Ontario Septic Designer
Straight answers.
Grouped by who is asking. Every answer links to the page that expands on it.
Is it legal to design my own septic system in Ontario?
Yes, for your own system on your own property. The Ontario Building Code normally requires a septic designer to hold a BCIN (provincial designer registration), but Division C, Sentence 3.2.5.1.(3), clause (d) exempts a person whose design work is only for a sewage system that the person will build and that the person owns. In plain terms: design it, own it, build it, and you do not need a BCIN. You still need a sewage system permit from your township, health unit or conservation authority, the design still has to meet Part 8, and the inspector still checks the work. Some township web pages only mention BCIN designers; if the counter clerk asks, point them to Div. C 3.2.5.1.(3)(d).
Can I install it myself too?
Yes. Installer registration under Division C, Section 3.3 applies to people in the business of installing sewage systems. An owner building their own system on their own lot is outside that rule. The permit and inspections still apply, and you can hire an excavator operator by the hour and still be the builder.
Can it calculate daily design flow?
Yes – the full Table 8.2.1.3.-A logic: bedrooms, floor area brackets, fixture units, with the highest applicable additional flow, and the math shown step by step.
Can it generate permit worksheets and a soil cross-section?
Yes. Every worksheet the package needs, plus a clean SVG cross-section drawn from your soil layers, water table, bedrock and separations.
Can it calculate trench length and filter bed area?
Yes – L = QT/200 (or /300 with a treatment unit) with the 40 m minimum, and filter bed effective and contact areas with the loading-rate caps.
Does it check setbacks?
Yes, against the correct clearance table per component – tanks and beds are never treated the same – with plain-English pass/fail lines.
Can I save templates?
Duplicate Project deep-copies any past job – inputs, rates and all – which is how repeat Class 4 work becomes minutes instead of hours.
Does it replace professional judgment?
No. It calculates, checks, drafts and organizes. Your qualifications and judgment stay yours.
What is included at launch, and what comes later?
Launch: residential Class 4 – trench, filter bed, raised versions. Later: shallow buried trench, Type A/B dispersal beds, treatment unit database.
Is this a permit?
No. The local building department, health unit, or approval authority issues permits. This prepares the package you hand them.
What does the township still control?
Everything that matters: review, inspections, and approval. A complete package makes their review smoother – it does not replace it.
What are the refund terms?
Full refund on the $99.99 package before your first PDF export, none after. Plain-language details on the refund policy page.
What if my flow is over 10,000 L/day?
The workflow stops. Systems that size are outside ordinary small sewage system scope and need an engineer and a different approval path.