Structural design for Nigerian building engineering — bungalows up to eight-storey frames. Load takedowns, column grids, bar bending schedules to BS 8666, costed quantities and drawings, from your phone or your browser.
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Nothing to download in the browser, and the same account either way — a project designed on the phone opens on the web. On a phone it can be added to your home screen, where it opens full screen like an app.
What it designs
- Whole-building takedown and per-column grid — every column designed where it actually stands, on an irregular plan or a building that steps in
- Every slab panel and every beam span, floor by floor, marked and scheduled
- Slabs, beams, columns (slender and biaxial), pad, strip and raft footings
- Stairs, lintels, and wind with sway and stability checks
- Fire resistance and robustness ties, reported on every building
- Detail drawings — a sheet per member with sections, dimensions, bar callouts and the schedule, as PDF or DXF
Every result is a step-by-step calc sheet: formula, substituted values and a PASS or FAIL on each check. Gravity-only designs stop at four storeys; above that a wind path is required, and the sheets say so. A building that steps in is gravity-only, because wind cannot be designed for a plan that changes at every level.
How it works
You enter geometry and loading; you get back the calculation you would otherwise have done by hand — formula, substituted values, PASS or FAIL — then a BS 8666 bar bending schedule, quantities priced with your own naira rates, DXF and PDF drawings, and the whole project as one branded report.
How tall it goes
| Path | Limit | Why it stops there |
|---|---|---|
| Gravity only | 4 storeys | No lateral load considered |
| Wind, braced walls or core | 8 storeys | Beyond needs dynamic wind and a stiffness analysis |
| Wind, moment frame | 8 storeys | Same |
A moment frame has its sway checked against h/500 and its stability index reported, so a first-order design says whether it is still valid. Wind is checked in both directions and the worse governs. The wind speed you enter is used as given — an effective gust speed at roof level, with no terrain or height factor applied on top.
Scope and limitations
A PASS means the design checks out for the loads entered, not that a building is safe to build. There is no seismic design, no piled foundation, and settlement is not calculated. Bar bending schedules use simplified anchorage and lap assumptions that are stated on the sheet and must be confirmed at detailing. Every output carries the licensed-engineer disclaimer, and a reviewing engineer is assumed.
Learn it, free
Seven worked examples to BS 8110, for students and for anyone coming back to this after a while: a load takedown, one-way and two-way slabs, beams, columns, pad footings, staircases and bar bending schedules. One building all the way through, and every number can be checked with a calculator.
Then strip and raft foundations, ground beams, lintels and wind loading.
Plus the reference tables and the practical decisions around them — rebar weights and steel areas, lap and anchorage lengths, cover, grades and mixes, span/depth ratios for deflection, how many bags of cement in a cubic metre, soil bearing capacity in Nigeria, what size a column should be, bungalow or duplex, BS 8110 against Eurocode 2, and what an approval submission contains.
And what happens to the design on site: reading a cube test result and when to strike formwork and props.
Questions engineers ask first
Which code does it use?
BS 8110-1:1997, as used in Nigerian practice, with BS 8666 for bar bending schedules and BS 6399-1 for imposed-load reduction on columns and footings.
Can I check the calculations?
That is the point of them. Every step shows the formula, the values substituted into it and the result, so a sheet can be worked through by hand. Nothing in the calculation path is generated by an AI model.
How tall a building can it design?
Four storeys on gravity alone, or eight with a wind path — braced walls, a core, or a moment frame. It refuses above that rather than returning a design it cannot stand behind.
Does the column grid have to be regular?
No. Columns can be taken out where there is a stairwell or an open bay, added where the plan has one off the grid, and moved, and the bays can all be different — fitted over the architect's drawing, read off it by a scan, or typed in from the dimensions. Every column is then designed on the tributary it actually carries. A building may also step in: a column stops at the storey the building stops at, and each floor is designed on the framing that storey gives it. A stepped building is designed for gravity alone, up to four storeys.
Does it design foundations?
Pad, strip and raft. There are no piles, and settlement is not calculated for any foundation type.
Does it produce drawings?
Yes — a detail sheet for each member on an A3 title block, drawn to scale, with sections and elevations, dimensions, bar callouts and the bar bending schedule beside the drawing, plus a foundation layout general arrangement, a column application plan — one per storey where the building steps in — and a framing layout for each floor and the roof. Export as PDF to issue, or DXF to open in AutoCAD. Laps and anchorages are still to be confirmed at detailing, and every sheet says so.
Is there an Android or iPhone app?
Yes — Structura is on Google Play and on the App Store, for iPhone and iPad. It runs in the browser too, on the same account, so a project designed on the phone opens on the web.
Can I put the browser version on my home screen?
Yes, and it is worth doing: it then opens full screen, with no address bar, and sits beside your other apps. Open Structura in the browser and it offers to install itself — one tap on Android, or Share then Add to Home Screen on an iPhone, which the app will walk you through. Nothing is downloaded from a store and your projects stay where they are.
Does it work offline, and where do my designs live?
Projects are saved on your device and backed up to your account, so a project designed on a phone opens in the browser. Running a design needs a connection, because the engine is on the server. Plan underlays never leave the device.
What does it cost?
Single members are free, however many you run. A credit unlocks one project — a whole-building takedown or a column grid — and revising, re-running and re-exporting that project stay free forever.
Credits
Single members — slab, beam, column, footing, stair, lintel, raft, wind — are free, however many you run. A credit unlocks one project: a whole-building takedown or a column grid. Revising that project, re-running it and re-exporting it are free forever.
| Building | Cost |
|---|---|
| Up to 3 suspended floors | 1 credit |
| 4 to 7 suspended floors (wind design) | 2 credits |
Sign in with the same account you use in the app. Paid by card, bank transfer or USSD through Paystack.