Structural Steel Fabrication - how wide to search?

[Fallingditch]

We're in NE Essex.

Our Structural Engineers have specified two 1.5 tonne steel trusses to support our gambrel roof.

Somewhat surprised to see that our local fabricator has quoted a figure which doesn't give us much change from £5k.

I have no idea of how much trusses cost - but have to say was somewhat surprised by that fugure (hey, what do I know).

Question is, should I be looking for a fabricator much further afield? (I remember reading about a steel framed extension in Islington which was fabricated in West Yorkshire and lorried down).

Tips, anyone?

 

[Onoff]

Try my fabricator, P & W Nash (Engineering) Services Ltd in Hoo near Rochester. Tel: 01634 250986 and ask for Stuart. 

Been using for 30 years at work and for home. They're first class. They also have an excellent relationship with Medway Galvanising so can supply in that finish depending on size etc. (It does add a fair bit to the cost). 

Tell Stuart Clive said to call.

http://www.pwnash.co.uk/

[Onoff]

Thinking about it if you mention my name it'll probably be £10K 

[PeterW]

How wide is that span..??

254 UC of that size is going to be close to £140 a metre, and at 6 metres to the tonne you're looking at probably close on to 2.5 tonnes per frame..?

have they provided any flange or joint information as those angles on the 90 X 90 columns are going to need to be plated and designed carefully. I'd look at 4 sections - the base, the side / roof legs in two halves and then the supporting 100 X 100 column. 

£5k isn't that unreasonable tbh

[Daedalus]

I think it's a good price. Assuming it covers erection?

For info steel normally costs £750/tonne off the mill (20% more for box sections).

And depending on the amount of fabrication I would be looking to pay anything £1500 - £ 3000 / tonne.

[Fallingditch]

Thanks that's really useful !  

The span is 8m wide.

" have they provided any flange or joint information ? " - no, but thanks for the tip I will now ask

" assuming it covers erection? " - no, craning extra (but we'll be using someone else for that)

We have been back to the Structural Engineer. He has now given more details on the spec and suggested that we can use a smaller UC (since we can accept a greater deflection). Price has now dropped significantly - more like £3.5k ...

So next steps are for me to get the revised spec, determine what the weight of it is going to be, and then I'll have a better idea of competitiveness ...

 

 

 

 

[PeterW]

So the reason the UC is so big is because he has put two uprights providing the support to the roof part way into the span. It may be worth checking if you can move those outward and angled to end on top of the supporting walls as then the lower UC is only taking the load from the centre (which will be less as you are putting the "arch" into compression)

Flange detail will be critical as the bolts will be in shear if it's done correctly but the number and type will need to be part of the spec !

[jamiehamy]

Revised price seems okay. We paid around £1k for a 5m length for our balustrade - weighed in at 265kgs iirc.