How to choose Best Sub-Base for Artificial Grass?

In today's booming global artificial turf industry, choosing the right sub-base has become a key factor in ensuring the performance and durability of your turf. Whether in the arid Middle East or rainy Southeast Asian countries, the choice of sub-base has a direct impact on the drainage, stability and longevity of the turf.

 

In this article, we will analyze the concept of artificial turf sub-base, common types and their key roles, as well as provide guidance on material selection and construction for different application scenarios, so as to help the global B-end customers to achieve long-lasting, smooth and permeable high-performance paving effect in the high-quality artificial turf projects of Linwoo factories.
 

Types of artificial turf substrate
Crushed Miscellaneous Base
Crushed Miscellaneous Base (CMB): a mix of recycled concrete, asphalt, and gravel, ranging from 3/4″ to fine sand, well-drained and relatively low cost after compaction, optimal for landscaping and residential yards.

Class II Road Base (CMB): Similar in appearance to CMB, but with a stricter particle gradation, it is commonly recommended by manufacturers as a standard subbase material. A 2-3″ thick stone is placed after 2-3″ of soil is removed and compacted in a two-way ring, providing excellent load-bearing capacity and drainage when constructed to standards.

1/4″ minus (#4 stone): common in the U.S. market, is actually a small particle size under-screen material (screenings), both sand and stone chip characteristics, suitable for sites with high settlement control requirements, such as golf putting greens.

 

Decomposed Granite (DG)
Decomposed granite is crushed to form fine particles with good water permeability, solid and stable, especially suitable for sites requiring high precision leveling, such as golf greens and training grounds.

Sand and Gravel Mixed Substrate
It is made of appropriate amount of medium sand mixed with small grained gravel, which not only ensures drainage, but also utilizes sand to fill the gap of gravel to realize good compaction, which is an economical choice for multi-functional sports ground and roof platform.

 

Other Special Substrates
Concrete or asphalt subfloor: When the project itself already has a solid bearing surface (such as old parking lots, indoor venues), you can directly lay anti-grass cloth on it, without additional gravel subfloor.

Wooden structural flooring: Mostly used for indoor or temporary event venues, with polyurethane underlayment or EVA foam layer to enhance comfort and sound insulation.
 

Why Choose the Best Sub-Base for Artificial Grass?

• Extend the service life: High quality underlayment can effectively resist settlement and heavy pressure, reduce the frequency of post maintenance, and the theoretical service life can be more than 10 years.
• Improve safety and comfort: the cushioning and fastening effect of the sublayer reduces the hardness of the ground, reducing the risk of injury and improving the experience of athletes and the public.
• Optimized Drainage: Rapidly removes rainwater and clean water, eliminating standing water, mud or algae growth and ensuring all-weather usability.
• Saving operating costs: a one-off subfloor construction avoids repeated reworking or repairing, reduces waste of labor and materials, and delivers a higher return on investment.

 

How to choose the best artificial turf underlayment? (Different scenarios)
Landscaping and Residential Courtyard
Recommended material: CMB or Class II paving stones, thickness about 3-4″.
Reason: cost-effective, stable drainage, good compaction, suitable for light tread and landscape arrangement

 

Outdoor Sports Ground (soccer field, basketball court, track and field)
Recommended Material: Class II paving stones or mixed sand and gravel sub-base, 4-6″ thick with ≈1″ thick silica sand or rubber granule fill in the top layer.
Rationale: To meet the needs of heavy-duty use and high-speed sports, taking into account the elasticity, resilience and drainage performance.

 

Golf Putting Green
Recommended Material: Fine-grained DG or 1/4″ minus, 2-3″ thick, no surface fill.
Reason: Ensures ultimate flatness and fine drainage, simulates the feel of natural greens.

 

Roof Decks and Patios
Recommended Material: Sand and gravel mix or specialized lightweight polymer underlayment, 2-3″ thick.
Reason: Reduce weight, water permeability and cushioning, use with impermeable and insulating layers.

 

Indoor Multi-purpose Ground
Recommended material: ready-made concrete or wooden floor + grass cloth + EVA or PU backing.
Rationale: No additional foundation excavation, fast construction and good mobility.

 

How to install the bottom layer of artificial turf?
Site preparation
Clear the site of debris, vegetation and surface soil, mark out the paving range. If there are drainage pipes or cables underground, they need to be buried or protected in advance.

Excavation and preliminary leveling
According to the thickness of the selected subgrade, excavate 2-6″ soil layer and do rough leveling (1-2% slope can ensure drainage).

Use laser grader or line drop to measure the height to make sure the longitudinal and transverse slopes meet the design requirements.

 

Pave anti-weed cloth (optional)
Lay a permeable membrane or HDPE grassproof cloth on the bare soil surface to deter weed growth. Reserve corresponding overlap length at the interface between the edge and the subsequent sublayer.

 

Laying and compaction of sublayer materials
Lay gravel, DG or sand and gravel mix evenly in layers, each layer about 2″ thick. Use 800-1200 kg roller or hand-held vibrating rammer, first clockwise, then counterclockwise compaction for several times, until the surface layer is solid, no loose feeling.

 

Fine sand leveling layer (if required)
For stadiums and residential yards, an additional layer of ≈1″ medium sand can be laid and scraped with a long wooden board to ensure surface flatness. Finally, do a light pressure to make sure the sand layer is fixed and there is no obvious mark.

 

Laying artificial turf
Place and stretch the grass carpet to the state of stress band, use special tape or hot melt adhesive at the splices. Fix along the edges and use U-shaped nails or ground anchors at the periphery. Sprinkle in silica sand or rubber granules as needed and vibrate brush with mop bristles until fibers are upright.

 

Conclusion
Artificial turf sublayer is the "skeleton" and "drainage organ" of the whole paving system, which plays a crucial role in the use performance and life span. Correctly understanding the characteristics and application scenarios of various types of underlayment materials, combined with high-quality raw materials and step-by-step construction preparation, layering and compaction, can provide customers with cost-effective, low-maintenance, highly durable artificial grass solutions. Whether it is a home garden, commercial plaza, sports stadium, or rooftop terrace, choosing the right substrate and strictly enforcing the construction standards can truly realize the ideal effect of "evergreen and stable". B-end customers are welcome to communicate further with Linwoo team, we can provide you with high quality artificial turf.