Basement wall design your plan checker can actually follow. Clause by clause.
Equilibrio designs propped foundation and basement walls to CSA A23.3 and outputs a permit-ready PDF — every number traced to its clause, every assumption printed, every limitation declared. Built for Canadian engineers who are done trusting inherited spreadsheets.
▸ Launching 2026 · Founding members lock CA$99/yr while subscribed · No spam, ~1 email/month
The current workflow
You inherited that spreadsheet. Would you defend it in discovery?
Every small firm in Canada designs foundation walls the same way: a hand-me-down Excel file, values retyped between tools, and an evening lost formatting the calc package for permit submission.
Untraceable spreadsheets
Locked cells, mystery factors, formulas last verified by an engineer who retired in 2011. You trust it because you have to — not because you've checked it.
Retyped everything
Soil pressures from one sheet, load factors from another, results retyped into Word. Every manual hop is a transcription error waiting for a plan checker to find.
Formatting, not engineering
The submittal is the product — and assembling one that a reviewer accepts without comments takes longer than the design itself.
How Equilibrio works
Inputs with guardrails. A trace you can audit. A PDF you can submit.
Declare your inputs
Geometry, backfill, surcharge, concrete and reinforcement. No silent defaults on soil parameters — you enter them from your geotech report or pick cited presumptive values, and the source prints on the output.
Audit the trace
Every intermediate value on screen with its A23.3 or NBC clause beside it. At-rest pressure by convention for propped walls, factored combinations shown, capacity checks pass or fail in plain sight.
p₀ = K₀·γ·H = 23.4 kPa [NBC 4.1.5]
M_f = 14.2 kN·m/m [NBC 4.1.3]
M_r = 21.6 kN·m/m ✓ 0.66 util [A23.3 Cl.10]
Export the package
A permit-ready PDF: cover sheet, design criteria, full clause-cited calculation, your firm's logo — and a declared-limitations page on every export. Ready for your review and seal.
The deliverable
Judge the report before you trust the tool.
This is what you're actually buying: a ten-page, clause-cited calculation package. Don't take the tour's word for it — download the full example and read it the way a plan checker would.
Download the example package (PDF)
Watermarked EXAMPLE · every check clause-cited · declared-limitations page + EOR review checklist included · Report ID on every page
Where it stands
Built for the gap the incumbents left open.
US tools don't speak CSA. Canadian tools don't do walls — or reports. Your spreadsheet does whatever it was doing in 2011.
| Inherited spreadsheet | US-code wall tools | Canadian calc suites | Equilibrio | |
|---|---|---|---|---|
| CSA A23.3 / NBC wall design | Unverified | No — IBC/ACI | No wall module | ✓ Native |
| Clause-cited calculation trace | Rarely | Partial | Partial | ✓ Every value |
| Permit-ready PDF package | Manual, hours | ✓ | Print-to-PDF only | ✓ One click |
| Declared limitations on output | — | Buried | — | ✓ Every page |
| French interface & reports | — | — | EN only | ✓ EN + FR |
| Public validation (KAT) log | — | — | — | ✓ Public |
Category comparison as of research date; verify current features before relying on it. "US-code wall tools" = IBC/ACI retaining-wall software; "Canadian calc suites" = NBC/CSA calculator platforms.
Declared limitations
What Equilibrio will never pretend to check
Most wall failures don't start in the stem — they start in what a calculator can't see. Equilibrio prints this list on every output, because a green checkmark should never imply more than it verified:
- Global (slope) stability
- Drainage adequacy & hydrostatic build-up
- Seismic site response
- Settlement & adjacent structures
- Backfilling before the prop exists
- Frost action beyond declared depth
These remain the responsibility of the engineer of record — and the tool says so, on paper, every time.
Why trust a new tool
Every calculation ships with a public Known-Answer Test log.
Before any check goes live, it must reproduce published reference solutions — worked examples from the CAC Concrete Design Handbook and standard Canadian texts — inside an automated test suite. The full log is public: the reference, the inputs, our result, the tolerance. A failing test blocks the release. You shouldn't take a stranger's word on structural software; you should be able to check it. So check it.
✓ KAT log publishes at launch · linked from every result screen
Pricing
Verify for free. Pay for the deliverable.
The full calculator is free to run — check our numbers against your spreadsheet all you like. The subscription buys the thing you actually bill hours for: the permit-ready package.
Free
CA$0
no account needed
- Full propped-wall calculator
- Live clause-cited results on screen
- Public KAT validation log
Professional
CA$99/yr
founding rate, locked while you stay subscribed · CA$19/mo after launch
- Permit-ready PDF export
- Saved projects & revisions
- Your firm's logo on reports
- Priority say on the roadmap
Questions engineers actually ask
FAQ
Is this engineering advice?
No. Equilibrio is a computation aid for qualified professionals. It performs arithmetic to declared methods and cites its sources; the engineering judgment, the applicability decisions, and the seal are yours. Every output states this, along with the full list of what was not checked.
What can I actually design today?
One module: propped (basement-type) reinforced concrete foundation walls to CSA A23.3:19 with NBC 2020 load treatment, including surcharge cases and the case where the water table sits above the footing. Wall height is bounded by slenderness (A23.3 Cl. 14.1.7.1), not by an arbitrary cap. That is the whole product today — deliberately narrow, thoroughly validated.
Not yet built, and not promised on any date: cantilever retaining walls, masonry stems, and automatic NBC climatic/seismic inputs for Québec and Ontario. These are sequenced by what founding members ask for. If you need those now, this is not the tool for you yet.
How do I know the numbers are right?
The Known-Answer Test log. Every check is validated against published worked examples before release, the tests run automatically on every code change, and the log — references, inputs, results, tolerances — is public. And because the calculator itself is free, you can also just run your last three projects through it and compare.
Where do soil parameters come from?
From you. Equilibrio refuses to assume a friction angle or bearing value silently: you enter values from your geotechnical report, or select conservative presumptive values with their citation — and either way, the source is printed on the output.
Can I submit the PDF for a permit?
The package is formatted for permit submission, but it isn't a permit document until a licensed engineer reviews it, takes responsibility, and seals it — the report says exactly that on its acceptance page, and includes a review checklist to make that step fast. Software output is not a sealed document; sealing is the engineer's act.
What happens outside the tool's limits?
It refuses, and tells you why. A wall too slender for its span, sloped backfill, out-of-range geometry or materials — each guard returns an explanation and what to do instead, not a number, because a wrong answer delivered confidently is worse than no answer. The limits are listed publicly with the KAT log.
Est-ce disponible en français ?
Oui — l'interface et les rapports PDF seront offerts en français au lancement. Des notes de calcul en français, pour des examinateurs francophones. (French interface and reports ship at launch.)
Who's building this?
Equilibrio is built by Known Answer Software, a one-person shop in Montréal working in the open — the validation log, the methodology, and the roadmap are all public. The company is named for the Known-Answer Tests every calculation must pass before release. Equilibrio and Known Answer Software are not affiliated with CSA Group, NRC, or any professional order.
Founding members
Fifty founding seats. CA$99/yr, locked for as long as you stay.
Founding members keep the launch price for as long as they stay subscribed, and get first say on what gets built next — cantilever walls, climatic auto-fill, or the O86 beam tool.