Abstract: The invention provides a window frame construction system (10) comprising an inner frame (12), an apertureless outer frame (18) provided with at least abutment surface (22) projecting towards said inner frame (12) and a plurality of aligning connector units (26) for attaching said inner frame (12) inside said outer frame (18), said unit comprising, a hollow body (28) attachable to said inner frame (12), a nut plate (34) engageable with said inner frame (12) and having an internal screw thread (36) matching an externally screw-threaded portion of said hollow body (28), whereby said hollow body (28) may be adjusted to project a desired distance outwards from said inner frame (12) towards the outer frame (18), and a first rotatable member (40), insertable in a hollow body (28), wherein said first internal rotatable member (40) is provided with a projection (42), an end portion (44) of which faces outwards towards said outer frame (18) for effecting engagement and alignment between said inner and outer frames.

Abstract: Method for forming an enclosure of the type having a plurality of enclosure panels and at least one door, comprising: providing a first flexible profile element (12) web (14) dividing said element into an upper channel (16) bounded by a pair of spaced-apart, upwardly extending arms (18, 20) of unequal height, and a lower channel (22) bounded by a pair of spaced-apart downwardly extending legs (24, 26) being provided with an inwardly directed flange (28) for receiving and retaining at least one rigidifying metallic strip element (30), said upper arms (18, 20), having inwardly directed interfacing portions (32) for receiving and retaining an enclosure panel (34) inserting a metallic strip (30) into said lower channel (22) formed in said flexible profile element (12) to form a rigid composite base element; and inserting a plurality of enclosure panels in said upper channel to form the walls.