Abstract: Bridging for joists that does not interfere with the installation of heat and air conditioning runs is provided by longitudinally spaced, transverse plate members which extend between the joists and have a span that may be varied to accommodate a particular joist spacing. Each of the plate members presents a major surface that is disposed in an upright plane, a central opening being provided through the surface for receiving a longitudinally extending conduit. The openings in the spaced plate members are aligned so that the conduit may be readily installed and supported by the plate members. The bridging, therefore, enhances the structural rigidity of the joists and supports the conduit in the space between the joists without interfering with installation of the conduit.