Seal Guard Lip & Tape System provides users with an efficient means and method for applying underlay for various types of flooring. The system entails the joining of two laminate floor underlay sections to create a vapor barrier. The vapor barrier provides superior sealing by utilizing vapor barrier tape with release liner, and also reduces harm to installed flooring. Seal Guard Lip & Tape System may comprise foam underlay with vapor barrier qualities, vapor barrier tape, and release liner, all of which can be laminated together. The specially formulated vapor barrier tape can be attached to a 1½″ release liner, which may be made of siliconized paper plastic, covering approximately half of the tape. The vapor barrier tape/release liner combination may be joined to the laminate underlay with 1½″ of the tape and liner exposed beyond the foam underlay. The entire assembly can be easily affixed to an adjacent underlay sheet, thereby creating a sealing means.