How much is an 8m long RSJ?

longwalks1

i know how long is a bit of string, but how much roughly would an RSJ be support a bedroom above it after taking out back wall of the house? Length approx 7.8m, and would have large (approx 6m wide) bi-fold doors under it?
Just a ballpark figure as i have no idea at all, are we talking hundreds, or thousands?

SailorSam

Shop around in builders merchants.

27col

Why would you not be asking this question of a steel supplier.
Then you would know exactly and not just approximately.

NICHOLAS_2

Probably less than 400 quid.

CKdesigner

Hi

It's not the cost of the steel to worry about, it's the cost of the total job that's important.

I can't remember what the 'rule of thumb' cost is but it's 1, 2 or 3 £'000 per meter. I've got a feeling it's £3,000 a meter for the complete job which means 8m would be £24K.

You also need to be careful when removing the whole back wall of your house, depending on the existing construction as you may need a steel box construction, which is 4 X steel beams making a box shape which will be more expensive still!

phill99

Before you get the price for the steel (which CKDesigner identifies), you need to engage a Structural Engineer. They will determine exactly what steel is required and its dimemsions.

CKdesigner

That's right Phil, the OP needs a structural engineer. But normally a decent builder will know one.

System

It's not quite as simple saying it's an 8m beam, they vary significantly in size/weight per m so it's not much use finding out the cost of a beam per se, you probably want to ask a builder for a rough costing before taking it much further...

Doozergirl

CKdesigner wrote: »

Hi

It's not the cost of the steel to worry about, it's the cost of the total job that's important.

I can't remember what the 'rule of thumb' cost is but it's 1, 2 or 3 £'000 per meter. I've got a feeling it's £3,000 a meter for the complete job which means 8m would be £24K.

You also need to be careful when removing the whole back wall of your house, depending on the existing construction as you may need a steel box construction, which is 4 X steel beams making a box shape which will be more expensive still!

Erm, it's really not! It's true that price per linear metre is affected by the size of the steel, but it's more likely to be around £40 per metre - so £320 plus VAT. Sometimes you need two. Very much an 'ish' but I had to comment - no way is it £24k!!

muckybutt

If you know the thicknesses the beam needs to be then have a look on here - not saying I recommend then just that they have an on line price calculator ...... certainly not £3k per meter as mentioned above :rotfl::rotfl::rotfl:
http://www.jgfabs.co.uk/beamsandcolumns/beamcalculator.php

martin1959

You would definitely need a structural engineer.


Even a RSJ at 8m may 'sag' slightly in the centre, which could easily interfere with the running of the bifold doors beneath,