Sump Pump Weep Hole Guide – Location & Installation

Do you have any plans to fix a sump pump weep hole but have no idea where to start? “What even is a sump pump weep hole?” you may ask, “Where and how do I install a weep hole?”

To answer your questions, a basement sump pump is that heavy device that helps your water move from the underneath of your home to the outside. And a weep hole is what a sump pump significantly requires to function at its best.

sump pump weep hole

Without a weep hole, or ‘relief hole’, being bored into your sump pump, an airlock would occur. An airlock coming into the picture would lead to your basement getting flooded and, subsequently, high costs to pay for repairs.
This article will discuss how to avoid these unnecessary and costly occasions and help you learn about sump pumps. We will provide you with a sump pump weep hole installation guide to help you fight against airlock.

Concept of Sump Pump

Now that you’re a little educated about what a sump pump weep hole is let’s dive in deeper. A sump pump is a device that’s governed by fundamental physics. This water-cooled machinery is accommodated by (if constructed properly) a case that is made from materials like stainless steel or cast iron. At the bottom of the pump, the motor device drives a spinning propeller and forces water up the pipe system.

To make it easier for you to imagine, you can take, for example, an airplane with its propeller pointing at the ground’s surface, and the air is thrust upwards. This concept is how the water in your basement makes its way to the exterior sump pump.

The water is thrust upwards through a PVC (Polyvinyl Chloride) pipe that’s about 1.5 or 2 inches. It passes through a one-way control valve and runs into your backyard or a drainage system. The fundamental idea is that, so long as the basement sump pump maintains the drainage of water in the basin, it can regulate the level of water beneath the ground and help your basement floor avoid dampness and moisture.

Sump Pump Weep Hole

A weep hole is like a corridor that allows water to pass through to the exterior of a building. Your home requires a weep hole to stop water from entering the inside. As you will see, weep holes can be utilized in several places, such as on windows or bricks.

Some would say that just as the gills of a fish and the lungs of a human, weep holes play a crucial role in a house’s life as they allow it to “breathe.” Weep holes allow water to depart from the house because there are several ways for water to penetrate the house.

Sump Pump Weep Hole Guide

sump pump weep hole

Sump pump weep hole installation can seem complicated, but it is simpler than it looks. The relief hole may have been drilled beforehand, in case you hired competent and professional installation help to help excavate and the system installation, but it’s always best to double-check.

In this Weep Hole Installation Guide, we will discuss how a weep hole is simple and easy to drill with the correct tools. There are various tools to use for drilling; you just need to remember to use them at a normal speed. Taking the time and ensuring the drilling surface is flat will help ease the job.

How to Prepare to Drill a Weep Hole

Before you decide to drill a hole, there are safety measures and steps you must consider taking to prevent any damage to the sump pump. These steps make it easier and safer for you when drilling a weep hole:

  1. Cut off the power supply.
  2. Examine the size of the outlet.
  3. Extension cords must never be used.
  4. Have a different circuit for use.
  5. Labels and tags should not be removed.
  6. Never allow the pump to run dry.

Procedure Guide for Sump Pump Weep Hole

Now that you have learned about weep holes, you know what to do to prepare for drilling one. So, let’s dive right into the installation process. What actions do you need to carry out when installing a Sump Pump Weep Hole? Let’s dive right into the Weep Hole Installation Guide:

  1. First, remove your pump from the pit and unplug it from the drainage lines.
  2. Search for a power drill with a drill bit that’s 3/16 inches.
  3. Between the line of discharge and the check valve, you must drill a 3/16″ hole downwards at an angle of 45 degrees.
  4. Install your pump and reconnect it to the power cable and drain lines.
  5. Have your basin filled with a couple of buckets of water and test out your fixed basement sump pump and weep hole.

What Is an Air Lock?

When bubbles of air are caught by the water running through the pipe, it creates an ‘Air Lock’ that hinders water from flowing smoothly. Additionally, airlocks typically impact hot water pipes since cold water pipes experience less force as compared to hot water pipes.

In a well-constructed and low-pressure pipe system for water, air must be cleared spontaneously and naturally, even if the water runs out. The air should automatically float to the surface and be naturally thrust out of the pipe system as it fills up. When the water pipe system is poorly built, that leaves room for the airlock to occur.

The phenomenon of an air lock occurs owing to the limitation in the flow of liquid or a complete halt brought on by vapor entrapped in the peak place of a liquid-filled network of pipes. The air then travels to any prominently high position because it has a lower density than water.

