Do we need a structural engineer?

[Helen Vowls]

Just had a quote back from a firm (via our architect) to provide detailed design drawings (structural engineering, below ground and water surface drainage design and design management, whatever that is).  The quote is extortionate.  I’ve a feeling our timber frame company can do this so have asked them for a quote.  Do we actually need to be spending 20k+ on this?

[joe90]

I had no structural engineer input on my build, there must be something weird/different/complicated for an SE input to be required.

[nod]

10 minutes ago, Helen Vowls said:

Just had a quote back from a firm (via our architect) to provide detailed design drawings (structural engineering, below ground and water surface drainage design and design management, whatever that is).  The quote is extortionate.  I’ve a feeling our timber frame company can do this so have asked them for a quote.  Do we actually need to be spending 20k+ on this?

Your foundation design and any steel calcs  should be done by a SE Ours also added to The Block and beam and floor joists design ( done by others)

We were under 500 quid for everything 

[DevilDamo]

Timber frame companies will have their own in house engineers. But in instances where you will require any additional engineering, e.g. steel beams then that would need to be dealt with via an engineer.

 

TF companies wouldn’t normally design the new foundations or floors. Assuming the floors are not timber, then they would also need to be designed by an engineer.

 

TF companies would not get involved in any civil engineering including foul/surface water drainage so again, that would need to be designed by an engineer.

 

You haven’t provided much, if any information on what the project is, so it may be relative. How does the engineering fee compare to your architects’ fee?

[joe90]

5 minutes ago, DevilDamo said:

TF companies wouldn’t normally design the new foundations or floors. Assuming the floors are not timber, then they would also need to be designed by an engineer.

I think you will find @Jeremy Harris timber frame in house SE designed everything for his build including foundations (passive slab).

[SimonD]

1 hour ago, Helen Vowls said:

Just had a quote back from a firm (via our architect) to provide detailed design drawings (structural engineering, below ground and water surface drainage design and design management, whatever that is).  The quote is extortionate.  I’ve a feeling our timber frame company can do this so have asked them for a quote.  Do we actually need to be spending 20k+ on this?

Hello Helen,

 

I'm not suggesting what you've received is reasonable, but does the quote separate the distinct items of work? I suspect you've probably received a quote for much more than the structural design. Detailed design or construction drawings will typically cost a fair amount of money, whether by your architect or other technician. I'd also suspect that within the quote, the SE portion is fairly modest, unless you're building somethng very special and challenging indeed! However, it can and does depend on who's quoting for the SE portion of work. We had quotes ranging from about 1500 all the way to over 8500 for the structural design.

[dnb]

I agree with DevilDamo, the answers here would get more accurate with a bit more information about the project. I suspect that the £20k work package duplicates things you might already be paying for elsewhere. The obvious example would be the timber frame structual design - the timber frame supplier ought to have their own on the payroll. I also suspect that the design management element is the job of passing the information between the various SEs that will be working on the job. e.g the foundation designer needs to know about loads imposed by the building. I dealt with this aspect of the build myself, supported by my architect so that I didn't make too many mistakes. I did all the drainage designs myself and both building control and the warranty people seem happy with this. (I am a professional engineer, but nothing whatsoever to do with buildings). Unless you are building a proper grand design I can't see £20k worth of work there unless you want to be really hands off on your build. I don't believe I have spent anything like that on SE work with mine.