[mark]

I am building over a flat roof garage which has a cavity wall except for the
front. Wall to be brick outer and block inner.
I need to put a cavity lintel over the front and this will be 3450mm long.
There is a choice of standard or heavy duty.

Which one do I need? The HD one is £200+ dearer than the standard. It's no
good asking the manufacturer as they just say have a structural eng. decide.
So can anyone tell me a typical application for each grade of lintel?

Thanks

mark

[Jim K[_3_]]

On Jun 13, 3:46 pm, "mark" wrote:
I am building over a flat roof garage which has a cavity wall except for the
front. Wall to be brick outer and block inner.
I need to put a cavity lintel over the front and this will be 3450mm long.
There is a choice of standard or heavy duty.

Which one do I need? The HD one is 200+ dearer than the standard. It's no
good asking the manufacturer as they just say have a structural eng. decide.
So can anyone tell me a typical application for each grade of lintel?

Thanks

mark

won;t your Building Inspector want a say in this?

Jim K

[mark]

"Jim K" wrote in message
...
On Jun 13, 3:46 pm, "mark" wrote:
I am building over a flat roof garage which has a cavity wall except for
the
front. Wall to be brick outer and block inner.
I need to put a cavity lintel over the front and this will be 3450mm
long.
There is a choice of standard or heavy duty.

Which one do I need? The HD one is 200+ dearer than the standard. It's
no
good asking the manufacturer as they just say have a structural eng.
decide.
So can anyone tell me a typical application for each grade of lintel?

Thanks

mark

won;t your Building Inspector want a say in this?


The BCO wants to see the lintel in place on her next visit.

mark

[Jim K[_3_]]

On Jun 13, 5:06 pm, "mark" wrote:
"Jim K" wrote in message

...



On Jun 13, 3:46 pm, "mark" wrote:
I am building over a flat roof garage which has a cavity wall except for
the
front. Wall to be brick outer and block inner.
I need to put a cavity lintel over the front and this will be 3450mm
long.
There is a choice of standard or heavy duty.

Which one do I need? The HD one is 200+ dearer than the standard. It's
no
good asking the manufacturer as they just say have a structural eng.
decide.
So can anyone tell me a typical application for each grade of lintel?

Thanks

mark

won;t your Building Inspector want a say in this?

The BCO wants to see the lintel in place on her next visit.

mark

best ask her what she expects to see then? otherwise you may end up
doing it twice....

Jim K

[Hugo Nebula]

[Default] On Mon, 13 Jun 2011 15:46:24 +0100, a certain chimpanzee,
"mark" , randomly hit the keyboard and
wrote:

So can anyone tell me a typical application for each grade of lintel?

It's to do with the loads on the lintel. The catalogues usually give a
safe working load (SWL). Wall loads are about 4.5kN/m^2, floors (in
dwellings) are about 2.0-2.25kN/m^2, roofs are between 1.5-2.5kN/m^2.
Multiply by the areas bearing onto the lintel, add a bit more to be on
the safe side, and you have you SWL.
--
Hugo Nebula
"If no-one on the internet wants a piece of this,
just how far from the pack have I strayed"?

[mark]

"harry" wrote in message
...
On Jun 13, 3:46 pm, "mark" wrote:
I am building over a flat roof garage which has a cavity wall except for
the
front. Wall to be brick outer and block inner.
I need to put a cavity lintel over the front and this will be 3450mm long.
There is a choice of standard or heavy duty.

Which one do I need? The HD one is £200+ dearer than the standard. It's no
good asking the manufacturer as they just say have a structural eng.
decide.
So can anyone tell me a typical application for each grade of lintel?

Thanks

mark

If you only have a couple of rows of blocks over it, the light one
will be sufficient. If it is the full triangle you will need the heavy
one.

Very important.
Before you start piling blocks on a long metal beam, support it in the
middle off the ground with a bit of timber (4"X2"). Remove when the
cement has set.
If you don't do this, the beam will sag.


It will have a bedroom above, brick and block wall with a conventional tiled
roof. Wall will have a large window.

I'll remember the tip. Or maybe let it set for a few days before loading.

mark

[mark]

"Hugo Nebula" abuse@localhost wrote in message
...
[Default] On Mon, 13 Jun 2011 15:46:24 +0100, a certain chimpanzee,
"mark" , randomly hit the keyboard and
wrote:

So can anyone tell me a typical application for each grade of lintel?