Benefits of Sump Pump Weep Hole

To stop airlock, sump pump weep holes are punched into the drain pipe. An airlock can be avoided within the impeller chamber; weep holes, or relief homes, are essential in sump pumps. To prevent any difficulties for the sump pump in efficiently removing water from the house, weep holes are needed.

sump pump weep hole

Preventing Air Lock with Weep Holes

Airlocks are harmful to your basement sump pump, so there must be ways to prevent them. Here are the number of ways you can avoid airlocks:

  1. Limiting the ability of air to enter the pipe and cause problems.
  2. Ensure that there are no high areas where pockets of air can collect while also ensuring that the pipeline is rising and dropping steadily or with a level flow.
  3. Guarantee that the water velocity in the pipe system is sufficient enough to carry all the air bubbles towards the terminus of the pipe.

The phrase “weep hole” may be amusing to some, but it serves as the best defense against a sump pump with airlocks. When it comes to sump pumps, weep holes help in limiting the entrance of air to go through.
To address any issue with sump pumps, drilling a vent hole goes a long way. You can dig a little 3/16 inch hole on the side of the outlet pipe inside of the sump hole. It’s always a great decision to personally inspect the pipe system so that you can ensure the hole is neither blocked nor jammed.

While some versions produced by reputable brands have predrilled the weep holes required, other models need you to bore a sump pump weep hole on your own when you fit the pump.

You may think it sounds ridiculous to drill a hole into your newly bought sump pump and even see it as a straightforward way to spoil your new device. However, if you consult the owner’s manual, many types advise you to drill a sump pump weep hole directly overhead the watermark.

Where should I drill a sump pump weep hole?

So now that you know the importance of a sump pump weep hole, you need to know where precisely you should drill one. Begin the process by making a hole into the outlet pipe with a tool. The primary pump must be several inches above the site of the drilling.

The ideal location to bore a weep hole is between the control valve and the drainage lines. The hole must be bored while pointed downwards at an angle of 45 degrees. Drilling at an angle of 45-degrees is the best option because it increases the likelihood that the weep hole will flow downward and toward the basin’s bottom.

The 45-degree angle occasionally aids in sound elimination. The hole must be positioned inside the sump pit but away from the pump. You have to ensure that the sump pump is unplugged from the line before you start working on it so that the whole procedure is simplified.

In doing so, you may be assured that water won’t be blasted onto the pit, upward, or towards the sides. You may find that the water begins to spew whenever the motor operates. However, this is entirely natural.

The important thing is that the sump pump weep hole will let any air that becomes captured between both the impeller and control valve exit together with a bit of water. Now that the pump has been emptied, you can anticipate flawless operation of the sump pump and the appearance of water.

Why do Sump Pumps Need Weep Holes?

As we have discussed previously, what air locks are, how you can prevent them, and where you can drill the holes to prevent air locks, we finally reach the topic of the benefits of sump pump weep holes. Why exactly do sump pumps require to weep holes?

The purpose of the weep hole is to avoid air lock. This typically occurs whenever a significant volume of water comes into the basin. When the pump begins to operate, the water ultimately begins to build up on the motor, and air bubbles become confined within.

Normally, the additional air finds its way through the outlet pipe in between the point of discharge and the control valve, which is what usually occurs. However, it will potentially remain there if you accidentally make the air become imprisoned there, and there isn’t any way for it to evacuate out via a weep hole.

Without such an opening like the sump pump weep hole, the motor may well become empty and dry and eventually burn out. This can be prevented by constantly monitoring the water level in the pump. You must add water if it’s lacking. Using a water hose, you can do this through the weep hole in the submersible pump.

Even though you can find your sump pump running and working correctly, you should not anticipate any release from the drain line. As you will observe, no liquid will flow out of that end. This can occasionally feel a little overwhelming.

Remember that this might cause flooding everywhere and cause the water level inside the pump to rise persistently. If your motor is ever humming, but nothing is flowing out of the pump outlet, there is probably an airlock.

And for this reason, we believe adding a weep hole to a sump pump is beneficial. You’ll need to create a weep hole to accomplish this project. Furthermore, the weep hole also extends the lifespan of the sump pump.


Why do sump pumps require to weep holes?

Sump pump weep holes are an essential device that helps prevent air locks in the impeller area. These relief holes are significant owing to the permission of air to escape from the pump’s chamber. This helps in avoiding the prevention of the beginning of subsequent cycles.

Where should a sump pump’s weep hole be located?

A weep hole can be characterized as a relief hole that keeps pumps from experiencing an ‘airlock’. To prevent the pump from not transferring water when operating, a weep hole of 3/16″ is needed. It must be drilled downward at an angle of 45 degrees between the check valve and pump discharge into the discharge pipe underneath your floors.

How much should be the weep hole size?

A sump pump weep hole must have a diameter of 3/16 inches or 4.8mm, not less than that. At least 2 weep holes must be present in each vent opening and be spaced 450 mm apart.

Is a sump pump weep hole necessary?

The best sump pump models are built without any weep holes. However, in the hope of avoiding an airlock, most widely used models require a weep hole.