thick 4 u2032 u00d7 8 u2032 plywood sheets each ridge vent brace 38 is 8 feet long and base leg 55 is spaced from upper leg 58 by a distance just slightly greater than u00bd u2033 such as 9 32 u2033 or 5 16 u2033 in accordance with the invention the width of base and upper legs 55 and 58 can vary with base leg 55 preferably being more than twice the dimension of upper leg 55 to establish the j shape for instance base leg 55 can be made approximately 2 inches wide while upper leg 58 is approximately u00be u2033 wide as measured projecting from connecting leg 61 if desired greater dimensions can be employed such as base leg 55 being approximately 6 inches wide and upper leg being approximately 2 u2033 wide given this construction as shown best in fig2 each ridge vent brace 38 is adapted to slip over an uppermost edge 68 of a respective sheet of roof decking 20 with each ridge vent brace 38 extend rig along yet being spaced from peak 27 given the dimensioning of ridge vent brace 38 relative to roof decking 20 the uppermost edge of roof decking 20 is snugly received in channel 64 with ridge vent brace 38 being held down by the mounting of roof decking 20 to the respective rafter 42 43 thereafter ridge vent 34 is mounted along peak 27 and extends over the upper leg 58 of each ridge vent brace 38 more particularly ridge vent 34 is shown to include interconnected angled panels 78 and 79 each of which leads to a respective in turned portion 82 83 and a mounting flange.