Frequently asked
Steel structure questions, answered
Plans, foundations, specification, cost and lead time — the questions we get asked every week, answered properly rather than deflected to a contact form.
Plans & approvals
Do I need approved building plans for a steel structure?
Yes. All permanent structures in South Africa require approved building plans before construction commences, and that includes sheds, workshops, hangars and carports. Requirements and interpretations vary between municipalities, so confirm with yours before you commit to a programme — approval time is often the longest lead item on the whole job.
Do you supply an engineer's certificate?
Yes, on request. Every structure we make is designed by a civil engineer, and we supply the engineer's drawing and certificate for your building plan submission. Your insurer and, on a commercial site, your occupancy certificate will both want it.
Who arranges the plan submission?
That is normally the client or their draughtsperson or architect, because the submission covers the whole site — position, coverage, boundaries, services — not just the structure. What we provide is the structural engineering that goes into it.
Foundations & site
What foundations does a portal frame need?
Isolated concrete bases under each column, sized to the loads that column carries and to what your soil can bear. Because a portal frame concentrates its load into a small number of points rather than spreading it along a wall, the bases are the critical item — and their size depends on the soil, which is why a soil assessment is worth having on anything substantial.
Are foundation bolts included?
Yes. All fasteners are supplied with the structure, including the foundation bolts. Getting those bolts cast in the right positions is the single most common cause of delay on erection day, so we supply the setting-out and it is worth checking twice before the concrete goes down.
Do I need a concrete floor?
Not necessarily. The structure stands on its column bases, so the floor is a separate decision. Plenty of implement sheds and covered yards work perfectly well on compacted gravel. If you do want a slab, cast it after erection or leave the base positions out and fill them afterwards.
How level does the site need to be?
Reasonably, but a slope is not a problem — it is a design input. We have built mini factory units with each bay stepped in height to follow a sloping site, which avoided cutting the platform flat. Tell us the fall across the footprint at enquiry stage.
Design & specification
What is a portal frame, and how does it differ from a truss?
A portal frame is a rigid frame — column and rafter joined into one continuous member with a stiff connection at the knee, so the whole frame acts together to resist load. A truss sits on top of columns as a separate element, carrying load through a triangulated web. For clear-span buildings the portal frame is usually lighter, quicker to erect and cheaper, because the frame does the bracing work that a truss building needs separate structure for. Trusses still win where you need great depth for services, or on very long spans with light loading.
What is IBR sheeting?
IBR — inverted box rib — is a trapezoidal roof and wall sheeting profile, the South African standard for industrial and agricultural roofing. Galvanised IBR is what we supply as standard, at a 10° roof pitch. Chromadek is the colour-coated option where appearance matters.
What is the standard roof pitch?
10 degrees. That is a deliberate choice for IBR sheeting — enough fall to drain and to keep the laps working, without the extra steel and wind exposure a steeper roof brings.
Can you build to my architect's or engineer's design?
Yes, and a good deal of our work is exactly that. We have fabricated a mine monorail to a supplied design, an architect-designed house near Irene, a pergola to an architect's specification and Corten-clad architectural steelwork. Send the drawings and we will quote to them.
How wide can you go?
Standard designs clear-span to 30m. Beyond that we usually carry the width on an internal row of columns — our 40m wide structure works that way — because a single clear span past 30m needs disproportionately more steel. If the floor genuinely cannot take a column, say so and we will quote the clear span.
Cost & lead time
What does a steel structure cost per square metre in South Africa?
There is no single figure worth quoting. Steel is a traded commodity, so the raw material price moves constantly, and the cost per square metre of your building depends heavily on span, eaves height and how much cladding you specify — two buildings of identical floor area can differ enormously. That is why we quote per job rather than publish a price list. Send us the size and the intended use and we will cost it properly; the quote is free.
What makes one structure cost more than another the same size?
Span and height first — both add steel to every frame. Then cladding: an open structure is far cheaper than a fully clad and doored one. Then site conditions, since coastal and high-lying sites attract higher design wind loads. Then options — doors, insulation, ventilators, Chromadek. And finally whether we erect it or supply it delivery-only.
Is it cheaper to build in steel than in brick?
For large clear-span buildings, usually yes, and it is faster. A portal frame reaches a weatherproof shell in a fraction of the time masonry takes, needs no wet trades for the structure, and puts no loadbearing walls inside the floor area. For small buildings the gap narrows, and for anything where thermal mass matters the comparison is not really like for like.
How long will it take?
It depends on the size, on how busy the factory is, and on your plan approval and foundations — which are usually the real constraint, not fabrication. We give a realistic programme with the quote rather than quoting a standard lead time we might not hold to.
Delivery, erection & export
Do you erect the structure, or just supply it?
Either. We deliver and erect throughout South Africa with our in-house erection team, which is what we recommend — the people erecting it work with these frames daily. For export and remote sites we supply delivery-only, flat-packed with every fastener and foundation bolt, for erection by a local team.
Do you export?
Yes. Since 1999 we have supplied structures into most African countries, several Indian Ocean islands and as far as Curaçao and Suriname — including a product store for a ruby mine in Mozambique, football stands, a skylight to the DRC and an overbuild over a war-damaged building. Export orders ship complete so that no fabrication capability is needed on site.
How do you handle a site with no fabrication facilities nearby?
Everything is fabricated, drilled and checked here before it ships, and on anything unusual we trial-assemble it in our own yard first — we did exactly that with the football stand that went to Mozambique. What arrives is a kit that bolts together to the drawing.
Can an existing structure be extended?
Along its length, straightforwardly — it means repeating an existing frame and continuing the sheeting. We have also built extensions tying into existing buildings, covered areas bridging two buildings, and a structure built over an existing damaged building. Widening an existing frame is a much larger job than lengthening one.
More detail per structure type: warehouses, farm sheds, aircraft hangars and carports.
Request a quote
Still not sure? Ask us.
We would rather answer a question before you order than fix an assumption afterwards.