Boiler house, late C19. Brick with pantiled roof, one storey, 3 bays. Front gable has, to left unglazed window; to right, blocked doorway both with segmental heads; beyond to right, 2 pairs of double garage doors with timber lintels. Above, single casement with segmental head. Interior has longitudinal dividing wall. Left side has single glazing bar fixed light. Detached chimney at rear, brick with rounded corners, has square base, projecting band, tapered square stack with cogged and corbelled cap. Approx 50 high. The building contained a boiler and steam engine used to supplement the windmill in times of calm and may have formed a self contained milling unit. Included for group value only. (NCC/js)