Turf conditioning or "pitch heating" systems utilize plastic pipes installed within the soil layer of natural turf in outdoor applications such as stadiums, golf courses, and other field surfaces. Warm fluid is circulated through the embedded pipes or tubing to gently warm the grass roots to provide optimal root zone temperature for continued growth even in cold weather, and the potential to melt snow or ice.

Introduction

In practice, plastic pipes or tubing is installed within the soil layer of the natural turf, at specific depths as determined by the turf experts. Heated fluid is circulated at a controlled temperature to gently warm the grass roots, providing optimal root zone temperature.

Embedded soil temperature sensors guide the control systems to modulate heat input, as needed. Large surfaces are often split into multiple zones to respond to specific weather, wind and sun exposures.

These systems can extend the growing season of natural grass surfaces for use in late autumn and winter, allowing the fields to recover faster after use. It has been reported that warm soil is softer than cold soil or artificial turf, and can even reduce player injuries.

Turf conditioning systems may also melt snow, keeping playing surfaces accessible, visible, and safer.

Similar systems are also used in certain greenhouse applications with bedding plants and other types of plants.

Materials 

Several types of tubing represented by PPI's Building & Construction Division may be used for turf conditioning systems. These include crosslinked polyethylene (PEX) and polyethylene of raised temperature (PE-RT) tubing. In addition, polypropylene pressure pipe (PP) may also be used.

Design and installation support is typically available from the pipe system manufacturers.

Large turf conditioning systems often incorporate buried headers located in the sidelines or end zones of a football field, for instance. Buried headers, typically nominal pipe size 4 or larger, are often fabricated from polypropylene pressure pipe (PP) or high density polyethylene (HDPE) pipe.

Advantages

PEX, PE-RT, and PP tubing and pipe come in long lengths to assist designers with continuous loops under a field, when desired. These types of plastic tubing are flexible to ease installation and compatible with various types of antifreeze fluids.

Advantages of PEX, PE-RT, and PP tubing and pipe materials for this application include:

• Durability and toughness to survive job site installations
• Long coil lengths to reduce fittings or scrap
• Several fitting and joining options
• Flexibility to speed installation
• Lightweight, easy to transport
• Resistance to corrosion
• PP tubing allows for heat-fused connections throughout an entire system