Crumbling concrete between patio paving allowing weeds to grow

Busterthedog

I have a small patio with paving slabs,the concrete inbetween the slabs has crumbled and weeds are growing between the slabs.I need something to fill the gaps(about 1 inch across)but it needs to be something I can do one slab at a time.We have dogs and I can't protect the whole area from them while it sets.Inside the house I would use pollyfilla or something similar but have no idea what to use outside.Also it has to be low cost,can't afford to hire cement mixer.Any ideas?

cyclonebri1

A bucket, a hand full or 2 of cement, and a shovel of sand.

Mix together, and fill the gaps.

Unless you have something the size of cricket pitch, a bucket full should suffice.

PS, don't forget a bit of water;);)

m33r4

I have mixed my own cement with sand too in a bucket and applied it quite runny so it fills all the cracks. 2 years later it looks intact. I also have 2 dogs and they were not deprived for long as the cement sets quickly, especially in the weather we are having now.

Best wishes.

wallbash

and applied it quite runny so it fills all the cracks.

Which is the complete opposite of 'best' practice.

Mixture , firm enough to hold its shape But not to stain the hand , whilst grabbing a handful. A runny mixture is a weak and one which could so easily leave staining on the flags.

cyclonebri1

m33r4 wrote: »

I have mixed my own cement with sand too in a bucket and applied it quite runny so it fills all the cracks. 2 years later it looks intact. I also have 2 dogs and they were not deprived for long as the cement sets quickly, especially in the weather we are having now.

Best wishes.

And that I'm afraid is how to get cement stains all over the patio.

There is another method, never tried it but I do have the tool for the job. It's a pointing extruder gun, exactly like the thing you use for applying silicone, but on a bigger scale.

It's intended for speeding up the process of repointing brickwork, but I see no reason it can't be used on flags.;);)

bossymoo

I have heard you can brush the dry mix between the slabs into the gaps, and once you are sure its all brushed in well, water in with a fine rose attachment on your can.

Think I saw it on Ground Force!!!

My flags are mortared in but still get a few weeds / mossy bits and I brush over some salt now and again and they all crisp up and disappear. Don't want to do this near anything you want to grow, though!

wallbash

I have heard you can brush the dry mix between the slabs into the gaps, and once you are sure its all brushed in well, water in with a fine rose attachment on your can.

Do it correctly , then you can safely use a pressure washer.

Ground force had only 48 hours .......and some of its methods showed!!

cyclonebri1

wallbash wrote: »

Do it correctly , then you can safely use a pressure washer.

Ground force had only 48 hours .......and some of its methods showed!!

No, he is right, but is repeating what both you and me have been trying to get accross, maybe he's not read the whole thing.;);)

Yes you can use a sprinkler to set it off and yes, later, it will stand a pressure hose.

Alfrescodave

Don't mean to hijack the thread but I have a follow on question in that I had gaps between my patio slabs and repaired them with a 4:1 ratio of sand : cement. Some of the mortar is now crumbling ( 2 weeks later) and has little or no strength. Have to admit that the cement was alittle on the old side.

Any suggestions as to the cause of this or recommendations for a better mix

wallbash

that the cement was alittle on the old side.

Think you have answered your own question .
Personally , I go for the ready mix bag , the colour will be constant ,
You can mix a little at a time ....... just add a little amount of water , hold its shape but does not stain the hand. Push in with a small pointing trowel , use a 'chopping' motion , then a quick wipe to finish.

tim_n

I tend to use 1:3 mix of cement to sand. Probably the old cement as above.