Should I pay an invoice from Structural Engineer for substandard work?

Marania

I was considering taking out a load-bearing wall separating my kitchen and dining room to create an open-plan space.  I phoned an Architects company to do a survey and they sent a Structural Engineer. 
When the person came I explained to them what I wanted and told them that I can make holes in the ceiling anywhere they need so they can have a thorough look and get the right steel beam to support the floor above. The Engineer asked me to make two holes in the ceiling which I did. After the survey, the person left and got back to me a few days later with the suggested design of two supporting steel beams. It did look ok to me, after all, they are the professionals so they proceeded with the structural calculations. I received them soon after and gave them to a recommended construction company. Their manager examined them, gave me a quote and asked if he should go ahead and order the steel beams. My gut feeling made me take a ladder and look through the holes I had made in the ceiling for the engineer. I put my phone through the hole and took a picture. When I looked at it I realised the span of the floor joists is completely opposite to what the engineer had put on the plan. What is more, there was already a steel beam in the ceiling, which made the drawings and calculations utterly useless.
 Had I gone ahead with those structural calculations and drawings I would have bought the two steel beams, the builder would have started the demolition works and I would have incurred a significant financial loss. I contacted the Structural Engineer and told them about their mistake but they haven't cancelled the invoice. Should I pay it or dispute it?

dreamypuma

What was the structural engineers response when you queried their recommendations?

Have you put your findings and concerns in writing? If not I would do this asap, and request their formal response in writing.

JHW1942

As advised above, write to them to set out what you've found and ask for their response.

You caught their error in time and haven't suffered a consequential loss, so that has no bearing on any monies owed.  

Marania

Thank you for your responses, I'll write to them again and ask to cancel the invoice. 

pinkshoes

Marania said:

Thank you for your responses, I'll write to them again and ask to cancel the invoice. 

I'm not sure you actually have the right to cancel, but you can certainly ask them to rectify their mistake and issue the correct plans!

gettingtheresometime

You say there's already a steel beam there but is it sufficient enough to do the job that you'll want it to do , once the load bearing wall is removed?.

Marania

gettingtheresometime said:

You say there's already a steel beam there but is it sufficient enough to do the job that you'll want it to do , once the load bearing wall is removed?.

The existing steel beam that is already in the ceiling (which the engineer didn't spot) is actually resting on the very load-bearing wall that I wanted to be removed. So the drawings and calculations of the engineer are all worthless.

Marania

pinkshoes said:

Marania said:

Thank you for your responses, I'll write to them again and ask to cancel the invoice. 

I'm not sure you actually have the right to cancel, but you can certainly ask them to rectify their mistake and issue the correct plans!

Had the engineer identified that there's already an existing beam in the ceiling, resting on the very wall I wanted to be removed I would not have proceeded with any structural calculations and I would have paid them for their visit. They, however, came, did their survey and did not identify the existing steel beam, they did not identify the correct direction of the floor joist and produced their calculations base on the wrong data. Had I proceeded with those calculations, the builder would have begun demolition work and would have had to stop at some point and that would have left me thousands of pounds out of pocket to make good what was demolished.

ComicGeek

Marania said:

pinkshoes said:

Marania said:

Thank you for your responses, I'll write to them again and ask to cancel the invoice. 

I'm not sure you actually have the right to cancel, but you can certainly ask them to rectify their mistake and issue the correct plans!

Had I proceeded with those calculations, the builder would have begun demolition work and would have had to stop at some point and that would have left me thousands of pounds out of pocket to make good what was demolished.

Not really, as the builder would have realised that the information was wrong as soon as the ceiling was taken down. There would have been some moaning about rubbish structural engineers, a quick phone call to discuss and resolve, and then life would have carried on. The new steel location would need to be site measured so couldn't be ordered until exposed, so no real losses incurred yet. 

However, important to absolutely doublecheck that what is there currently is sufficient, and you need a structural engineer to do this. The existing steel shouldn't be 'resting' on the wall, it needs to be self supporting with the wall below built up to it. I would be getting the engineer to come out again and inspect fully - I would make it clear that I wouldn't be paying for their previous survey and calculations, but let's start again and get it right.

If the existing wall isn't load bearing anymore, then you may have saved the costs of building control sign-off depending on what else you're doing.