FIELD: manufacture of greenhouses from hollow plastic pipes. SUBSTANCE: method involves connecting longitudinal and transverse hollow pipes of greenhouse by heating to plastic state of material of longitudinal portion; forming through cut on this portion; introducing into said cut mandrel having diameter at least equal to that of transverse portion, with through cut being formed on longitudinal portion before heating of longitudinal portion to plastic state of material and having length not in the excess of 1.5 the diameter of transverse portion; assembling longitudinal and transverse portions; expanding hollow ends of member to the size of outer diameters of longitudinal and transverse pipes of carcass by heating ends of cross-shaped connecting member in the range of 150-220 C, with following reducing of heating temperature to 100-150 C from edge of said member to its central part at a distance of at least 10 mm; using sharpened end of transverse portion as mandrel to be inserted into longitudinal portion th
