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Filling the gap between concrete slabs

BloodyIrishman
Just Starting Out

Filling the gap between concrete slabs

I recently moved into a house with a rather large concreted back yard and want to do something about the weeds that grow between the joints between the slabs. It seems that over the years the ground has settled and the joints between the concrete slabs has become a gap of around 2+ cms  and many CMs deep. The original filler material is a tar sheet material which has degraded and is practically non-existent in some joints. 

Can anybody advise what is the best way fill in these gaps and thereby prevent weeds?

Thanks in advance.

Jason
Community Manager
Community Manager

Re: Filling the gap between concrete slabs

Hi @BloodyIrishman,

 

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Re: Filling the gap between concrete slabs

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This one is probably the biggest of the lot

Re: Filling the gap between concrete slabs

Hi @BloodyIrishman (great name btw) - what you do depends on how many gaps there are to fill, and how much time/money you want to spend.

 

You could use a flexible adhesive/filler such as SikaFlex Pro, which comes in a “sausage” - but it’s about $20 per unit, plus you need a sausage gun. Selley’s also make a similar product “Selley’s Flexiseal” -  Polyurethane Sealant, also in a sausage but about $15.00. These are both 600ml products, you’d have to do some rough math to work out how you need etc. Both of these should last a while, but no product like this is going to be permanent.

 

You could contemplate some sort of grout, which would be a hard filler, so will crack and fail eventually. I have seen this done using an icing piping bag arrangement (I kid you not!) to speed application up.

 

Alternatively, I got rid of my recurring weeds in my pavers in 2 years by applying Roundup - so, a bit of work for a couple of years, but this year - no weeds. Hope this helps, cheers Deb :smile:

Re: Filling the gap between concrete slabs

Following on from @Mathy's point about weed control, you might be interested in the tips on these previous discussions. Something simple like boiling water might be worth a try....

 

 

 

Hope that helps.

 

Jason

 

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