The Most Important Thing to Understand First: Designer vs. Installer
Hiring for septic work differs from hiring for most other trades because two distinctly different licensed practitioners are involved in most projects — and they are often separate companies. The SSSTS designer assesses your site and designs the system; the licensed installer builds it. Many property owners try to engage an installer first and discover that no work can begin without an approved design. Understanding this sequence is essential before making any calls.
Step-by-Step Hiring Process
Engage a Licensed SSSTS Designer First
A Small Sewage System Treatment Supervisor (SSSTS) is the licensed practitioner qualified to assess your site and design your system under Ontario Building Code Part 8. The SSSTS visits your property to conduct a site evaluation: measuring soil permeability through percolation testing, assessing depth to the seasonal high water table, mapping available area after setbacks, and evaluating slope and drainage. Based on this assessment, they determine which system type is appropriate and prepare the design drawings required for the RCDHU permit application.
Do not engage an installer before you have a designer. Without an approved design, installers cannot provide accurate quotes, and construction cannot legally proceed.
Obtain the RCDHU Permit
The SSSTS designer typically prepares and submits the permit application to the Renfrew County and District Health Unit (RCDHU) on the property owner's behalf, including the site evaluation results and design drawings. RCDHU reviews the application for regulatory compliance and, if approved, issues the permit. A permit must be in hand before any physical installation begins — this is a legal requirement under OBC Part 8, not a formality. Budget permit fees separately: typically $300–$800 depending on system type.
Get 2–3 Quotes from Licensed Septic Installers
Once you have the approved design drawings, you can solicit installation quotes from licensed septic installers. Provide the same design drawings to each installer so quotes reflect the same scope. Compare the full scope of each quote: Does it include excavation and backfill? Tank delivery and setting? Restoration of the site surface after installation? Is topsoil and seeding included, or is that a separate cost? What is the warranty on materials and workmanship?
Verify WSIB Clearance for the Installer
Request a current WSIB (Workplace Safety and Insurance Board) clearance certificate from any installer you are considering. WSIB clearance confirms the contractor carries active workplace insurance coverage. If a worker is injured on your property and the contractor does not have WSIB coverage, you may bear financial liability as the property owner. Verifying clearance is a straightforward step through the WSIB clearance certificate online portal. A contractor who hesitates to provide WSIB clearance is a red flag.
Confirm Permit and Inspections Are Included in the Contract
Your contract with the installer should explicitly state that all required RCDHU inspections will be scheduled and completed before work proceeds past each inspection stage. The contractor is responsible for notifying RCDHU when the system is ready for each inspection. If your contract is silent on inspections, address it in writing before signing.
The Excavation Inspection — Do Not Cover Until Inspected
RCDHU requires an inspection of the excavated leaching bed area before any material (gravel, pipe, fill) is placed in it. This inspection confirms that actual field conditions match the designer's assessment. If conditions differ — for example, bedrock is shallower than expected — the design may need modification before installation proceeds.
This inspection cannot be skipped or done retroactively. If the installer proposes covering the excavation before inspection to save time, decline. Doing so could result in orders to re-excavate and expose the system for inspection, at significant additional cost.
Get a Written As-Built Record of System Location
After installation, obtain from the installer a written diagram showing the exact location of the septic tank access lids, distribution box, and the perimeter of the leaching bed, with measurements from fixed points on your property (building corners, property line). This record is critical for future pump-outs (the hauler needs to find the access lids), for any future construction that must maintain regulatory setbacks from the system, and for disclosure when selling the property.
Red Flags to Avoid
- "We can skip the permit": Anyone offering to install a system without a permit is asking you to accept the legal risk, the liability, and the cost of remediation if discovered. There is no legitimate reason to skip the RCDHU permit process.
- Can't name the designer they work with: Some installers work with the same SSSTS designers regularly. If an installer is vague about who will design the system or suggests the design is unnecessary, be cautious.
- No WSIB clearance: Verify this before signing. It protects you.
- No written contract with inspection stages: A verbal agreement for work of this scope and cost is insufficient. Every material commitment should be in writing, including the inspection stages.
See also: Hiring a contractor in Ontario — general guide and Ontario contractor licensing guide.