Effective drainage is critical for protecting structures and infrastructure against water damage and erosion. Whether managing stormwater runoff, foundation drainage, or wastewater from septic systems, having the right materials for transporting water away from sites is essential.
While single wall pipes made of PVC, polyethylene, or corrugated metal have traditionally been used, these options have limitations in terms of strength, durability, and flow capacity. This is where triple wall drainage pipes truly stand out.
Introduction to Triple Wall Drain Pipes
Triple wall drainage pipes, as the name suggests, have three layers fused together into one highly robust pipe structure.
What is a Triple Wall Drain Pipe?
A triple wall drain pipe consists of three bonded layers of high-density polyethylene (HDPE):
- A smooth interior wall
- A corrugated structural core
- A smooth exterior wall
This unique 3-layered construction provides exceptional stiffness and strength compared to traditional single wall HDPE or PVC pipes. The corrugated middle layer maximizes structural integrity, while the smooth inner wall facilitates water flow.
Key Components – 3 Bonded Layers
The key advantage of triple wall piping comes from having three fused layers working together. An inner smooth wall maintains water flow while preventing buildup. A waffled or corrugated center structural core provides exceptional resistance to crushing. The outer layer adds further structural strength and protects the core.
The layers are bonded through a thermal fusion process under heat and pressure, creating seamless pipe sections. This eliminates risk of leakage between layers over time.
Applications Utilizing Triple Wall Pipes
With their unsurpassed strength and water flow traits, triple wall pipes are commonly used for:
- Foundation drainage
- Retaining walls
- Septic system leaching fields
- Irrigation lines
- Landscape drainage
- Stormwater runoff management
- French drain systems
Benefits of Using Triple Wall Piping
From a performance standpoint, triple wall drainage systems have distinct advantages over single wall pipes:
Exceptional Durability and Pipe Stiffness
The tri-layer bonded composition makes these pipes incredibly stiff and crush resistant. With added layers reinforcing them, triple wall pipes have a Standard Pipe Stiffness rating double or triple that of single wall HDPE or PVC options.
This allows them to withstand significant pressures from soil, structures, and dynamic loads without damage or loss of hydraulic capacity.
Withstand Heavy Pressures Without Damage
Due to their high stiffness, triple wall pipes maintain shape and water flow capacity even under unusually heavy loads. For instance, they can endure H-20 vehicle loading without failing.
The heavyweight capacity makes them suitable for heavy-duty applications like roads, railroads, airport tarmacs and retaining wall drainage.
Superior Abrasion and Corrosion Resistance
The durable polyethylene construction also resists abrasion, corrosion and chemical degradation exceptionally well. This prevents wear and damage during installation and use within aggressive soil or wastewater environments.
As a result, triple wall piping enjoys a long service life with strength persisting for decades.
Increased Flow Rate Capacity
The slippery interior wall lined with polyethylene maximizes flow rates. The lack of friction allows piping to move 50-80% more water compared to corrugated single wall pipes. This gets sites dried out faster!
Triple Wall Drain Pipe Construction
Triple wall piping has specialized construction with three distinct layers molded together to take advantage of each material’s inherent strengths.
Smooth, Glossy Interior Layer
The interior features a smooth waterway made using slick polyethylene. This allows water, wastewater or other fluids to flow freely through the pipe without buildup.
Corrugated Structural Middle Layer
A corrugated profile makes up the core structural layer. The waffled fluting arrangement adds incredible stiffness, resisting vertical deflection. This prevents the pipe from being crushed under heavy dynamic or static loads from above.
Smooth Exterior Final Layer
The third external layer encases the corrugated middle section in smooth polyethylene. Having a smooth barrier on both interior and exterior sides boosts flow rate capacity as well as corrosion and abrasion resistance.
Unique Fused Layer Bonding
Rather than having separable layers, triple wall pipe sections have fused bonding between layers. This makes delamination or separation impossible. Thermal bonding eliminates weaknesses at the layer interfaces over decades of pipe service.
Unique Properties of Triple Wall Pipes
Beyond just having more layers, the composite 3-layer HDPE makeup directly enhances performance metrics:
Significantly Higher Impact Resistance
The thick triple wall cross section better distributes and absorbs impacts without damage. This prevents punctures and perforations during installation and operation near dynamic load environments.
Flexibility and Ease of Handling
Even with added layering, triple wall HDPE pipes maintain reasonable bend radius flexibility. This simplifies maneuvering them into place down trenches.
Their lightweight compared to concrete piping also improves ease of handling. Contractors avoid back strains and fatigue placing long triple wall pipe sections.
Lightweight Compared to Concrete Pipes
At under one-fifth the weight of concrete, triple wall’s lightweight HDPE construction better facilitates installation. Their slimmer trenching needs also reduce excavation costs compared to heavy precast concrete methods.
