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Green Drain GD4 waterless trap seal for 4-inch floor drains
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GD4

4" Waterless Trap Seal

Fits 4" (DN100) drain outlets. Drop-in install, no tools required.

$49.95

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Pipe Size 4" (99-107mm)
Flow Rate ≥340.00 L/min
Install Time 30 Seconds
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cUPC Listed
ASSE 1072 Compliant
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Inspect the seal around 6 to 12 months in service to confirm the silicone is still intact and sealing properly. Replace only as needed: high-use drains wear sooner, while low-use drains often last a year or longer.

Cutaway view of a 4-inch floor drain and its trap

How it works.

Green Drain is a one-way valve for your floor drain. Water flows down and out. Nothing comes back up.

Inside sits a soft silicone valve. Running water pushes it open; the moment the water stops, it closes and seals tight against sewer gas, odors, and pests. Because it seals with silicone instead of water, it never dries out the way an ordinary trap can, even when the drain goes weeks without use.

It fits 4-inch drains, 99 to 107 mm, and drops in by hand. No tools, no plumber, installed in seconds.

Will it fit? Measure first

Measure the pipe. Not the grate, not the bowl.

Lift the grate. At the bottom of the drain body is a round pipe opening. Measured across its center from inside wall to inside wall, that is the only number that matters. The GD4 seats in a pipe of 99 to 107 mm (4 in.). If the opening is oval, use the smaller reading. Outside that range, another size fits: see all sizes.

Drain in section with the grate highlighted: not the part to measure

Don't measure the grate

The grate is the cover you walk on. It sits on top of the drain body and is wider than the pipe underneath, so its width tells you nothing about fit.

Drain in section with the bowl highlighted: not the part to measure

Don't measure the bowl

The bowl is the basin under the grate that funnels water down. It is wider than the pipe too. The Green Drain does not sit here.

Drain in section with the pipe highlighted: the part to measure

Measure the pipe

At the bottom of the bowl is the round pipe opening. This is where the Green Drain seats, so this is the width to measure. Wipe it clean, then measure inside wall to inside wall.

Floor drain from above with the grate off: a tape across the pipe opening from A to B
Measure A to B. The pipe opening at the bottom of the bowl.

Full installation guide: how to measure, choose a size and install.

Fits these drains
Round floor drain, isometric, with its pipe outlet highlighted
Round
Square floor drain, isometric, with its pipe outlet highlighted
Square
Floor sink, isometric, with its pipe outlet highlighted
Floor sink
Trench drain, isometric, with its pipe outlet highlighted
Trench

Any floor drain whose outlet is a round pipe in the GD4's range. The grate shape does not matter; the pipe under it does. Remove any basket or strainer from the bowl first.

GD4 in section with water flowing down through the open skirt
Water flowing. The silicone skirt opens and water passes.
GD4 in section with the skirt closed and sewer gas held below
Flow stopped. The skirt closes. Air, odor and insects stay below.
The valve, two states

One-way. Opens for water going down, closes when the flow stops. No water to top up, no power, nothing to prime.

Inspect the seal around 6 to 12 months in service and replace only as needed.

Installs in 30 seconds. No tools.

1
Step 1: the grate lifted off a floor drain, shown in section

Lift the grate

Most grates lift straight out by hand. Some are held by one center screw; back it out, then lift.

2
Step 2: measuring the pipe opening at the bottom of the drain, inside wall to inside wall

Measure the opening

Measure the pipe opening at the bottom of the bowl, inside wall to inside wall. The GD4 fits 99 to 107 mm (4 in.).

3
Step 3: the GD4 being pressed down into the pipe opening

Press it in

Push the Green Drain into the pipe by hand until it sits 2 to 4 inches (50 to 100 mm) below the top of the pipe. The silicone gasket creates a snug seal against the pipe walls.

4
Step 4: the grate back in place over the seated GD4

Replace the grate

Put the grate back. Done. Nothing to wire, prime or top up, and a full commercial floor takes an afternoon. Lifts out by hand, or with the extraction tool.

ASSE 1072-2020 Performance Data

Independently tested by IAPMO R&T. These are lab-verified results from an accredited third-party testing laboratory.