It's to do with the loads on the lintel. The catalogues usually give a
safe working load (SWL). Wall loads are about 4.5kN/m^2, floors (in
dwellings) are about 2.0-2.25kN/m^2, roofs are between 1.5-2.5kN/m^2.
Multiply by the areas bearing onto the lintel, add a bit more to be on
the safe side, and you have you SWL.
--

I think I understand what your saying but working out areas is the tricky
bit for me. I can do the maths but determining the areas of wall and roof
bearing down on to the lintel is where I come unstuck.
Thanks

mark

[harry]

On Jun 14, 1:47*pm, "mark" wrote:
"Hugo Nebula" abuse@localhost wrote in message

...

[Default] On Mon, 13 Jun 2011 15:46:24 +0100, a certain chimpanzee,
"mark" , randomly hit the keyboard and
wrote:

So can anyone tell me a typical application for each grade of lintel?

It's to do with the loads on the lintel. The catalogues usually give a
safe working load (SWL). Wall loads are about 4.5kN/m^2, floors (in
dwellings) are about 2.0-2.25kN/m^2, roofs are between 1.5-2.5kN/m^2.
Multiply by the areas bearing onto the lintel, add a bit more to be on
the safe side, and you have you SWL.
--

I think I understand what your saying but *working out areas is the tricky
bit for me. *I can do the maths but determining the areas of wall and roof
bearing down on to the lintel is where I come unstuck.
Thanks

mark

The lintel supports the triangle of masonary above it.
Just imagine the bit that would fall out if it wasn't there.
Work out the weight of that.

[Tim W[_3_]]

"mark" wrote in message
o.uk...

"Jim K" wrote in message
...
On Jun 13, 3:46 pm, "mark" wrote:

I am building over a flat roof garage ...
I need to put a cavity lintel over the front ...
There is a choice of standard or heavy duty.
Which one do I need? ...


won;t your Building Inspector want a say in this?


The BCO wants to see the lintel in place on her next visit.


If she is doing her job she will also want to have calculations to show that
your building is structurally sound. It is not her job to do those
calculations or to tell you what sort of lintel you need. It might be
acceptable for you to do the calculation yourself - I don't know - but
normally it is the job of a structural engineer. From the sound of it it
would be about ten minutes work for an engineer.

Tim W

[Roger Mills[_2_]]

On 14/06/2011 17:07, Tim W wrote:
wrote in message
o.uk...



The BCO wants to see the lintel in place on her next visit.


If she is doing her job she will also want to have calculations to show that
your building is structurally sound. It is not her job to do those
calculations or to tell you what sort of lintel you need. It might be
acceptable for you to do the calculation yourself - I don't know - but
normally it is the job of a structural engineer. From the sound of it it
would be about ten minutes work for an engineer.

Tim W

From my (limited) experience of BCOs, they seem to have an in-built
sense of what of reasonable, and will only ask for calculations if you
want to do something which they regard as 'marginal'.
--
Cheers,
Roger
____________
Please reply to Newsgroup. Whilst email address is valid, it is seldom
checked.

[Hugo Nebula]

[Default] On Tue, 14 Jun 2011 13:47:19 +0100, a certain chimpanzee,
"mark" , randomly hit the keyboard and
wrote:

I think I understand what your saying but working out areas is the tricky
bit for me. I can do the maths but determining the areas of wall and roof
bearing down on to the lintel is where I come unstuck.
Thanks

That's the simple bit. How tall is the wall? Multiply by the width of
the opening. Do the floor joists bear onto this lintel (directly or
indirectly)? If so, take half their length ('cos they're supported at
both ends), and multiply by the width of the opening. Do the rafters
and ceiling joists bear onto this lintel? ...
--
Hugo Nebula
"If no-one on the internet wants a piece of this,
just how far from the pack have I strayed"?

[mark]

"Hugo Nebula" abuse@localhost wrote in message
...
[Default] On Tue, 14 Jun 2011 13:47:19 +0100, a certain chimpanzee,
"mark" , randomly hit the keyboard and
wrote:

I think I understand what your saying but working out areas is the tricky
bit for me. I can do the maths but determining the areas of wall and roof
bearing down on to the lintel is where I come unstuck.
Thanks

That's the simple bit. How tall is the wall? Multiply by the width of
the opening. Do the floor joists bear onto this lintel (directly or
indirectly)? If so, take half their length ('cos they're supported at
both ends), and multiply by the width of the opening. Do the rafters
and ceiling joists bear onto this lintel? ...
--


The floor joists run parallel to lintel so I presume have no bearing on the
lintel.
The wall will be about 2.4m and the width 2m of which will be a window 2m
by 1.2m.
So about 2.4sq. m of brick/block wall directly above. I don't think it's
that easy because of triangulation which I'm aware of but my understanding
of which is a bit woolly. Is it an equilateral triangle with a base, in my
example of 2m wide?


Thanks for bearing with me.

mark