A gully trap is a significant part of the plumbing system. It is an extension of the drainage pipe in the form of a basin that allows water to safely pass through the sewage system without letting dangerous gases escape. It retains a body of water, which works as a water seal. Other than that, a gully trap also stops insects and vermin from escaping and spreading diseases.
A gully trap chamber should be self-cleaning and it should create adequate velocity from the flow of the water that makes them self-cleaning. A gully trap is placed outside the house or a building before it is connected to the external sewer line. It also collects waste water from wash basins, kitchen sink, bathrooms, and wash area.
Is a Gully Trap Important?
Yes, gully traps are important for a house or a building (both commercial and residential). It prevents dangerous gases that form through stagnant or wastewater from escaping. Also, it works like a barrier, which keeps cockroaches and rats from entering the house. It is also an effective tool to get rid of surface or rainwater.
Gully Trap Size
The depth of the water seal in a gully trap should be a minimum of 50 mm. Also, its total depth should be less than 30 cm and the water depth should be less than 15 mm. It is also important that all gully traps have a cast iron grating 15 cm x 15 cm and it must be fixed in a concrete foundation and installed in a brick masonry chamber. The chamber also has to be air and water-tight. A gully trap must be cleaned at frequent intervals to stop it from choking.
Difference Between a Drain and a Gully Trap?
The difference between a drain and a gully trap’s functions is that a trap works as a barrier to connect the drainage system to your home and protection against pests and toxins. A drainage system simply moves out the wastewater from your home.
A drainage system is dependent on a good plumbing gully trap to efficiently remove waste water and rainwater from an underground drainage system. With a good PVC gully trap, a drainage system can remove rainwater from paved areas as well.
P-Traps and Bottle Gully’s
There are two types of gullies: p-trap gullies and bottle gullies. Both of these types of gullies work differently but achieve the same goal. By using a 110mm drainage pipe that is connected to a hopper, the drainage pipe collects the wastewater into a small basket of water at the bottom of a p-trap and then removes the waste into the outlet pipe. One of the disadvantages of the p-trap gullies is that debris gets collected at the bottom, which can cause a blockage.
This is why bottle gillies are the preferred choice. If there’s a blockage in a p-trap, you have to call in the drainage expert to remove the blockage. Also, it is difficult to clean these types of blockages.
Functions of a Bottle Gully
A bottle plumbing gully trap works the same way as the p-trap, but it doesn’t have a removable hopper and bottle gully traps are roddable. It is better than a p-trap because it doesn’t collect water in a bucket first. Instead, they have a sleeve inside the lining of a gully that gushes the water into the sewage system. There’s still water present inside the bottle gully, but they are designed for easier cleaning in case a blockage happens
Back Inlet Gully Trap and Its Functions
A back inlet gully trap chamber has all the benefits of a normal bottle gully trap but has the added benefit of removing rainwater in large quantities. After rainwater goes into the hopper, it can sometimes cause blockage because in a regular bottle gully trap the inlet pipe is lower than the outlet pipe. A Back inlet trap addresses this problem. This trap is highly recommended if a large amount of surface water is accumulated and causes frequent flooding.
How to Clean a Gully Trap?
We’ve already established that a gully trap functions by connecting the drainage pipe to the sewer system. However, sometimes the traps get blocked. If you have a p-trap then it is difficult to clean this trap because of the curvature pipe that doesn’t give access to the rest of the pipe. It takes specialised equipment to clean a p-trap gully completely and flush it out. DIY plumbing and cleaning tricks won’t do the work here.
Bottle gullies are easier to clean as you can remove the inner sleeve and clean the gathered debris, which is causing the blockage.
One of the best ways to clear blocked drains is “Drain jetting.” The flexible jetting hose can enter spaces with less access and tight spaces and the pressure from the hose does all the cleaning. Also, it takes experience to handle a jetting hose. So, always consult a drainage professional to clean out your gully traps.
Final Thoughts
Gully traps are important for a drainage system whether it is a house or a building. It keeps dangerous gases, pests, and rodents away from the house. If not installed properly, it can create an uncomfortable atmosphere in the residential area. We hope this guide will help you better understand gully trap functions.
