintels require the composite effect of
the masonry over them to work satisfactorily. Perhaps asking for
calcs was a way of proving to someone who argues every point that they
won't work.

Or maybe you've just ****ed him off something rotten.
--
Hugo Nebula
'What you have to ask yourself is, "if no-one on the internet wants
a piece of this, just how far from the pack have you strayed?"'
  #18   Report Post  
dg
 
Posts: n/a
Default

"Andrew Barnes" wrote in message
...
Hi There

As a strict DIYer i would like to calculate the size of beam required to
support a wall, when I make a 2m wide opening in a wall.

I am an engineer, but have been working in science for years, so don't

know
where to start!

Can anyone offer any help or advice?

Thanks

Andrew



There are various examples to be found by a quick Google. Try BS 5950

But a good general building reference book, which has some basic worked
examples is The Building Construction Handbook, by Chudley and Greeno. Its
about £15 and well worth it

First you need to know the load that a beam of a given section can carry,
then work out the load that it will be supporting. Once you have the
formula, steel section tables are available from Corus, and another Google
on ' weights of building materials ' will get you the info to work out the
loading.

I don't know if the Superbeam program already mentioned is available as a
trial. But its the lazy option if you want it !

dg

  #19   Report Post  
IMM
 
Posts: n/a
Default


"dg" wrote in message
k...
"Andrew Barnes" wrote in message
...
Hi There

As a strict DIYer i would like to calculate the size of beam required to
support a wall, when I make a 2m wide opening in a wall.

I am an engineer, but have been working in science for years, so don't

know
where to start!

Can anyone offer any help or advice?

Thanks

Andrew



There are various examples to be found by a quick Google. Try BS 5950

But a good general building reference book, which has some basic worked
examples is The Building Construction Handbook, by Chudley and Greeno. Its
about £15 and well worth it

First you need to know the load that a beam of a given section can carry,
then work out the load that it will be supporting. Once you have the
formula, steel section tables are available from Corus, and another Google
on ' weights of building materials ' will get you the info to work out the
loading.


Steel? get real a TJI "I" beam will do for most instances.


  #20   Report Post  
Clive Summerfield
 
Posts: n/a
Default


"IMM" wrote in message
...

"dg" wrote in message
k...
"Andrew Barnes" wrote in message
...
Hi There

As a strict DIYer i would like to calculate the size of beam required

to
support a wall, when I make a 2m wide opening in a wall.

I am an engineer, but have been working in science for years, so don't

know
where to start!

Can anyone offer any help or advice?

Thanks

Andrew



There are various examples to be found by a quick Google. Try BS 5950

But a good general building reference book, which has some basic worked
examples is The Building Construction Handbook, by Chudley and Greeno.

Its
about £15 and well worth it

First you need to know the load that a beam of a given section can

carry,
then work out the load that it will be supporting. Once you have the
formula, steel section tables are available from Corus, and another

Google
on ' weights of building materials ' will get you the info to work out

the
loading.


Steel? get real a TJI "I" beam will do for most instances.


In the real world, price is always a consideration. Not sure what the price
of a 2m Trus Joist is, but a 14' 6"x4" steel beam cost me £35 about 2 years
ago.

Cheers
Clive




  #21   Report Post  
Des Higgins
 
Posts: n/a
Default


"Andrew Barnes" wrote in message
...
Hi There

As a strict DIYer i would like to calculate the size of beam required to
support a wall, when I make a 2m wide opening in a wall.

I am an engineer, but have been working in science for years, so don't

know
where to start!

Can anyone offer any help or advice?


This is just an anecdote relating to the above and is not meant to be smart:
I heard of an engineer whose first job was for the Irish Telephone company
in the early 1980s and his first assignment was to put a generator up on a
"beam". He got the weight of the generator and calculated load factors and
stuff
by looking up some big tables for different materials and doing some
calculations. Then he went to put the beam up. When he tried to find beams
of certains sizes and/or materials, his choice was severely limited.
In the end he used the biggest beam he could find.
I suspect you will end up doing something similar (or biggest beam that is
cheap and manageable)?

