Not to me.  I don’t think it says what you mean and could easily lead to litigation on a contested vote where the quorum is an issue.

If your board has an even number of members, there shouldn’t be a problem.  If you have 16 members, 50% is eight members so that a quorum would be eight plus one or nine members, which is a majority of the board.  But what if you have an odd number of members on the board, say 15 members?  In that case, 50% of the board is seven and a half members.  Add one more member and the quorum requirement is eight and a half members.  Since people don’t come in halves, I think you would have to round up to nine.  A quorum of nine members is 60% of the board, which is an extra person larger than a majority, which would be only eight.  (Some lawyer, of course, will argue that you round down in the calculation so that the quorum requirement really is only eight, but the language doesn’t say how to treat half a person.)

I assume that what the committee really wants is a quorum requirement of a majority, i.e. more than half of the board.  It is so much clearer to say that a majority of the board is required for a quorum. A third grader can figure out how many that is.  Lawyers can argue for years what it means to have 50% plus one.