Are Basement Floor Drains Vented?

Disclosure: We may get commissions for purchases made through links in this post.

Floor drains are designed to efficiently and effectively channel water to sewers or municipal storm drains. They prevent flooding and keep the floors dry. They also provide access points to remove clogs in toilets, showers, and sinks. You may be wondering if basement floor drains are vented. We talked to the experts, and this is what they had to say.

Basement floor drains are vented as this enables them to work efficiently. The vent pipes provide the floor drains with fresh air, which helps the system move water through the drains to the sewer or storm drains.

It is recommended to maintain your basement flood drains to ensure that they will do their job when needed, as this will help keep flooding at bay and avoid expensive water damage. Read on to determine how you can tell whether the basement drain is vented. We will also discuss whether a drain can work without a vent.

Heating grid with ventilation by the floor in hardwood flooring, Are Basement Floor Drains Vented?

How do I know if my basement floor drain is vented?

A basement floor drain is located at the lowest point of the basement. Although the floor drains are rarely used, the drains are critical in preventing flooding, resulting in expensive water damage.

The basement floor drains are vented, which allows them to function effectively. The air from the vents creates atmospheric pressure, which aids the system in moving water through the drains.

The International Plumbing Code specifies that if the distance between the floor drain and the vented line to which it connects is less than 15 feet, no vents will be required for the piping serving these drains.

The basement floor drain might not be vented if it makes gurgling noises as it clears. Additionally, since the vent pipes remove gas and odors, you might experience an awful sewer smell if the drains are not vented. Sewer gases contain methane which can be harmful to your health.

Maintaining the basement floor drain

These simple tips will keep your basement floor drain from being clogged up, thus preventing flooding and extreme water damage.

  • Keep the basement drain clear of any clutter that may block the drain, such as boxes and furniture.
  • Ensure that debris such as leaves and dirt do not wash into the drain by clearing them immediately.
  • Regularly clean any build-up on the drain grate to keep it clean at all times.
  • Run hot water down the drain frequently to dissolve any build-up inside the pipes and create a water seal that blocks sewer gases from trickling up through the drain.

If the basement drain is blocked, read this article to discover "How To Unclog A Basement Drain."

What happens if the plumbing is not well vented?

If the drain lines are vented incorrectly, wastewater and solid waste will not move as required. Additionally, dirt and debris may collect in the vents, causing them to be inefficient. As a result, drains will overflow, toilets and sinks will back up, among other plumbing issues.

Indications that drains are poorly vented

  • Slow drainage - ventilation in the drain pipes allows the natural pressure in the pipes to equalize and help push the wastewater and material along. Therefore, in the absence of proper ventilation, water in bathtub drains or bathroom sinks in the basement will move slowly.
  • Gurgling sounds as the drain clears - restricted airflow makes it difficult for the drain water and waste materials to move through the drain lines.
  • Bubbles in the toilet bowl - the bubbles form as the drain pipes try to get enough air to equalize internal pressure.
  • Sewer odors - the water seal which keeps odors from escaping the drainage system and into the building could dry out if the air pressure from the vent pipes is insufficient, leading to a foul smell in the house.
  • Empty toilet bowl - If the air pressure in the drain lines is inadequate, the water in the bowl can flow away, causing fluctuations in the amount of water in the bowl.

How to clean plumbing vent pipes

Cleaning the vent pipes will restore airflow into the drains, thus ensuring that the drainage system functions correctly. Regularly maintaining the vent pipes will also prevent plumbing issues from occurring.

You will need:

  • A ladder
  • A screwdriver
  • Garden hose
  • Snake or plumbing auger

This set of screwdrivers has comfort-optimized handles for high and low torque applications. Check the set out on Amazon.

Follow these simple steps to clean the plumbing vents.

  1. Use a ladder to climb on the roof of your house. Securely plant the ladder on the ground to avoid falling off. We'd recommend having someone hold the ladder for you while you climb.
  2. Using a screwdriver, unscrew the vent cap and remove it.
  3. Inspect the vent for any obstructions like leaves and debris and remove them.
  4. Spray water into the vent pipe using a garden hose. This will clear any debris that may have accumulated in the vent opening over time. It will also help you identify a significant blockage in the vent pipe if water fills it and backs out of the opening.
  5. In case of a blockage, use a snake to clear it. Insert the head into the vent opening and run the cable until you reach the blockage.
  6. Turn the handle of the snake to work the head through the blockage. The water in the vent pipe will begin to drain as soon as you successfully remove the blockage.
  7. Remove the snake and spray more water into the vent opening.
  8. Observe whether the water comes back up. If it doesn't, you have successfully cleaned the vent pipe.
  9. Replace the vent cap and screw it back in place.

This drain auger has a grip handle and a turning knob that makes it easy to drive the drain cable to unclog the pipes manually. Check it out on Amazon.

Will a drain work without a vent?

It is paramount for any plumbing fixture to have a vent since the vent equalizes pressure in the pipes and prevents a vacuum from forming as the water drains. If the vent pipes are blocked or absent, negative pressure builds up in the drainage pipes, interrupting water flow.

In the absence of traditional venting, you might opt for mechanical venting by using an air admittance valve (AAV), otherwise known as a studor vent. This valve counters negative pressure in the piping system by allowing air to enter the drainage system.

By equalizing pressure in the system, gravity closes the vent terminal preventing sewer gases from infiltrating the building.

If mechanical valves are not installed correctly or at the proper height, they will malfunction, allowing odors into your home. Additionally, you will also encounter frequent clogging in your drainage system. It is advised to ensure that the valves are fixed correctly and above the flood level.

Typically, valves serving a single fixture should be at least four inches above the center of the trap arm. If multiple fixtures are involved, the valves should be at least six inches above the flood level rim of the highest fixture. The valves should be used to vent fixtures on the same floor level.

Because these valves require a level of ventilation to work efficiently, they should be installed in places with sufficient air circulation. Also, they should be easily accessible in case of a blockage.

If the valve malfunctions because it is stuck, you can use a simple spray lubricant to reduce friction and restore it to working order.

You should install the valves vertically since they are dependent on gravity to close once the pressure is equalized.

AAVs do not relieve positive pressure. Therefore, the International Plumbing Code requires at least one venting pipe to extend to the outdoors to relieve the drainage system of positive pressure.

Also, a relief vent should be installed where the parallel divergence is located more than four feeder intervals from the top of the stack.

It is recommended to check with the local authorities before installing a studor vent to confirm that it would be approved for use in your specific situation.

Final Thoughts

Vent pipes ensure that the basement floor drains work correctly. They balance the atmospheric pressure in the pipes, keeping the wastewater flowing while keeping odor and gases away from your home. You should regularly maintain vent pipes to avoid blockages that may cause them to malfunction.

Check out these topics as well:

Basement Sink Backing Up – What To Do?

Can I Drain Basement Dehumidifier To Sump Pump [And How To]

Leave a Reply