Breaking up bricks/slab with SDS drill, is that do-able??

[ken300]

Hi,

I've absolutely NO building experience at all so please, go gentle!

I moved into a terraced house a couple of years ago, the garden was (& mostly still is) a right mess. We've cleared about half of it with a view to building a patio & nice solid path. Hidden all over the garden were loads of bricks and chunks of concrete slabs which are now piled up, it would be nice (and cheap) to re-use these if possible as hardcore for the patio/path (although I don't think there'll be enough for both).

I've read elsewhere on the net that an 'SDS' type drill with roto-lock & a chisel bit is quite ok for breaking up bricks & concrete but would it be a reasonable method for breaking up the 150+ bricks & slab fragments I've got to make hardcore or is there a better/easier way?

Thanks for your guidance!

 

[r896neo]

A better way is to use a sledge hammer although it is only easier in some respects! certainly not physically but its quicker and cheaper if you ask me. you would be better off with a breaker rather than an sds drill as unless its a decent one it'll be too light duty. If your keen to use one you would want something between 5-10kg range for a job like that in my opinion. something like 7 or 8 would be ideal.

On a seperate but important note, hardcore like the kind you have is really only useful when you need to bring the level of an area up a bit because it is rubble of similar sizes and will not compact and under any path or patio you will still need to put a good layer of compactable MOT/ Blinding.

 

[Paul Barker]

Yes a lump hammer and bolster is more potent tthan a small 650 watt sds dril with roto stop.It is work which ever way you look at it.

Better using hand tools for that job which are cheap and no more effort that a pathetic little sds drill, whose purpose is to drill holes for rawl pluging screws and light chasing duties in plaster not brick.

Anything bigger or harder and you need a tool which is not worth your while buying so put some weight into the job by hand.

 

[ken300]

Thanks for both the quick replies!

r896neo, am I right in thinking that you're saying that because all the chunks of brick will be around about the same sort of size that they won't 'interlock' & bind together well so they won't form a solid stable foundation for the top surface & it'll become uneven over time (I don't want to mess things up by trying to do it on the cheap!)?

If so is the same also true of any hardcore that's made up of evenly sized lumps? I think a bit more reading is required!!

What you've both said was what I half suspected, it sounds like if I try and buy an SDS drill that'll both chisel up bricks in the garden and be light enough to use to put up shelves & stuff round the house it'll just be a big compromise, with it being no good for either, oh well

I imagine I'll find a use for the bricks I've got if I'm not going to use them as hardcore (maybe edging the path??) but I can't think of anything useful I can do with the ugly old concrete slabs & bits of slabs that I've got, have you got any suggestions for anything that I can do with them (other than just bunging them in a skip!)?

Thanks again for the replies, much appreciated!

 

[ken300]

Just a thought r896neo (I've got to be quick, I'm in the middle of cooking tea), the path I'd like would be topped with self-binding gravel (the same thickness as the hardcore underneath). In theory if the path becomes uneven you should be able to quite easily scrape up the top layer of compressed gravel so that it becomes loose gravel again, level it off & then re-compress it flat again.

Does that have any bearing on your thoughts about weather broken bricks would be ok as hardcore??

Thanks!

 

[r896neo]

Basically self binding gravel is a more attractive slightly finer version of MOT which consist of all sizes of particles from 20mm down to dust. Because of this the dust and smaller bits compact together and bind a little giving a nice solid sub-base.

In contrast hardcore in the form of rubble and including clean washed stone of all similar sizes is uncompressible. Hence why you use it around drainage pipes etc. Brick rubble as hardcore is fine and will not compress but in theory can move laterally and or not sit flat and leave voids between itself which is where when pressure is put on it the voids may collapse and cause settling/ sinking.

If you want to use some of your bust up concrete lay it only in a single layer and then rake compressible MOT over it to fill in all the voids. Compact it with a plate to shake it in well rake another inch over the top and repeat if necessary. If you do it this way then it is at less risk of settling.

On the whole though your thoughts about re-compacting at a later date are completely correct!

 

[ken300]

r896neo,

I get what you're saying about hardcore with lumps of the same size leaving voids/pressure points etc & everything settling over time, that makes perfect sense!

It sounds like breaking up the slabs etc might be more work than its worth, we'll undoubtedly need another skip at some point maybe they're best just being thrown in there (besides MOT isn't that expensive)!

Another thought, would MOT give a good enough surface for a rough & ready path when used on it's own whilst we finish work in the rest of the garden (like demolishing a brick built shed) here's my idea:
Prepare the path in its final location (dig out a channel say 100mm depth), fill half its depth with just MOT & compress it, leave it in that state for a while, walking on it to do the donkey work in the rest of the garden then once we're finished put the finishing layer of self-binding gravel over the top to stop the expensive (compared to MOT) self-binding gravel becoming all chewed up unnecessarily??

Thanks again, your advice is just what I need!!!

 

[r896neo]

If your going to be getting a skip anyway then i agree completely with all you have said! Your plan is perfect. MOT even just walked on a bit will give a very good usuable path. once it gets a little damp from rain it forms a bit of a crust anyway which keeps the dust down too.

 

[ken300]

r896neo,

It sounds like I've got a plan then!

Thanks for all your help, I'd be lost without it!

 

[jctilingservices]

break them up with a sledge hammer, use as hardcore, hire a wacker ( about £20 per day) whack your hardcore then cover with sharp sand and whack that, theres your hard standing, get it screeded and lay your path.
Size of the pieces has absolutely NOTHING to do with air pockets etc as they will be filled with your sharp sand then compressed.HEY PRESTO

 

[Thermo]

and how do you get the sharp sand in the voids below the hardcore? give it a few good downpours and the rain will pour the sand down and lead to sunken or hollow areas in the path or patio.

 

[r896neo]

''and how do you get the sharp sand in the voids below the hardcore? give it a few good downpours and the rain will pour the sand down and lead to sunken or hollow areas in the path or patio.''

couldn't have put it better myself.

 

[paulandfrodo]

spend as long as possible thinking of someone you hate and hit it with sledge hammer.

When you do get round to binding with sand, use a hose pipe and whacker...

Oh, and when you think your done breaking it up - do it a little more.

 

[jctilingservices]

''and how do you get the sharp sand in the voids below the hardcore? give it a few good downpours and the rain will pour the sand down and lead to sunken or hollow areas in the path or patio.''

couldn't have put it better myself.

read my post correctly, i said lay the hardcore and whack it, THEN lay sharp sand and whack that. There will be no voids at all if it is whacked correctly

 

[r896neo]

It's hardcore its not compactable! it just sits there no matter how much you whack it. Hence why compactable MOT is used as a sub-base.

What thermo said is exactly what happens if you lay hardcore and then put sand over it. The best way you can do it is as i suggested by putting the pieces in one single layer slightly spaced out and fill in between them with mot and compact that.

I have had jobs to lift and relay paving because the jobs done using your method where the sand had washed down into it and the paving sank.