As express tunnel washes grow in popularity, many in-bay operators are left to wonder how they can compete. To address this challenge, we must first peel away a few layers. 

            Larger tunnel washes provide a speedy experience, often equipped with RFID chips or license plate readers to move cars through the wash swiftly. Lines that form move very quickly, and no one turns away.

Before and after of an in-bay to mini-tunnel conversion.

            With an in-bay automatic, commonly called a rollover in the industry, the customer enters an approximately 40’-45’ foot long bay where a large machine rolls over the car as it sits stationary. Most of these do not use friction-based materials but rather high pressure water along with very aggressive detergents to clean the vehicle. Once the cycle is complete, the customer pulls forward to the blowers at the end bay, and away they go.

            The in-bay wash cycle takes roughly seven to eight minutes on average. It is not uncommon for a wash to not offer a bailout lane that allows customers to get out of the line — if there are three cars ahead of them, their eight-minute wash just turned into 32 minutes. This leads to a suboptimal customer experience and is one of the main reasons these locations are decreasing in popularity. If a customer sees a few cars in line, they turn away.

            Some locations and/or municipalities do not allow large tunnel washes to be built, so in-bays still thrive in these places. Recognizing the growing demand for more wash options, if you are an in-bay operator or are considering purchasing a car wash, there’s a viable solution called a mini-tunnel or in-bay conversion.

            Part of the reason the ROI on a tunnel wash works so well is minimal labor; the same follows here: minimal labor is required. Some sites can run without any staff, but labor is recommended for at least the first few months while customers get acclimated to the new wash process.

            Below is a quick glimpse into converting a roll-over bay to a mini tunnel.

Preparing the Site

            The process starts with a thorough examination of the site to determine suitable traffic flow. Most in-bay sites are usually compact, featuring just one or two vacuums. With the equipment provider’s assistance, the operator must determine how to utilize the site best to ensure the new mini-tunnel is a success. A visually pleasing environment attracts customers, making them more likely to frequent the site after it has been updated.

            Operators generally need about a 40-foot tunnel to convert to a mini-tunnel. These washes need to provide the same clean car results available from a larger tunnel, and customers expect it to be fast —dual belt conveyors help move the process along nicely. With an in-bay automatic, at best, you are looking at maybe 10 cars an hour, compared to at least 40 cars an hour with a conversion.

            Once the site layout has been finalized and a strategic plan has been formulated, the demo process will begin on the inside of the wash — cutting the concrete in preparation to pour for the new dual belt conveyor. There are other options as well, like a surface conveyor that sits on top of the concrete. This is designed specifically for a very short tunnel and requires more concrete work outside the wash. 

Equipment Installation

            Installation of any new piping, if required, is the next step. Since the site is already a wash, it most likely will have an RO and/or a reclaim system — operators can reuse some of the existing tanks in the ground and potentially utilize existing chaseways for any new runs required.

            Installation of the wash equipment is next. This includes the wraps, mitters, rocker brushes, and arches.

            Following this, the installation of backroom equipment is the next priority. Reusing some of the existing equipment might be possible, but it is recommended to start fresh in most cases. Although most of the equipment is the same as used in larger washes, it can usually be stepped down since it will not be washing 150 cars per hour. This will help keep costs down and provide the most efficient wash. 

            Once complete, it’s time for a pay station update. Two lanes are recommended, if the site allows, so unlimited members can go through the line without waiting. New customers can simply use the pay station or attendee to get into the wash.

            In combination with a point of sale or other pay stations, license plate reader technology allows for a quick transaction. A mobile app can help set up new members, offer promotions, collect payments, and streamline the process.

            The last task undertaken involves fine-tuning the detergents and making any minor adjustments to the equipment, ensuring the optimal wash for customers.

            Once the in-bay conversion is complete operators must embark on a full-scale marketing blitz to drive new business to the site and make it stand out from the crowd.

Michael Van Wieren is a salesman at Tommy Car Wash Systems. He can be reached at (616) 330-4223 and