Geotextiles play a quiet but essential role in drainage systems. They separate soil from aggregate, allow water to pass, and help limit the movement of fine particles into drainage layers. Good performance starts with matching the fabric to the soil, water conditions, and project design.
Understand the job of the layer. A separator keeps dissimilar materials from mixing, while a filter allows water through and retains soil. In many applications one geotextile performs both functions. Confirm the design intent before choosing a product.
Check soil and flow conditions. Consider soil gradation, expected water flow, installation stresses, and the risk of clogging. The required opening size and permeability should be selected using project specifications and appropriate engineering evaluation, rather than relying on a generic rule of thumb.
Plan for installation. Prepare a stable subgrade, remove sharp debris, and place the fabric without wrinkles or excessive tension. Keep overlaps and seams consistent with the drawings and specification. Protect the fabric from construction traffic and repair any damage before placing aggregate.
Place drainage aggregate carefully. Dump and spread material in a way that avoids dragging or puncturing the fabric. Maintain the specified layer thickness and keep heavy equipment off unsupported fabric. Inspect the separation layer as work progresses, since damage may be hidden once it is covered.
Document and inspect. Record product identification, delivery lots, placement areas, overlaps, repairs, and inspection results. Photograph the exposed fabric and completed drainage layer at key stages. Follow the approved drawings, project specification, and manufacturer guidance for final acceptance.