Sewer Lateral Inspections for Commercial Properties
What You Can't See Can Cost You — Underground Pipe Inspection Before You Close
A commercial building's sewer lateral — the underground pipe that connects the building's internal plumbing to the municipal sewer main — is one of the most consequential and most overlooked components in a pre-purchase inspection. It is invisible during a standard walkthrough, excluded from most general inspections unless specifically requested, and capable of producing repair bills that range from a manageable repair to a six-figure excavation and replacement project.
Calibre's commercial sewer lateral inspections use a camera-equipped pipe scope to inspect the interior of the lateral from the building's cleanout to the point of connection with the public main. What we find — or confirm is not there — gives buyers, owners, and lenders a clear picture of the underground infrastructure that no amount of above-grade inspection can reveal.
Why Sewer Lateral Condition Matters in Commercial Acquisitions
Commercial buildings place demands on sewer laterals that residential properties rarely approach. High-occupancy office buildings, restaurants with grease-laden wastewater, food processing facilities, healthcare properties, and retail centers with multiple tenant suites all generate wastewater volumes and compositions that accelerate pipe degradation. Combined with the age of many commercial lateral installations — clay tile pipe from the mid-twentieth century is still in active service in commercial districts across Idaho and the Inland Northwest — the risk of lateral failure in commercial properties is meaningfully higher than in residential construction.
The consequences of a lateral failure after closing range from a straightforward repair to complete replacement requiring excavation of parking lots, landscaping, or in some cases portions of the building slab. Understanding lateral condition before closing allows buyers to price that risk into the acquisition, request a credit or repair before close, or make a fully informed decision about whether to proceed.
What a Calibre Sewer Lateral Inspection Includes
• Camera Scope Inspection — a waterproof camera is inserted through the building's cleanout and advanced through the lateral to the public main connection, recording continuous video of pipe interior conditions
• Defect Identification — the inspection identifies root intrusion, pipe offset or misalignment, cracking, corrosion, collapse, grease buildup, bellying (low spots that collect solids), and deteriorated pipe materials including clay tile, Orangeburg, and corroded cast iron
• Pipe Material Assessment — the camera feed allows identification of the pipe material in use, which is critical for understanding remaining service life and the appropriate remediation approach
• Photographic and Video Documentation — all findings are documented with still frames and video footage referenced by pipe distance from the cleanout, included in the inspection report
• Written Report with Findings and Recommendations — a clear summary of lateral condition, defects identified, their location and severity, and recommendations for repair, further evaluation, or acceptance with noted risks
Pipe Conditions Commonly Found in Commercial Laterals
Root Intrusion
Tree and shrub root systems actively seek water and can penetrate the joints of clay tile and older concrete pipe, eventually causing significant flow restriction or complete blockage. Root intrusion is among the most common findings in commercial laterals that run beneath landscaped areas or near mature street trees, and it ranges from minor — easily cleared with routine maintenance — to severe, requiring pipe lining or replacement.
Pipe Offset and Settlement
Ground movement, soil consolidation, frost heave, and seismic activity can cause sections of an underground lateral to shift out of alignment, creating offset joints that restrict flow, collect solids, and become entry points for root intrusion. Settlement-related low spots — called bellies — allow solids and grease to accumulate rather than flow freely to the main, creating recurring blockage and odor issues.
Deteriorated Pipe Material
Clay tile pipe, which was the standard lateral material through much of the twentieth century, becomes increasingly brittle with age and is prone to cracking, joint separation, and collapse in commercial applications where loading from heavy traffic, delivery vehicles, or building additions has stressed the pipe over decades of use. Orangeburg pipe — a compressed fiber product installed from the 1940s through the 1970s — deteriorates from the inside out and is frequently found in commercial properties of that era in a state of partial or complete collapse. Both materials warrant careful camera assessment before any commercial acquisition.
