The heavy rain is here. A leaking garage is the last thing you need.

So how do you get down to fixing the problem? Is the leak preventable?

Dive in and read the guidance below to find out how to keep those leaks at bay and carry out the right garage roof repairs!

Table of contents

How do I stop water leaking into my garage?

To prevent a garage from leaking water, you must first identify where the leak is coming from. Once you have done that, you can move forward with securing the garage.

The most important thing to note is that a garage does need regular maintenance. The door, floor, walls and roof, all require an inspection from time to time to help keep an eye on any upcoming damage and fix it as soon as possible to keep those leaks from taking place; even if suitable waterproofing materials are in place.

Some repairs will last longer than others, but you may find a solution that works longer than expected. This will depend on the quality of the repair and whether the initial damage is severe.

Better yet, move anything valuable or electrical out of the area before making repairs. This can reduce the damage to your items and the danger to yourself.

Looking for the damage in a leaking garage roof

For a leaking garage roof, identify which part of the roof is causing the leak as soon as possible.

You can identify the source of the leak via the following areas:

  • The garage ceiling where the roof panels sit.
  • Garage roof corners.
  • The connection where the roof and the property connect.
  • The guttering or drainage.

If there is discolouration on any wood or concrete walls, this can also be a sign the roof is causing a leak. This could be damaged roofing materials like sheets or tiles, but can also be the flashing where the roof and the walls connect.

Make a note of any issues. If the damage is too excessive, contact a professional to replace the roof as soon as possible. If you’re a seasoned DIYer and want to provide a temporary fix, here’s how to stop a leaking garage roof.

How to stop a leaking garage roof

There are multiple ways to prevent the garage roof from leaking once you’ve found the issue. You will need to ensure that it is a dry day as this can make repairs easier.


If your garage has a flat roof, check out the flat roof buyer’s guide to find out more about waterproofing and the correct leaking garage roof repair procedure.

Leaking garage door

The door is one of the easiest ways for water to get into the garage. Identify where the water is coming through before choosing preventative measures.


  • Door leaks commonly happen because the edges of a door are not properly sealed.
  • Spaces in the door itself (including damaged areas) can risk leaks appearing.

How to stop rain from coming in under the door

Whether under, over or around, guarantee your garage door stops allowing water to seep through the damaged or non-waterproof spaces. Here’s how to fix a leaking garage door.


  • Seal the garage door with new weatherstrips to ensure no little spaces allow the water to slide through the bottom, top or sides of the door; if the garage door is beyond repair, replace it as soon as possible.

Garage leaking at floor level

When the garage is leaking at floor level, this could be a sign of one or multiple issues.

Possible issues:

  • Your floor has cracks or holes (some of which can’t be seen by the naked eye).
  • Condensation that typically occurs when warm air reacts with cool concrete, which results in vapour settling on the surface and turning into water.

Find out more about condensation via our “Damp proofing buyer’s guide” if you have issues across the property.

How to stop a garage floor from leaking

You’ve found the problem, so what’s the solution? Here’s how to carry out garage floor repairs and fix a leaking garage floor.


  • Clean the cracks and fill them with a waterproof concrete compound to patch up the damage (if the damage is excessive, replace the floor).
  • Clean any holes and steal the entire garage floor with a silicate-based solution – do not regularly use floor paints that provide a moisture barrier.
  • Placing a dehumidifier in the garage during warmer temperatures to reduce the risk of condensation occurring; check the tank of the machine and empty it whenever it’s full as mould can form in the tank if not cleaned.

Water leaking into the garage when it rains

Sometimes even with protective measures water can make its way into the garage because of outside factors. With heavier rainfall, you may have to look to the exterior to make changes. The landscape itself might not be doing you any favours.


  • The level that the garden or driveway is on might be one of the main factors causing water to leak into your garage if you have elevated ground sloping towards the garage, the rain is being guided towards the door and voila! You’ve got a flooded floor space in the garage.

How to stop water leaking under the garage door

So how do you stop water from leaking into your garage? Well, here are some ways you can prevent the issue.


  • Adjust the level of your current landscape or driveway to stop it from sloping towards the garage and letting water seep through the door.
  • Install a French drain (also known as a channel drain) to direct water away from the garage.
  • Sometimes water can seep through cracks or holes in the driveway, so you will need to repair this with cement (if the damage is extreme, replace the driveway).

You can find out more about garden drainage if you need efficient ways to reduce water build-up in our guide on “How to improve garden drainage”.

For information about channel drainage, its uses and how to install it, look to our channel drainage guides for help and advice.

Why do garage leaks happen?

A garage is not waterproof. So, you must take action to prevent leaks from occurring as soon as possible.

How do they start to occur in the first place? Is it just the heavy rain?

Nope! Here’s a summary of how leaks can develop.


Vermin (rats, insects, etc.) can damage the materials in the garage; this allows water to escape through to the interior.

  • Doors not being waterproof allowing it to rush through the edges.
  • Poor drainage just outside the garage door.
  • Blocked or damaged gutters (find out more about “What damage a leaking gutter can cause”).
  • The landscape slopes towards the garage.
  • Cracks or holes in the walls or floors.
  • Poor roofing due to damaged materials or wrong installation.
  • Damaged or poorly installed flashing between the roof and the wall of the property.
  • Poorly sealed joint seams where products are attached to a wall (doors, windows, utility boxes etc) allow water to enter through said seams.
  • Old and damaged weather strips don’t perform correctly.
  • Condensation.

Can I repair an asbestos garage roof leaking?

You should not deal with asbestos unless you’re a trained professional. The reason is that any damaged asbestos roofing space is likely to release fibres and, if inhaled, can cause respiratory damage. So, if your garage roof is damaged and you’ve got a leak you can’t ignore, it’s best to contact a trained expert.

The substance can be found in many older roofs (not just garage roofs). Find out more about asbestos via our roofing sheets buyer’s guide.

In conclusion, don’t let those garage leaks affect your storage space in the garage. Find the problem, look at the solutions and get to fixing or contacting your professional repair service as soon as possible to keep your garage from leaking.

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