Replace Timber beam with Flitch beam

Giggidy

We had a structural engineer check the stability of a chimney stack (chimney breasts removed from both floors below about 10 years ago) in the loft of a property we are hoping to buy. In his report, he recommended the following:

- Chimney Stack needs remedial work, has a big crack and the single timber with steel plate resting on top of it needs replacing
- Replace the Timber Beam by a flitch beam 2 No.50x200 C24 w/ 1No.12x200 S355 Steel Plate Bolted together w/ M12@375mm C/C resting on

Steel Spreader plate of 100x400x40mm THK for both ends.

He confirmed this would need to be approved by Building Control and they may require a survey is done first. 

We need to figure out how much this will set us back if we do the work once we own the property, the vendor is happy to do it but we are hoping to exchange soon and just take it off the offer price (there are other issues not just this)

Section62

Giggidy said:

We need to figure out how much this will set us back if we do the work once we own the property, the vendor is happy to do it but we are hoping to exchange soon and just take it off the offer price (there are other issues not just this)

You really need to get some suitably experienced builders to quote for the work, although this can be difficult where the work is speculative based on a property you'd like to buy, rather than a property you already own.

The current owners are more likely to be able to get builders to quote for the work, and it would probably be easier for making arrangements for the builders to visit.

The cost of work of this type varies quite widely depending on things like location and access. E.g. the size and shape of the loft can make a big difference to the complexity of the job. So an estimate based on the materials alone won't be a very reliable guide.

Have you also considered the possibility of removing the remainder of the chimney stack rather than replacing the support?  This isn't always feasible (e.g. on a listed building) but is usually an option worth considering.

Giggidy

Ideally we would have preferred for the current owner to sort this as he is a builder and said he could do it. But we are conscious of this taking weeks to sort. 

Removing the chimney stack altogether is another possibilty, hopefully we get on with the neighbours so it wont be an issue with it being a party wall

Mistral001

The structural engineer might be able to give you an estimate on how much this will cost you.  Many will provide this service along with providing any rstructural calculations that Building Control require.  They will charge a fee for this additional service of course.  I suspect that the beam itself will be relatively inexpensive compared to the costs the work to install it such as temporary propping of the chimney stack, removal of the old beam and making good.  You could try to get a builder to price the work for you, but check with the vendor to see if they will accept this.

Giggidy

The structural engineer was good enough to give us the calculations in his report and also said he will ask building control to give an estimate of costs of required work, but this may take 2 weeks to come through. The vendors already had a grumble about the electrician and builder that went in earlier, not sure he would be accept another visit. I sent the calculations to the builder who went before, hopefully he can give us a rough estimate.