Garage Entrance Concrete Repair (RK?)

[Cunning Plan]

Looking for advice, I haven't got a picture but need to repair a ramp that goes into the garage. It is potholed / worn in places where it should be flat.

I mixed up some cement and concrete thinking I could get that smooth enough to apply over the top but because of the consistency, it was hard to get flat without churning it all back up again.

I did some research on the net and saw people using 'lycra / silicone' concrete where you have to mix two chemicals A and B into a mix. It looks a lot easier to apply and is design to repair exactly what I am trying to do.

Question is, should I bother going to look for this stuff or am I doing this completely the wrong way? Has anyone got any experience with the 'plastic' concrete stuff?

[Roadkill]

If it's only minor holes I would forget a concrete-based mixed and just use a "heavy" cement mix (1 part cement / 4or5 parts sand).

Concrete has stones in to create a structure . . . if you're merely filling holes cement will be fine and as it's a finer mix you'll be able to apply it without it dragging out . . . .

For best finish apply with a trough and then lightly brush-over with a wetted (but not soaking) hand brush . . . . this will act to feather the edges a bit.

I'd also recommend you add plastiser (sold at wickes in 5L containers but I may have a small amount if you need it) - it makes the mix more "sticky" so will help it hold in place - especially in vertical repairs.

Whenever you fill a hole in an existing structure (your ramp) always brush/hoover the dust out then damp the area down to improve adhesion.

[Cunning Plan]

Quoting: Roadkill

Concrete has stones in to create a structure . . . if you're merely filling holes cement will be fine and as it's a finer mix you'll be able to apply it without it dragging out . . . .

Ar, see I think most of building is just knowing what is used for what - I wasn't sure but as the original structure was concrete I guessed to fill it again with concrete.

Cool! So just mix cement with 'plastiser' - which isn't plaster? - just making sure..

I might give it a go with no concrete first - just cement as it was already too 'sticky' as it was which meant when I went over it with trowel / wood to try and flatten it, it would all get pulled up like a peanut-butter type of consistency if you see what I mean

Then brush over with a damp hand-brush

Quoting: Roadkill

Whenever you fill a hole in an existing structure (your ramp) always brush/hoover the dust out then damp the area down to improve adhesion.

I remembered to brush but not damp.

[Roadkill]

Quoting: Cunning Plan

it was already too 'sticky'

No, that sound's like it was too rough.

This is the stuff (don't use as much water with this stuff) :

http://www.wickes.co.uk/Mortar-Plasticiser/invt/240669\" target=\"_blank\" rel=\"nofollow\">http://www.wickes.co.uk/Mortar-Plasticiser/invt/240669

(Spelt it wrong before - my bad )

It's cheaper than it used to be - that's for sure.

[Cunning Plan]

Cheers RK, I'll give it a go when I can get to bandq/Wickes

[Roadkill]

Quoting: Cunning Plan

bandq/Wickes

[Cunning Plan]

Quoting: Roadkill

/Wickes

[nick69]

cement MIGHT be strong enough to last and dont buy plast'er, use washing up liquid . A quick squirt. I wouldnt use a 4/1 mix though 3/1 would be better.

But concrete is the correct stuff to use, you're dragging it out because you are working it too much, best to let it go off for an hour then use a wet brush. Mix it with  small agg' or even pea shingle instead of 25mm stones (standard). after leaving for an hour, wet the trowel not the mix.

[Andy]

When I put a ramp in a barn, I dropped some lengths of steel in it, just to reinforce it a bit. Has a tractor going up and down and has no worries yet

[Cunning Plan]

I hear RK... I hear Nick69... I hear Andy...

But which one is best??

[Andy]

I'm not disagreeing with the above

Just saying, reinforcing a ramp or point where there is heavy use is a good idea. Will make it really solid, are you putting any foundations down?

[Roadkill]

Just how big are the holes in the ramp you've got ?

If they're bigger than fist-sized you'll need a pea-shingle mix as Nick said . . . I'd imagined them to be not that big, though.

Washing up liquid does work, too - although for the price I normally just use the plasticiser . . .

[Cunning Plan]

Quoting: Roadkill

If they're bigger than fist-sized you'll need a pea-shingle mix as Nick said . . . I'd imagined them to be not that big, though.

They aren't deeper than fist-sized- they are about 300mm round and 10mm deep or so.

How do you do a pea shingle mix? The concrete I have is already mixed with small stones - can you buy concrete on its own to then add sand or stones to it then?

Quoting: Roadkill

Washing up liquid does work, too - although for the price I normally just use the plasticiser . . .

Roger.

[Roadkill]

Quoting: Cunning Plan

They aren't deeper than fist-sized- they are about 300mm round and 10mm deep or so.

As I first thought.

In that case using pea-shingle won't help . . . you want cement to effectively act as a screed.

Quoting: Cunning Plan

How do you do a pea shingle mix? The concrete I have is already mixed with small stones - can you buy concrete on its own to then add sand or stones to it then?

