Interlock Ottawa Group provides professional Interlock design & installation services in Ottawa Ontario. Free In-Home Estimate for Interlock Stone Driveways, Patios, Walkways, and Retaining walls. Payments Accepted: Cash, Cheque Year Established: 2013 Product/ Services: Interlock Services Interlock Patios Outdoor patio Interlock Walkways Interlock Driveways Retaining Walls Additional Features: Fully Certified ...