Described is an insect net strip produced from a wide insect net which has been cut in a warp direction (xnet) by means of a one-step ultrasonic cutting and welding process. The insect net strip includes warp yarns and weft yarns extending substantially perpendicular to each other and at least 90% of the warp and weft yarns are monofilament yarns made of a thermoplastic material. After cutting and welding process the insect net strip has a first and a second edge extending parallel to said warp yarns each including a deformation zone being constituted by consolidated thermoplastic material deriving at least from said weft yarns. The deformation zone has a width (wdz) in the transverse direction (ystrip) of between 0.5-35 times the weft yarn diameter (we). At least 90% of gaps between adjacent weft yarns in the deformation zone are closed by consolidated thermoplastic material at least from the weft yarns which has been melted together to form a continuous or substantially continuous reinforced band-shaped edge portion of said insect net strip. The insect net strip is suitable for use in accordion-style constructions in greenhouse ventilation openings. A method for producing the insect strips is also described.