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How to add a water barrier for garage?

saleens281
Finding My Feet

How to add a water barrier for garage?

Hi team,

 

My garage is in a downward slope, below the ground level. the water from the foundation is seeping through the cove joint into the garage. 

 

what waterproofing sheet can i use to create a barrier to prevent water seeping through? can i use this product? 

 

https://www.bunnings.com.au/cagroup-2-x-50m-200um-medium-impact-polypro-builders-film_p0334738

 

thanks

Steve

MitchellMc
Bunnings Team Member
Bunnings Team Member

Re: water barrier

Welcome to the Bunnings Workshop community @saleens281. It's terrific to have you join us, and many thanks for your question about preventing water seepage.

Where were you intending to place this sheeting, on the inside or outside? I can't imagine sheeting will prevent this issue from occurring. Perhaps posting some images of the area so our helpful members can see what you're working with will assist. Let me know if you need a hand uploading some photos.

 

Water penetration is best resolved by waterproofing the exterior side of the wall, preventing the water from entering the wall in the first place. I understand access might not be possible due to the slope. If it is, drainage should be installed to take the water away and stop it from building up against the rear of the wall. You can also waterproof the back of the wall as a secondary measure.

 

What material is the wall constructed from? If it is masonry, you could remove any coatings on the wall and apply Dunlop 4L Damp-Proof Waterproofing. It resists hydrostatic pressure, which is water in the wall trying to push it off. Waterproofing the inside of the wall is a last-ditch effort as it traps the water within the wall and doesn't resolve the issue. The water will then travel along the wall and try to find another escape route.

 

Before applying the waterproofer, it would be an idea to seal any gap between the floor and wall with Sikaflex 11FC.

Please let me know if you have any questions.

Mitchell
 

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Re: water barrier

thanks Mitchell. this is not the best photo but the house is on a slight slope and the garage level is about 10cm lower than outside. i think when it rains the water from the soil is seeping through between the wall and the floor. as you can see the access is not easy. however the concrete outside the garage is about 1m long so i was looking to put a plastic barrier along it. please let me know what you think along with any other Solutions. thanks!

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Re: water barrier

I'd suggest coating the trough drain and the first couple of courses of bricks with Dunlop 4L Damp-Proof Waterproofing, @saleens281. You can then coat the inside of the garage wall from the door sill downwards. Between the bricks and the floor inside, run a bead of Sikaflex 11FC to seal any gaps.

 

Is there any chance this moisture is simply coming in under the door? If so, a door seal can be installed to prevent that issue.

 

Mitchell

 

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