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Do Garage Floors Have to Slope?

Do Garage Floors Have to Slope

Do garage floors have to slope? The short answer is yes. The slope allows water and other liquids like oil to drain out of the garage instead of standing on the floor. 

You may be concerned about the angles and dimensions of your garage floor if liquid does not drain out, or if it seeps into the garage.

Maybe you are attempting to build a new garage yourself, or you want to know enough about the slope of the floor to verify the knowledge of your contractor.

In any case, garage floors have to slope.

The slope of your garage floor is important for proper drainage.

Keep reading to discover everything you need to know about the slope of garage floors. 

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How Should a Garage Floor Slope? 

There are a few factors that determine how a garage floor should slope, and these tend to vary depending on the conditions of where you live.

Here are three main factors that will affect how your garage floor should slope. 

The Usual Math 

Typically, the angle of the garage floor slope is not severe.

A garage floor slope is almost always subtle enough that it can barely be seen.

Should you wish to check the current angle of the slope yourself, be sure to use a string level and a protractor.

According to some expert contractors who pour concrete for garages, one-fourth of an inch per foot is the math they generally follow.

In some cases, you can even get away with three-sixteenths of an inch per foot, but you must be willing to precisely level each layer of concrete (you may notice this process being referred to as a “screed” elsewhere) and carefully finish the job.

However, a slightly larger slope may be necessary if you live in an area that receives a lot of snow or precipitation. This math may also differ slightly according to where you want the slope to direct drainage. 

Where to Drain 

Where the garage floor drains and how the floor tends to slope primarily depends on the climate wherever you are located.

In places where water can reach its freezing point, thirty-two degrees Fahrenheit or less, having drainage go towards the overhead door can be a problem.

Any seeping water may continue to freeze and melt in your driveway, which will probably warp it. 

Other drainage options for the slope of your garage floor include angling the slope towards the center of the garage and directing drainage into a dry well or into a drain that leads outside.

Building Codes to Follow 

Be sure to check local and state building codes before you determine which way you want your garage floor to slope and where you want it to drain.

While they may feel restricting, these codes should account for the elements and allow for whatever type of slope is the most optimal for your garage.

For example, some areas do not permit the installation of an exterior drain because the elevation is too low for this method of drainage to be effective.

However, if your area at least allows for the implementation of a dry well, you can still have your garage floor sloping towards the center. 

Who to Consult About the Slope of Your Garage Floor 

If you are concerned about the current slope of your garage floor, or if you are thinking about sloping and pouring a new garage floor and want to ensure that it is done properly, contact a company or independent contractor who specializes in pouring concrete floors.

Be sure to look for an expert in your area.

Reputable companies will have credible certifications, while trustworthy independent contractors will have a good portfolio that showcases their skills. Both will probably have positive testimonials from other clients on their social media. 

Important Information to Take Away 

All garage floors should have a slope. If yours does not, you ought to be concerned, as this means your garage cannot drain liquids properly.

The slope of a garage floor can easily be measured with a string level.

When constructing a new garage floor, the slope should usually be about one quarter of an inch per foot, although this math can vary depending on how well the concrete is leveled and which direction the slope is going.

Be sure to consider the climate and building codes where you live before deciding how to slope and drain your garage floor.

If you feel uneasy about doing this work yourself, consult an expert company or independent contractor.