Integral Coupler Connections
Molded-in couplers integrated into one or both ends of pipes simplify connecting section lengths together. The coupler ends have a slightly larger diameter to join over the non-bell ends.
Having couplers fused to pipe walls rather than glued on prevents disconnects or leaks at joints.
Triple Wall Pipe Strength Testing
Significant testing during research and development validates the long-term performance benefits of triple layered pipe walls over single layer designs:
Pipeline Pressure Testing
Hydrostatic strength evaluations involve containing high water pressure within pipes up to levels matching their maximum working pressures. Monitoring confirms triple layer systems withstand over 3 times the pressure before buckling versus single wall types.
Structural Strength Testing
Crush testing examines vertical load capacity within a test box applying sideways pressure. At a specific pressure, single wall pipe walls crack and deform. Triple wall specimens support over twice the load before reaching this failure point.
Results vs Single Wall Pipe Performance
In repeated testing, triple layer pipes outperform equivalent single wall HDPE and PVC piping on metrics like crack resistance, impact strength, and deformation resistance. This confirms their long term sturdiness benefits.
Most Common Applications of Triple Wall Pipe
Triple wall piping reliably serves critical drainage functions across municipal, residential and commercial settings:
Foundation Drainage & Retaining Walls
Their crush strength makes triple wall pipes ideal for structural drainage roles. As foundation footer drains or backfill for retaining walls, they prevent pooling near buildings while shielding against compression.
Septic System Leach Fields
In leach fields or French drain configurations, triple wall durability withstands acidic conditions from wastewater effluent over longevity matching the septic system itself.
Downspout Runoff Management
The exceptional flow rates make triple wall piping well-suited to divert rain gutter downspout water. They rapidly channel roof runoff away from homes.
Drainage for Landscaping Areas
Around gardens, lawns or playing fields, triple wall French drains, catch basins and connectors keep the subsurface dry. Their flexible polyethylene construction better handles freezing, thawing and light ground shifts.
Irrigation and Sump Pump Discharge
In agricultural irrigation roles, triple wall durability handles repeated dynamic loading from heavy mobile equipment. Around sump pumps, the exceptional crush resistance prevents discharge line failures.
Installing Triple Wall Drain Pipes
Proper triple wall pipe system placement ensures optimal drainage performance long-term:
Equipment Needed
Installation requires common digging tools like trenchers and excavators. Joining connections rely on solvent cement, standard couplings and elbows/tees matching triple wall dimensions.
Pipe Bedding Requirements
The underlying fill should have fine drainage aggregates like sand, gravel or crushed stone. This supports members along their length and promotes water flow under piping.
Proper Slope and Placement
Maintenance of at least 1% slope facilitates appropriate flow rates. Branching layouts need positioning according to code spacing rules below frost lines or slab edges.
Connecting Pipe Sections
Fusion welding, flange joints or snap-fit bell/spigot designs allow connecting the HDPE pipe lengths end-to-end or to drainage accessories. Sealing strips prevent soil backfill intrusion.
Backfilling the Trench
Cushion layer backfilling over pipes with drainage aggregates protects against weight loads. Further light fill and compaction rebuilds the trench profile.
Triple Wall Vs. Single Wall Drain Pipes
Examining key differences in makeup and performance helps illustrate triple wall pipe advantageous over standard single wall alternatives like PVC:
Single Wall Pipe Types
Common single wall drain pipes include plastic PVC, polyethylene, ABS as well as corrugated steel and aluminum. While cost-effective, these have limitations.
Limitations of Single Wall Pipes
The thinner single layer walls are susceptible to crushing, deforming and losing hydraulic capacity. They resist abrasion, UV exposure and chemicals poorly, shortening functional lifespan.
Side by Side Comparison Testing
Repeated lab tests confirm triple layer HDPE pipes’ superior crush resistance and durability over all types of single wall piping. This supports usage for critical structural drainage roles.
FAQs About Triple Wall Drain Pipes
For further details on effectively leveraging triple wall pipe systems:
Pricing and Availability
Triple wall HDPE drainage pipes sell from $5 – $25 per linear foot based on dimensions. They are available from specialty construction supply retailers.
Sourcing Triple Wall Pipe Supplies
Major manufacturers like Advanced Drainage Systems (ADS) and HOLCIM market triple wall pipes to drainage contractors and municipalities.
Because polyethylene materials are insensitive to chemicals, regular PVC/CPVC solvent cements work to bond triple wall sections and fittings.
Triple wall pipes have one-of-a-kind structural reinforcements and extreme crush resistance. This makes them the ideal drainage solution for the toughest construction challenges.