Des


Thanks

Andrew





  #22   Report Post  
The Natural Philosopher
 
Posts: n/a
Default

Des Higgins wrote:

"Andrew Barnes" wrote in message
...

Hi There

As a strict DIYer i would like to calculate the size of beam required to
support a wall, when I make a 2m wide opening in a wall.

I am an engineer, but have been working in science for years, so don't


know

where to start!

Can anyone offer any help or advice?



This is just an anecdote relating to the above and is not meant to be smart:
I heard of an engineer whose first job was for the Irish Telephone company
in the early 1980s and his first assignment was to put a generator up on a
"beam". He got the weight of the generator and calculated load factors and
stuff
by looking up some big tables for different materials and doing some
calculations. Then he went to put the beam up. When he tried to find beams
of certains sizes and/or materials, his choice was severely limited.
In the end he used the biggest beam he could find.
I suspect you will end up doing something similar (or biggest beam that is
cheap and manageable)?


Indeed.

In the end, 'big enough' is all it has to be.
'Too big' is when it won't fit...

The steel cost is not huge.

Just get an I beam that comfortably fits in, and use that.
I'd say a 6x3 I beam is more than man enough.



Des



Thanks

Andrew







  #23   Report Post  
Dave Plowman (News)
 
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Default

In article ,
Des Higgins wrote:
I suspect you will end up doing something similar (or biggest beam that
is cheap and manageable)?


I removed a stud but load bearing wall between kitchen and scullery. About
4 metres wide. BO was involved because of other works, and wanted
calculations. Which I got. Smallest RSJ was fine, not surprisingly.

--
*You are validating my inherent mistrust of strangers

Dave Plowman London SW
To e-mail, change noise into sound.
  #24   Report Post  
John Rumm
 
Posts: n/a
Default

Des Higgins wrote:


I suspect you will end up doing something similar (or biggest beam that is
cheap and manageable)?


To be fair, some of the steel fabricators are very flexible these days.
You can order pretty much exactly what you need.

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/
  #25   Report Post  
dg
 
Posts: n/a
Default

"John Rumm" wrote in message
...
Des Higgins wrote:


I suspect you will end up doing something similar (or biggest beam that

is
cheap and manageable)?


To be fair, some of the steel fabricators are very flexible these days.
You can order pretty much exactly what you need.

--
Cheers,

John.


Our local steel suppliers will do the calcs, and select a suitable beam for
you if you ask nicely

dg



  #26   Report Post  
 
Posts: n/a
Default

I had some advice from the group recently on getting a beam. The
structural engineers I contacted wouldn't get out of bed for less than
=A3250!

I downloaded the SDA product. which worked a treat to calculate the
beam I needed.

Tim


dg wrote:
"Tony Bryer" wrote in message
...
In article , Imm wrote:
In the USA it is common to support brick walls with TJIs.


It's a fundamentally unsound idea. TJI beams have got next to no
lateral stability. This is not a problem with floors because the
diaphragm effect of the floor deck keeps them straight and upright.
If you put a beam under a wall where does the lateral support come
from? In addition the OP wants to take out a wall at ground floor
level and support the wall over with a beam taking ? 2-3 tons which
means that at either end there will be an upward reaction of one

ton
or more on the bottom flange of the beam. There's no way any
checking engineer would let you do this on a ply web beam without
designed stiffeners.

If you can direct us to some span/load tables we might just see

what
would be needed.

--
Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk
Free SEDBUK boiler database browser

http://www.sda.co.uk/qsedbuk.htm



Although I agree that use of such a beam is a bad idea, it is

interesting to
note the many houses built up to the mid 60's with first floor walls

built
off a single or doubled timber joist.

Walls built off timber from new would settle naturally, but its a

different
matter when retrospectively fitting a timber support in situations

like
this.
=20
dg


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