Capital expenditure and exploitation costs of ventilation systems with longitudinal counterflow spiral recuperators are minimized taking into consideration the results of measurements and calculations together with the well-known effectiveness-NTU method. It was estimated that ventilation system with longitudinal flow spiral recuperators refunds the capital expenditure within 2 or 3 years. Due to their advantages, spiral recuperators with the longitudinal counter current flow should be widely utilized for ventilation systems in winter and cool recuperation in summer. (C) 2008 Elsevier B.V. All rights reserved.