T C Rowan runs an in-house steel design and detailing office at our Banbury workshop, turning your architect’s plans and your structural engineer’s calculations into accurate, buildable drawings before a single section is cut. We carry out the site survey, build the 3D model, and produce the general arrangement (GA) drawings, fabrication drawings and connection details that the workshop then works to. This is the front end of the same promise that runs through everything we do: one fabricator from drawing to final bolt. Because the people who detail your steel are the same people who fabricate and erect it, the drawings are made by hands that know exactly how the steel goes together on site, which is what keeps a job from arriving wrong and stalling.
What our drawing office produces
Our detailing covers the full set of drawings a fabricated steel package needs, from the first arrangement sketch to the shop drawings the cutters and welders work from.
- General arrangement (GA) drawings that set out the overall steel layout, member positions, levels and grid lines, so everyone on the job is reading from the same picture
- Fabrication and shop drawings for each member: cutting lengths, hole positions, cleats, end plates and weld preparation, drawn to the detail the workshop needs to make the steel right first time
- Connection details drawn to the structural engineer’s design, whether bolted or welded, with the right plates, cleats and bolt grades shown
- 3D models that let us check fit, clashes and access before fabrication, and that feed the 2D drawings rather than redrawing the steel twice
- Assembly and erection marking so each piece is identified, sequenced and easy to find when it arrives on site
Need the workshop side of this? See our steel fabrication and structural steelwork pages, which is where these drawings turn into finished steel.
From site survey to buildable drawing
Good detailing starts with real dimensions, not assumed ones. The same drawing office discipline runs every job:
- Site survey. We measure the real openings, levels and tie-in points on site rather than trusting figures off a plan, so the steel is detailed to the building that actually exists. This sits alongside our site surveys and project management service.
- 3D model and GA drawings. We build a 3D model from your architect’s plans and the engineer’s calculations, then produce GA drawings that set the steel out clearly for approval.
- Fabrication drawings and connection details. Once the arrangement is agreed, we detail every member and connection into shop drawings the workshop can cut and weld from.
- Approval and coordination. Drawings are issued for the engineer’s and architect’s sign-off, and any queries are resolved before steel is cut, not after it is delivered.
Catching a clash or a wrong dimension on a drawing costs minutes. Catching it on site, after the steel is fabricated and craned in, costs days and remedial work. Detailing properly at the front is the cheapest insurance on the whole job.
Working with your engineer and architect
It matters how this responsibility is split, so we are clear about it. Member sizes, load capacities and connection design for load-bearing steel come from the project structural engineer: that is the structural calculation, and it is their work. Our role is to take those calculations and your architect’s design intent and produce the GA and fabrication drawings that make the steel buildable. We are detailers and fabricators, not structural engineers, so we coordinate with your engineer rather than performing the structural calculations ourselves.
In practice that coordination is where in-house detailing earns its keep. We reconcile the architect’s layout with the engineer’s structural scheme, flag where the two need a decision, and feed practical fabrication and erection knowledge back into the drawings, such as how a connection will actually be welded or where access for a bolt-up is tight. The engineer signs off the structure; we make sure the drawn steel matches both their calculations and the realities of the workshop and site.
Why in-house detailing matters
Plenty of steel jobs are detailed by one firm, fabricated by another and erected by a third. Every handover is a place where information gets lost, a dimension gets transcribed wrong, or a query waits a week for an answer. Running design, detailing, fabrication and erection under one roof removes those gaps.
When our own drawing office details the steel, the workshop is never guessing at someone else’s intent, and the erection team is fitting steel that was drawn with the survey in front of us. Queries are settled in the same building. This is the front end of our design and build solutions, the single line of responsibility that carries a project from first survey through to the last bolt being torqued on site.
Standards and accuracy
T C Rowan is CE approved and works to BS EN 1090 execution standards, the recognised standard for structural steelwork in the UK and Europe. Our detailing supports that standard: members and connections are drawn to the engineer’s design and the agreed execution class, and material traceability is available on request so the steel can be traced back to source where your project or Building Control requires it.
For load-bearing and structural alterations, the engineer’s calculation governs the steel, and work such as removing a load-bearing wall or fitting an RSJ also needs Building Control sign-off. We detail to those calculations and that approval rather than guessing dimensions, and we coordinate with your engineer and Building Control so the fabricated steel matches what has been approved. If you have plans, calculations or just an idea of what you need, contact us for a free quote and we will tell you what we need to start detailing.
Frequently asked questions
Do you produce fabrication drawings and GA drawings in-house?
Yes. We have our own CAD drawing office in Banbury and produce general arrangement (GA) drawings, fabrication and shop drawings, and connection details in-house. Because the same firm details, fabricates and erects the steel, the drawings are made by people who know exactly how the steel will be cut, welded and bolted on site.
Do you do the structural design, or do you work to my engineer’s calculations?
We work to your structural engineer’s calculations. Member sizes, load capacities and connection design for load-bearing steel come from the project structural engineer, and our drawing office turns those calculations into accurate GA and fabrication drawings. We are detailers and fabricators, not structural engineers, so we coordinate with your engineer rather than performing the structural calculations ourselves.
Can you detail steelwork from my architect’s plans?
Yes. We can take your architect’s plans and the structural engineer’s calculations, carry out a site survey to confirm real dimensions, and produce the GA and fabrication drawings from there. Where the architectural intent and the structural detail need reconciling, our drawing office coordinates with both the architect and the engineer before fabrication starts.
Does doing the detailing in-house speed the job up?
It usually does. When the firm that details the steel is the firm that fabricates and erects it, there is no handover gap between drawing office and workshop, queries get resolved directly, and the steel is checked against the real site before it is cut. That single line of responsibility is what keeps remedial fabrication and on-site clashes to a minimum.