≥340 L/min Flow Rate (Level U) No restriction to drainage.
32g Opening Force Opens with approximately 32 grams (1.1 oz) of water.
2,500+ Cycle Endurance Open/close cycles tested and passed.
>96% Evaporation Reduction Maintains trap seal without water.
For Architects & Engineers

Specify Green Drain in your next project.

Download the Revit family set for every Green Drain model, and find us listed in BSD SpecLink and MasterSpec.

Download Revit Families View full specifications →

Technical Specifications

ModelGD4
Pipe Size4" (99-107 mm) / DN100
Height51 mm
Housing Diameter (no gasket)88.39 mm (3.480"), bottom 93.47 mm (3.680")
Housing with Gasket108.56 mm (4.274") wide x 50.7 mm (1.996")
Housing MaterialABS Plastic
Valve MaterialSilicone Rubber
Seal MaterialSilicone Gasket
Flow Rate≥340.00 L/min
ASSE 1072 Opening Force32 grams
ASSE 1072 Cycle Life>2,500 cycles
ASSE 1072 Evaporation Reduction>96%
Pressure Resistance (DTI)>400 Pa
WaterMark LicenseWM-022837 (DN100)
PatentsMultiple US & international patents

Industries we serve.

Green Drain is installed across a wide range of facilities.

Healthcare K-12 Schools Universities Commercial Offices Hotels Restaurants Industrial Food Manufacturing Government Airports Senior Living Data Centers

Certifications and compliance.

Green Drain cUPC certification - IAPMO File 9301 ASSE 1072-2020

cUPC Listed

IAPMO File 9301

ASSE 1072-2020 Standard

Barrier-type trap seal performance standardEvaluated under IAPMO R&T cUPC File No. 9301

Green Drain CE Mark European Technical Assessment ETA-18/0536

CE / ETA-18/0536

European Technical Assessment

Green Drain NSF/ANSI 2 food equipment certification

NSF/ANSI 2

Food Equipment Certified

Green Drain HACCP International food safety certification

HACCP International

Food safety certification

Green Drain WaterMark Australia certification WM-022837

WaterMark Australia

WM-022837 (DN100)

Green Drain California Proposition 65 compliant

Prop 65 Compliant

California compliance declaration

SGS

SGS Aerosol-Retention Test

Test report · retained over 99.9% of an aerosolized MS2 bacteriophage viral surrogate

Green Drain tested by Danish Technological Institute DTI

DTI Tested

Test report · Rapport 957187

Green Drain IAPMO R&T certified plumbing product

IAPMO R&T

Certified Testing Lab

Green Drain VA Godkendelse Danish plumbing approval

VA Godkendelse

Danish Plumbing Approval

View All Certifications

What operators are saying.

"4 months have gone by and I have yet to have a single complaint or concern since the Green Drains were installed."

Winston Andrews, CEO

Pleasanton Unified School District

"Once installed the Green Drain solved our issues. No more need to flush the drains or add enzymes. This product really works!"

Jeff Bowe, Project Manager

Raven Services Corporation (14-story federal complex)

"We have used the following product in all of our bathroom drains, and this has not only eliminated our odor problem, but it has made our internal customers safer."

Mike Malone

FedEx Corporation

For architects and engineers.

The GD4 is the model most commonly written into construction specifications. For CSI-format spec language, ASSE 1072-2020 performance data, and the complete certification matrix, see the Architects and Engineers technical page.

Spec Section 22 13 16
Basis of Design Green Drain GD4, IAPMO File 9301
Patents Multiple US & international patents
View A&E Resources
Technical Drawing
or Spec Sheet Preview
~500x400px

Related products.

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GD3 (3")

 Green Drain GD35 waterless trap seal for 3.5-inch floor drains

GD35 (3.5")

 Green Drain GD5 waterless trap seal for 5-inch floor drains

GD5 (5")

 Green Drain GD6 waterless trap seal for 6-inch industrial drains

GD6 (6")
View All Products

Ready to protect your drains?

Drop-in install. No tools. Works from day one.

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