Grease Accumulation
Restaurant, food service, and food processing commercial properties generate high volumes of grease-laden wastewater that accumulates on pipe walls over time, progressively restricting flow capacity. Even properties with grease traps can experience significant lateral grease accumulation, particularly in longer laterals or those with insufficient slope. Camera inspection reveals the degree of accumulation and informs decisions about remediation scope before closing.
When to Commission a Sewer Lateral Inspection
A sewer lateral inspection should be considered a standard component of commercial due diligence for any of the following:
• Pre-Purchase Inspections — any commercial property, particularly those built before 1980, those with clay tile or unknown lateral materials, or those in markets with mature tree canopy over or adjacent to the lateral path
• Restaurant and Food Service Properties — grease accumulation and high-volume wastewater make lateral condition assessment essential before acquisition
• Multi-Tenant Commercial Buildings — shared lateral infrastructure serving multiple tenants creates higher cumulative demand and accelerated wear
• Properties with Known Drainage History — any property where slow drains, recurring backups, or odor issues have been reported by tenants or disclosed by sellers
• Older Downtown Commercial Stock — established commercial corridors in Boise, Nampa, Spokane, Pocatello, and other Inland Northwest cities frequently have lateral infrastructure dating from the early-to-mid twentieth century
• Lender Requirements — some lenders require lateral inspection as a condition of financing, particularly on food service properties or older commercial buildings
Sewer Lateral Inspection as Part of Complete Due Diligence
A sewer lateral inspection is most effective when combined with a full commercial building inspection, ensuring that underground infrastructure findings are integrated with the above-grade assessment into a single, coherent due diligence picture. When lateral defects are identified, Calibre can incorporate the repair cost estimates into a Cost-to-Cure Report, giving buyers a complete financial picture of the property's condition — above and below grade.
Coverage Area
Calibre provides commercial sewer lateral inspections across Idaho, Eastern Oregon, and Western Montana. See our Areas Served page for city-specific coverage and service availability.
Schedule a Sewer Lateral Inspection
Contact Calibre today to add a sewer lateral inspection to your commercial due diligence package or to schedule a standalone lateral assessment for a property you own or manage.
📞 (208) 305-6245 | ✉ Schedule@CalibreCBI.com
Frequently Asked Questions
Is a sewer lateral inspection included in a standard commercial building inspection?
Not automatically. A sewer lateral inspection requires a separate camera scope and is typically ordered as an add-on to a commercial building inspection or as a standalone service. Calibre recommends commissioning a lateral inspection alongside any pre-purchase commercial building inspection on properties built before 1980 or any food service, restaurant, or high-occupancy commercial property.
How long does a sewer lateral inspection take?
Most commercial sewer lateral inspections take between 45 minutes and two hours depending on the length and configuration of the lateral, the number of cleanout access points, and the complexity of the building's internal plumbing connections to the main lateral. Properties with multiple tenant connections or unusually long laterals may take longer.
What if there is no cleanout access?
If the property does not have an accessible cleanout, the lateral can often be accessed through a roof vent stack. In some cases, installing a cleanout may be necessary to perform the inspection. We will confirm access conditions during the pre-inspection consultation and advise on the best access approach for your specific property. If we are not able to access the sewer lateral, we will report on that defect without charge to the you, the client. Please note that we do NOT pull toilets.
Can a damaged lateral be repaired without full excavation?
In many cases, yes. Trenchless pipe lining — a process in which a resin-saturated liner is inserted and cured inside the existing pipe — can repair cracks, offset joints, and root intrusion damage without excavation, at a fraction of the cost of full replacement. The viability of lining depends on pipe condition and configuration, which the camera inspection helps determine. Where lining is appropriate, it is a significantly more cost-effective remediation than open-cut replacement.
How do findings get incorporated into the acquisition process?
Lateral inspection findings are documented in a written report with video and photographic support. If defects are identified that warrant repair, Calibre can incorporate repair cost estimates into a Cost-to-Cure Report, giving you a single integrated document covering all property deficiencies — above and below grade — with associated cost opinions for negotiation or capital planning.