What happens next...?

[harry_angel]

We are attempting a loft conversion which, speaking freely, has divided opinion among both tradespeople and structural engineers.

 

Some have said: "you're going to need multiple cranked steels up there" (pushing the cost up to prohibitive levels), others have said "it's already stood for 100 years with a 350kg water tank up there forcing down, it'll be fine by doubling up all the joists, strengthening this, securing that etc".

 

Ultimately we've found a structural engineer who'll design it without floor steels but with flitch beams. His ltd company has been in business since 2012. Likewise, we have a well known building regs company willing to sign off on said drawings. Finally, obviously, we have our own buildings insurance.

 

With some of the sceptics' words ringing in my ears, I want to take this to the worst case scenario: we convert this loft, gradually it pushes out the eaves or something, causing damage to load bearing walls and, generally, The House.

 

Can anyone explain what happens next?

 

We see mahoosive cracks appearing in the walls or something bowing dramatically and then we....

 

- call the structural engineer and his insurance covers the repairs cost?

- call the building regs guy and his insurance covers it?

- call our own insurance, show them the hard evidence that we engaged professionals BEFORE undertaking these works, and they then cover it?

 

What are the pitfalls? Where are the booby traps? I mean, I badly want this loft space (it's going to be an amazing f/t study), but I'm not completely stupid, I don't want to wreck my house doing it...

 

Any thoughts most welcome.

[Jilly]

I'm having the same conundrum and hoping I never have to answer the question you are asking!  Its well known that some structural engineers over engineer design solutions to cover their backs (maybe they've been caught out before?) I'm converting a stable which the first SE advised underpinning all round (eyewatering cost). I even asked BC advice pre commencement. They said if we could get an engineer to calculate that we are not changing the loading it would pass, which it has, so this is the route I have gone down. Find an SE with plenty of relevant experience. I guess if it came to a claim there would be plenty of buck passing legal stuff which would be sorted out by your insurers. 

 

 

[harry_angel]

@Jilly yes, SEs over-engineering is an understatement! I get it, their primary driving factor is to avoid getting sued but still, c'mon....

 

Good luck with yours, I am just keen to know exactly how the buck-passing would play out, if it came to that...and also how acrimonious said buck-passing would be (ie would we have to lawyer up to get one of them to step up...)

[PeterW]

No buck passing really. 
 

in the event of a failure, then your insurers would look at whether you had BRegs approval for the work. Once that is determined then they would look at whether it was built to design, and if the design was at fault, and then they would persue the appropriate parties insurer. If it’s a failure of a component that has been correctly designed and installed then the insurers will just pay up. 

[joe90]

+1 wot @PeterW said, I find SE,s over engineer everything so I would be happy as long as it is built to that spec, building regs approval and adequate house insurance. Water tight case (IMO).

[PeterW]

Also worth noting that different SE’s have different methods. I use one who used to design a lot of chemical engineering structures and he is well versed in having removable components for access. That means he knows the correct layout and calculation of bolt patterns and will design steels for ease of installation. 
 

Fast forward to them being installed and the BCO that comes out wants them site welded as “he doesn’t think bolts are enough”.. queue a series of questions about his technical knowledge and his insurance coverage or liability (none as LABC have no liability) and he reluctantly agreed to pass it as the SE said it was ok. In that case it is still signed off but at liability of the SE. 

 

There is a local SE to me that does a lot of timber structure designs but he lived in Canada for about 10 years and they rarely use steel. He had some real problems with BCOs not accepting some of his calculations as they were used to using standard steel sizings and couldn’t comprehend that a bit of wood was as good as a lump of steel.... 

[Ferdinand]

1 hour ago, harry_angel said:

 

 

Can anyone explain what happens next?

 

 

 

?

 

[joe90]

10 minutes ago, PeterW said:

Also worth noting that different SE’s have different methods.

when I lived in shropshire a neighbour, who was an SE, designed his cottage using oak beams but the BI would not sign it off saying he needed steels, it went to a tribunal of some sort and the “judge” found the SE was more qualified than the BI and overruled him ???