Warranty Details & Instructions

Selvage Concrete has been manufacturing quality precast products for the nine counties in the Greater Bay Area since 1951. Our concrete tanks are designed by structural engineers to meet UPC/ASTM standards, and are certified by IAPMO.

Installation Detail & Instructions for Warranty of Concrete Tanks
(Warranty will not be honored if installation and water testing requirements are not followed.)


Trench must be excavated to provide 12–14 inches of clearance around sides of the tank to allow for the removal of lifting equipment. Recommended coverage over the tank is a maximum of 36 inches, and the trench bottom should be level, compacted soil.


Backfill used may be the local virgin soil and be free of large rocks, or other suitable backfill can be used, i.e. sand, pea gravel, and etc. In the case of high water table areas, the tank should be filled with water to prevent it from floating. It is recommended that heavy equipment not be operated over any tank systems not certified as traffic rated.  Water testing must be done only AFTER backfilling completely around tanks to within two inches below the outlet (see item #5 – c. below).


Our Tanks are IAPMO Certified and meet the highest standards for manufactured concrete tanks. Onsite inspections are performed by IAPMO as required to assure they meet those ttandards. Before shipping each concrete tank is inspected to assure its correctly sealed and properly labeled per IAPMO specifications. Each concrete tank is supplied with required fittings for the inlet and outlet. The four-inch inlet and outlet connections are inspected to assure the connecting pipes may be connected in a watertight manner.

When installing cribbing or sleeves on septic tanks, the directions for installation and precautions regarding cribbing or sleeves around the manhole must be in compliance per the manufacturer’s recommendations for the product used, i.e., Orenco Systems, Polylok Products, etc.


The installing contractor is responsible for on-site water pressure testing of each concrete tank per IAPMO specification and/or the local ordinance requirements in their area.


a. Selvage Concrete Products, Inc. guarantees our concrete tanks meet all requirements of the Uniform Plumbing Codes and IAPMO™ specifications for design structural criteria and are suitable for residential septic tank use.

b. Selvage Concrete Products, Inc. concrete tanks are warranted against manufacturer defects for a period of ten (10) years from the date of manufacturing.

c. Tanks are required to be backfilled completely around the tank BEFORE water testing. Backfill should be to within two inches below the outlet and compacted. Backfill may be local virgin soil, free of large rocks, or other suitable backfill can be used, i.e. sand, pea gravel, etc.

d. The water level during testing should NOT be higher than TWO INCHES into risers, cribbing or sleeves. (Please call us at (707) 703-1444 if you have any questions or concerns about this process)

e. Selvage Concrete Products, Inc. guarantees if the tank does not pass the water test when properly water tested, Selvage Concrete Products, Inc. will come on site to inspect the tank at their option, and repair or replace the tank to assure it will pass the water test.

f. The warranty, including the option to repair or replace the tank, will not be honored if above installation and water testing requirements are not followed.

The above instructions, requirements and warranty program, including design criteria and/or specifications, layouts, technical drawings, names and services are subject to change without prior notice. Contractor/Installer or homeowner is responsible for staying in compliance with these requirements and staying current with any changes made herein.

Concrete Tanks Warranty in Santa Rosa

Santa Rosa, Petaluma, Vallejo, Napa, Novato, Rohnert Park, Fairfield & San Rafael