Drawings required?

[Jml]

Managed to get a structural engineer recommendation. On phoning him he says we need architect drawing for him to work off so he doesnt also need to do them and therfore we pay for them twice.  We did the drawings for the planning permission, for our extension, in what way do these architect drawings differ or add to these? Is this something we could do ourselves?

[curlewhouse]

Ours used the full architects drawings which are used to build from.

Edited October 23, 2017 by curlewhouse

[Lesgrandepotato]

There are in my experience normally two sets of drawings - the basic drawings for Planning.  Then if you are going for a full Building regs application (as opposed to a notice) and I would recommend you do. Then you'll need a subsequent set of drawings detailing how the building will be constructed. These are the drawings that the SE will then work from. 

 

You'll want the full BR drawings to get prices from builders anyway - otherwise it really is in the elements of guesswork. 

 

BigSpud

[MikeSharp01]

It is just detail, sizes and fixed points, if you did the planning drawings in CAD that may be all he needs but try to get everything close to perfect measurements / scale so there are no surprises. Our architect let the SE have a set of base drawings the SE did his stuff and sent his work back to the architect (and me) to be dropped back into his drawings to check everything fitted. The SE was using REVITT (3D) and the Architect used Archicad (3D). Not everything was right first time around but after a couple of iterations it looks like it will all work. If it is simple column / post stuff with roof stress / racking calcs it should be straight forward but checking is important in case the SE specifies a beam right through your favorite window because it was not on the drawing.

[Jml]

Many thanks for the responses.

 

1 hour ago, Lesgrandepotato said:

Then if you are going for a full Building regs application (as opposed to a notice) and I would recommend you do. 

 

We have to go for full building regulations as building over a sewer, but seems wise to do so anyway so no nasty suprises from building control.

 

1 hour ago, Lesgrandepotato said:

Then you'll need a subsequent set of drawings detailing how the building will be constructed. 

 

The net seems full of generic detailed construction drawings, sections etc. and I am  concerned we will just be paying for regurgitating these.

 

1 hour ago, MikeSharp01 said:

It is just detail, sizes and fixed points, if you did the planning drawings in CAD that may be all he needs but try to get everything close to perfect measurements / scale so there are no surprises.

 

I spent many long hours trying to get the as is measurements exact.  It took me a while to be  able to ignore 5mm differences when working in mm on CAD, having once spent hours trying to find out where the difference was in a room.  So the bungalow as is, am fairly confident would be sufficient for most purposes.  

 

Not so sure about the extension part as will depend on build up of floors, walls etc. for thicknesses, which is partly cost driven and may vary when it comes to the build.  Also if the structutal engineer suggests too complex beam work we may change the building layout and simplify.

 Did you get the drawings in 3d, I have been working with 2d  only?

[MikeSharp01]

58 minutes ago, Jml said:

Did you get the drawings in 3d, I have been working with 2d  only?

Yes but it has been a bit of a pain as manipulating them is tough, I have converted all the main drawings into 2D for the build but keep the 3D for reference. The interoperability standards for drawings are a complete pain, I was so frustrated by a 1mm difference between the Architect and the SE - which came down to decimal places rounding error, so once you have it in a form you can manipulate I would stick with that. On the extension you can let the SE build on your drawings their concern won't be the details that you a3re concerned about they will just do the loadings and, as you say, beam work. Just brief them to keep it simple and give you some lee way on lengths of columns if the floor build up might change. One thing that caught us, and the architect, out and required a reworking was the bases of columns extending beyond the walls in which the columns were built.

 

[Jeremy Harris]

My experience with 3D drawings is that the interoperability between different CAD packages can be pretty dire.  Much as the ancient .dxf format has it's limitations, at least I was always able to import and export emailed or downloaded files into my (also ancient) copy of AutoCad.  The only issue I can recall, and it was a pretty minor one, is that the Ordnance Survey files for the base map were out by a factor of 1000.  I never did find out quite what the problem was, but my guess is that whatever software they use to create the .dxf file has a scaling error, and sets the units to mm rather than metres in the .dxf header.

[Jml]

 

31 minutes ago, MikeSharp01 said:

Yes but it has been a bit of a pain as manipulating them is tough, I have converted all the main drawings into 2D for the build but keep the 3D for reference. The interoperability standards for drawings are a complete pain, I was so frustrated by a 1mm difference between the Architect and the SE - which came down to decimal places rounding error, so once you have it in a form you can manipulate I would stick with that. On the extension you can let the SE build on your drawings their concern won't be the details that you a3re concerned about they will just do the loadings and, as you say, beam work. Just brief them to keep it simple and give you some lee way on lengths of columns if the floor build up might change. One thing that caught us, and the architect, out and required a reworking was the bases of columns extending beyond the walls in which the columns were built.

 

 

Thanks for response, think will stick to 2-d, can mentally convert most things to 3d,  apart from stairs which I always seem to have problems with.

 

Good advice re: length of columns and keeping simple which is what we are aiming for.  We are hoping to minimise columns as most of work only infill ground floor extension and vaulted ceiling in place of current flat roof.

 

As your not that far away from us can I be cheeky and ask would you recommend your SE?

[MikeSharp01]

3 hours ago, Jml said:

As your not that far away from us can I be cheeky and ask would you recommend your SE?

Yes will PM you with his details, he is based in Mid Kent.