Expansion joint and method

An expansion joint, comprising:

• a first hollow member comprising a plurality of adjoining walls that define a first cavity;
• a second hollow member comprising a plurality of adjoining walls that define a second cavity, the second hollow member configured to receive each of the plurality of adjoining walls of the first hollow member such that when the first hollow member and the second hollow member are coupled together an extended cavity is formed defined by the plurality of adjoining walls that define the first cavity and the plurality of adjoining walls that define the second cavity, the second hollow member further comprising a flange that is integral with and protrudes from an outer surface of the plurality of adjoining walls that define the second cavity, the flange and the adjoining walls forming an inner L-shaped ledge;
• a deformable seal coupled to the L-shaped inner ledge;
• a clamping seal flange not integral with the first or second hollow cavities, the clamping seal flange fastened to the second hollow member flange in contact with the deformable seal sitting on the L-shaped ledge such that the deformable seal deforms as the clamping seal flange is tightened to the second hollow member flange creating pressure on outside surfaces of the plurality of adjoining walls of the first hollow member thereby retaining the first hollow member within the plurality of adjoining walls of the second hollow member and forming a seal.