Window

A frame assembly for a thermally efficient multi-paned window, comprising:

• (a) a plurality of frame rails each including a central section;
• (b) a respective side section configured to mate with each said central section along one side thereof;
• (c) respective pane cavity means, defined between said central and side sections, for receiving a peripheral margin of a window pane;
• (d) connection means for attaching each said side section to the respective central section while permitting movement of said side section relative to each said central section in order to apply pressure along said peripheral margin of said window pane within said pane cavity means, said connection means including respective innerlocking lip portions associated with each said central section and said side section;
• (e) locking means associated with each said central and the respective side section for urging said side section relative to said central section in a manner to apply said pressure and sealingly hold said peripheral margin in said pane cavity means;
• and
• (f) said connection means being located outwardly adjacent said pane cavity means, and said locking means including spine means for extending along the said frame means exterior of said connecting means for urging a portion of said side section away from said central section and pivoting said side section about said connection means and urging an upper portion of said side section toward a portion of said central section, providing compressive force against said peripheral margin.