My Garage Is Flooding: 5 Common Scenarios and Ways to FIX Them!

Does your garage keep flooding and you’re unsure how to fix it? Not to worry, have a read of the below article which will first help you identify the cause of the flood and secondly provide recommendations on how to fix it.

A flooding garage

The first step you want to take is to identify the cause of the flood in your garage.  Below are a number of things to check:

Scenario 1: Garage floor floods from the rain

Within Australia, the most common cause of flooding in your garage is from excess rain flowing down towards your garage and entering the perimeters of the garage, usually under the garage door or secondary doors entering the garage.

If this is your issue, then the best way to fix this is to ensure there is ample drainage installed around your garage perimeter to capture and disperse the rain before it enters your garage.

The fix if flooding is from excess rainwater

The most common way to fix this is to install a channel drain in front of your garage door or other entryways to your garage.

Why a channel drain?  These are the perfect solution as they are flat to the ground, non-intrusive drains that capture any excess rainwater flowing down towards or has built up around your garage entrances.

Once the water is captured you can then direct this drain off into your property’s drainage system such as your soakwells.

It’s important that when installing a channel drain in front of a garage or door, ensure the drain is wider than the width of your door to ensure that rainwater flowing from different angles is captured.

See also: How to install a channel drain

Scenario 2: Garage roof leaks when it rains

If the water isn’t coming in around the entrance of your garage door (or any other entrances) then water could be coming in from a leak in your roof.  

If you have a tiled roof, the water may enter through a broken ridge cap, a gap between tiles, or potentially around the roof flashings.  

Alternatively, if it’s a metal(colorbond) roof then it could be coming in around the ridges, in between metal sheets, or around the roof flashings.

The fix for a leaking garage roof

If the leak appears to be from your roof into your garage then if you’re the handy type and you’re comfortable working at heights then you could take the following steps:

  • When it’s raining use a torch to shine up onto the underneath of the roof to see if you’re able to identify where the leak is. If your garage has a ceiling, roof sarking, or insulation then this may not be possible.
  • Once you have a good idea of where you think the leak is coming from after the rain has stopped and the roof is dry you can then proceed to safely get up onto the roof and make the necessary repairs.

See also: Why is my metal roof leaking?

Note, if you’re not comfortable making such repairs then please contact a professional roof plumber in your area.

Scenario 3: My garage floor floods when it’s not raining

If your garage floor floods and there is no rain then this could be one of three things, that being that you have water leaking from your garage ceiling, from within the cavity of the surrounding walls, or up through the floor of your garage.

If you have water leaking down from your garage ceiling or through the walls it’s likely to be some type of plumbing pipe where the pipe has sprung a leak or has cracked allowing water to flow from the pipes and into the roof space over your garage.

Alternatively, if water is coming up through the garage floor then this could also be a plumbing or sewerage issue where water is leaking under your garage floor and seeping up through cracks in your floor into your garage space.

How to fix potential plumbing or sewerage leaks

If you believe you have a plumbing or sewerage leak such as the above then the recommendation is to call out a professional plumber to inspect the garage area to identify and fix the problem.

Scenario 4: Water is seeping through my garage walls

Water coming through garage wall
Example of water seeping through garage wall

Are you’re garage waIls discoloured, damp, or have water seeping through them?  If so this is a common issue that can lead to flooding of garages and usually relates to the out walls having inadequate waterproofing or sealing on the external wall to prevent water from coming through.

How to fix seeping garage walls

If this is your issue then you first need to inspect your outer wall to see how moisture is building up and seeping through.  Usually, this occurs when the inside of the garage is lower than the outside and where the garage wall is retaining dirt.

If this is the case then your best bet is to:

  1. Dig away the soil against the wall;
  2. Hose down and let the wall dry thoroughly;
  3. Once dried, fill any cracks and apply a waterproofing rubber membrane/sealant onto the wall;
  4. Usually, after this, I also like to roll out some waterproofing plastic sheeting along the wall just as an additional layer before backfilling the soil.

Scenario 5: My garage door is leaking

Unfortunately, in some cases, rainwater can enter through the gaps of your garage door, either down the side of the door or between the horizontal sections of your door.

How to stop your garage door from leaking

If this is the issue then your best bet is to inspect the joins of the door to identify where the water is leaking through.  From here you can then look at applying a type of weather stripping seal to the outside of the join to stop the water from getting through.

Unfortunately, if this doesn’t resolve the issue then you may like to consider looking at a replacement door or getting a professional garage door installer out to discuss it further.

Note, if water is building up at the bottom of the garage door then as I mentioned above, consider installing a channel drain along the front of the garage.

Final thoughts

I hope you found this article helpful, and as always, if I’ve missed something or you think there is something else I need to include please let me know using the link below and I’ll get to it.

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