Abstract: Disclosed is a modular assembly device for providing adequate and efficient ventilation, temperature control, and insulation in poultry houses. The disclosed invention relates to an automated or manually-operated modular shutter system for tunnel ventilation in poultry houses, the system being self-sealed by the poultry house's internal negative static pressure. All the shutters in a modular shutter unit are designed to open and close in unison by means of specially-designed hinges and hinge spacers. In the preferred embodiment, there are four shutters per modular shutter unit, all of the same construction and dimensions. The shutters are designed with beveled horizontal edges and end cap seals, which together provide an efficient and practically airtight fit against each other when closed. The shutters are also of sufficient thickness to accommodate internal insulation if necessary to raise the insulation values needed for the poultry houses in cold winter months.