Can You Build a Garage Over a Septic Field?

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Undoubtedly, it’s a great idea to build a garage in your house. It adds value to your home and allows you to use more space for storage purposes. But while building a garage, you’ll have to select the construction area wisely.

If you’ve been wondering whether you can build a garage over a septic field and scouring the web looking for the answer to “can you build a garage over a septic field”, you are headed for a disappointment.

can you build a garage over a septic field

Answered Once & For All: Can You Build a Garage Over a Septic Field 

When you construct a garage over your septic field, it becomes almost impossible to do necessary septic maintenance or drain the septic tank.

Besides, when you put heavy vehicles over the septic field, it can damage the whole system. Because of all these reasons, almost all the local ordinances prohibit homeowners to build any structure, especially a garage over a septic field.

Septic Field

Septic systems and septic fields are used interchangeably, which means the underground wastewater treatment facilities. Usually, a septic field consists of a soil absorption field, a tank, and a drain field.

All these parts of the septic field function together and treat the wastewater. After preparation and treatment, a septic field or septic system distributes the water back to the sewage canal. 

You may be thinking about why you should worry about a septic field when it’s just treating and distributing the wastewater.

If the septic field of your house doesn’t function well, you’ll have various plumbing issues, which will lead to heavy repairs. Besides, when you have a malfunctioning septic system, your house will become unlivable too.

How Much Weight a Septic Field or Septic Tank Can Hold? 

A septic field or septic tank isn’t built to withstand heavy loads. There is no specific weight limit for septic fields, but most professionals suggest not to put any heavy machines or vehicles on the septic field.

Even sometimes, low-weight vehicles like golf carts, ATVs, and mini coopers can cause damage to the septic field or septic tank. 

Considering all these facts, you should never build a garage on top of a septic field. Besides, while parking your car or putting other machinery, you’ll have to ensure that it isn’t on the septic field.

If you repeatedly put heavyweights on the septic field, it can damage the structure of the septic field and cause various plumbing issues.

The Boundary of a Septic Field 

Now that you know why you shouldn’t build a garage over a septic field, you should know where the septic system or field boundary ends.

Without knowing the boundary of a septic field, you might accidentally end up building a garage over a septic field and causing damage to the septic system. 

How to Identify the Septic Field Boundary

  • To find the septic field boundary, you’ll have to look at the blueprint of your house. From the blueprints, you’ll be able to determine where your septic field starts and ends. 
  • If you can’t determine the boundary of your septic field, you’ll have to find the drain lines of your plumbing system that is connecting your house and the septic tank. Generally, the septic tank is built about 10 to 15 feet away from your house exterior. 
  • Apart from these, to find the leach field, you can check your land slope. However, while checking the land slope, don’t use heavy machinery. Otherwise, you’ll cause damage to the utility lines and septic tank. It’s recommended that you consult an electrician or gas provider before digging holes to find the septic field. 
  • Also, you can use a long and thin stick, known as a septic field probe, while determine the septic field boundary. With this probe, you’ll be able to find the edges of the septic tank without digging deep.

Frequently Asked Questions about Building Garage & Septic Field 

1. What Can I Put On My Septic System? 

A septic field isn’t built to u003cstrongu003eu003ca href=u0022 target=u0022_blanku0022 rel=u0022noopeneru0022u003ebear heavy loadsu003c/au003eu003c/strongu003e. You can put herbaceous plants and grass on the septic field. But don’t park any vehicle or heavy machinery over the septic system or septic field.

2. What is the lifespan of a Septic Field? 

u003cstrongu003eUsually, a septic field lasts for about 15 to 20 yearsu003c/strongu003e. However, if the septic field is well maintained, it can last more than 40 years. 

3. How Far Should I Build My Septic Field from the House? 

The distance of the septic field varies. u003cstrongu003eBut it’s recommended that you build your septic field at least 10 feet away from your house. u003c/strongu003e

4. Can I Put a Fire Pit On a Septic System? 

If you put the fire pit directly on the septic field, it can melt the drain pipes of the system. u003cstrongu003eThat’s why it’s better to keep the fire pit away from the septic field.u003c/strongu003e


The bottom line is that you should never build a garage over a septic field. Also, while parking your cars, you should maintain a distance from the septic field.

Hi, I am Brent Hartman. I am a DIY enthusiast and love to improve and organize the garage in the most innovative way. I created this website out of my passion for helping people organize their garages.

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