SO http://is.gd/ysYFt8

HTML

<link rel="stylesheet" href="http://getbootstrap.com/dist/css/bootstrap.css">
<div class="">
    <div class="row">
         <div class="col-sm-12 ">
               <h1>Header</h1>
        </div></div>
      <div class="row col-wrap">
          
          <div class="col-md-3 col"><h1>Nav</h1></div>
        <div class="col-md-9 col">
            <h1>Content</h1>
            <p>Lorem ipsum dolor sit amet, eam dictas utamur vituperatoribus ei, alii idque invenire eu eum. Mei ut patrioque consequuntur, utinam delenit has id, ut natum officiis vix. Vel eu equidem laoreet, an sit delicata partiendo interesset. Oratio quidam suscipiantur usu ei.
  </p>
  
        </div>
      </div>
    </div>

CSS

.col{
    margin-bottom: -99999px;
    padding-bottom: 99999px;
}

.col-wrap{
    overflow: hidden; 
}


/* following styles for illustration only */
.col-md-3{
    background-color:#ffc;
}
.col-md-9{
    background-color:#ccc;
}

.col-xs-12{
    background-color:pink;
}