1-1/2 inch x 1-1/4 inch PVC DWV Trap Reducing Adapter Plastic x Slip Joint

1-1/2 inch x 1-1/4 inch PVC DWV Trap Reducing Adapter – For Gravity Drainage Transitions

The 1-1/2 inch x 1-1/4 inch PVC DWV Trap Reducing Adapter is designed for use in non-pressurized drain, waste, and vent (DWV) systems to connect differing pipe diameters at fixture tailpieces or trap inlets. This fitting enables code-compliant transitions where 1-1/2 inch DWV lines must connect to 1-1/4 inch waste arms or trap outlets in plumbing systems.

Application-Specific Design

This trap adapter is molded from Type I, Grade 1 polyvinyl chloride (PVC), and manufactured to conform with ASTM D2665 dimensional and material specifications. It provides a slip-joint connection with integrated reducer, supporting proper slope and flow velocity for downstream drainage. Advantages include:

• ✅ Solvent Weld Compatibility – Smooth socket ends designed for permanent bonding with PVC solvent cement and primer.
• ✅ DWV System Integration – Allows transition between fixture tailpieces and main waste lines with minimal flow disruption.
• ✅ Non-Corrosive Construction – Resistant to common household chemicals, wastewater, and cleaning agents.
• ✅ Uniform Wall Thickness – Engineered to maintain structural stability across thermal and mechanical loading conditions.
• ✅ Third-Party Certification – Complies with NSF 14 and UPC requirements for DWV fittings.

Installation Overview

Install using standard PVC joining practices per ASTM D2855. Ensure all mating surfaces are clean and square. Apply primer and cement in accordance with local code and manufacturer recommendations. Dry-fit prior to final assembly to verify alignment. This component is intended for gravity flow systems and should not be used in pressurized applications.

Specifications

• Material: PVC (ASTM D2665)
• Size: 1-1/2 inch x 1-1/4 inch
• Connection Type: Slip joint x slip or slip x hub (varies by model)
• System Type: DWV only – non-pressurized
• Certification: NSF 14, UPC listed for DWV use

Use Cases

This adapter is used where a fixture or branch waste arm of 1-1/4 inch nominal size must be integrated into a 1-1/2 inch DWV branch. Common installations include bathroom lavatories, bar sinks, and tailpiece-to-trap transitions in residential and light commercial systems. It supports compliance with IPC and UPC slope and sizing tables when properly installed.

Material Performance Note

PVC is selected for DWV applications due to its lightweight handling, dimensional stability, and resistance to microbial and chemical degradation in domestic wastewater environments. It offers a long service life under standard plumbing conditions when supported and installed to code.

Manufacturing Standards

This reducing adapter is injection-molded under controlled tolerances to ensure concentricity and sealing integrity across production batches. All fittings undergo dimensional and burst testing as part of QA processes consistent with ANSI/NSF and CSA plumbing standards.