Installation Guidelines
Solmax's guideline for placing geotextile or geogrid on soft subgrade under an aggregate section: how to prepare the surface, which way to unroll, how much to lap, and how to get the first lift of fill on without damaging what you just laid.
The part that gets skipped most often is the first one: unroll in the direction of travel, so the machine direction of the roll runs with the traffic, and get it flat with no folds or wrinkles before any fill lands on it. A wrinkle becomes a fold under the first loaded truck, and a fold is a line with no tensile capacity across it.
Two things in here are worth reading even if you have installed fabric a hundred times. Over very soft subgrade, below about CBR 1.5%, the guide calls for low-ground-pressure equipment and tells you to stay off the vibratory compactor, because the crust you are driving on is doing more work than it looks like. And it says to leave root mats where they are, cutting stumps flush rather than grubbing them out, which is the opposite of what most crews expect.
Overlap depends on how soft the ground is, and it is not a fixed number. If you want the quantity worked out for you, our roll calculator takes the overlap and the site dimensions and tells you how many rolls to order.
Road Fabrics stocks the fabrics and grids this guide covers, and installs them. If you would rather hand the placement to a crew that does it every week, ask us for a quote.
Tell us about your site and performance goals. Our team will match the right materials and installation approach, and get you a quote fast.