Concrete is basically cement with stones added so using pea shingle would be like mixing up cement and adding pea-shingle.

Ready mixed balast is probably what you've got - it's got 20mm stones and sand in it - you then add the cement and water.

Have a read of this :

http://www.wickes.co.uk/Good-Idea-Leaflets/Good-Idea-Leaflets/pcat/13builmaterials\" target=\"_blank\" rel=\"nofollow\">http://www.wickes.co.uk/Good-Idea-Leaflets/Good-Idea-Leaflets/pcat/13builmaterials

[Andy]

Yeah, as RK says probably best just buying a bag of cement and sand and screeding the top. The only thing with that is if it's taking cars or heavy equipment it's liable to breaking up and falling apart.

Got any pics?

[Cunning Plan]

Quoting: Roadkill

oncrete is basically cement with stones added so using pea shingle would be like mixing up cement and adding pea-shingle.

Ready mixed balast is probably what you've got - it's got 20mm stones and sand in it - you then add the cement and water.

Have a read of this :

http://www.wickes.co.uk/Good-Idea-Leaflets/Good-Idea-Leaflets/pcat/13builmaterials\" target=\"_blank\" rel=\"nofollow\">http://www.wickes.co.uk/Good-Idea-Leaflets/Good-Idea-Leaflets/pcat/13builmaterials

Well explained sir. if there was a 'thanks' system on this forum, I'd be sure to 'give you one'.

Quoting: Andy

Yeah, as RK says probably best just buying a bag of cement and sand and screeding the top. The only thing with that is if it's taking cars or heavy equipment it's liable to breaking up and falling apart.

It is taking cars and equipment

So how can I stop it breaking apart if I can't use concrete as the pebbles in it are too big and cause it to break-up / tare-away?

I was just going to try cement, sand and that plasticiciciciicicier stuff to see if it helps application..

Quoting: Andy

Got any pics?

Naw sorry dude, it's all covered in my first attempt anyway - so a right mess.. I need to repair before I get chucked out

[Roadkill]

Quoting: Cunning Plan

It is taking cars and equipment  

Providing you prepare it sufficiently (sweep / hoover), skim it well (good finish), force out the air and use a firm mix that'll be absolutely fine.

You can by a ready-mix patch repair concrete mix, too, but I think you'll do fine with a mix it yourself.

[Cunning Plan]

Okay, pictures to follow.

Sand, cement, plasticiiciciciciser and a wet brush.

[Cunning Plan]

Couple of things didn't quite work how they should have. First attempt I used 'sharp sand' which meant it was hard to get flat - I didn't think it would be that 'rough'. Then I ran out of normal sand so ended up using a strong mix of concrete to soft-sand..

The original concrete was a nice sandy colour, the repair is a grey - typically concrete colour.

How do you change the colour of concrete without diluting it too much with sand which would then become more of a motor mix? (I don't mean NOW, I just would like to know for future reference..)

[Roadkill]

If the concrete is a sandy colour then there's too much sand in it.

Concrete should dry a light / medium grey.

Soft sand isn't the correct sand to use - this is for use under paving, for example, for levelling . . . . . it's used in bricklaying, too, but not in concrete.

[Roadkill]

Quoting: Cunning Plan

How do you change the colour of concrete

You can get cement dyes . . . . typically used for dying cement for ornamental uses . . . but I suppose it'd work in concrete too.

[Roadkill]

This is a useful link (bit late now) I used for when I did the garage floor . . .

http://www.diydoctor.org.uk/projects/mixing_concrete.htm\" target=\"_blank\" rel=\"nofollow\">http://www.diydoctor.org.uk/projects/mixing_concrete.htm

[Cunning Plan]

Quoting: Roadkill

Soft sand isn't the correct sand to use

Problem is though bud, when I used the sharp sand and tried to flat over it, you ended up with the small stones poping up..  Don't forget the repair was only about 4/5mm deep!

Do you think I should have just used pure concrete as this would have been almost like a putty to put on top.

Quoting: Roadkill

You can get cement dyes . . . . typically used for dying cement for ornamental uses . . . but I suppose it'd work in concrete too.

Interesting, I'll have to grab some pictures so you can help me work out how they managed to get the sand coloured garage floor

Thanks for all you help so far dude - and answering my n00b questions

[Roadkill]

Quoting: Cunning Plan

Don't forget the repair was only about 4/5mm deep!

If it was only that deep you should've used cement as a "screed" - ie. the same concrete mix without any stones . . . Stones are used to give it body (like turning Iron into Steel) . . . . If the stones are 10-20mm there's no way you're going to fix a hole 5mm deep.
A hole that small is awkward so requires good prep to maximise adhesion.

Adding too much sand WILL make the mixture brittle on drying . . . . There has been cases of entire houses being demolished because of high sand content (sand is alot cheaper than cement so builders will tend always use more sand then they should) !!

As an example run your fingers along a cement line on your house - I'll guarantee you'll get powdery sand drop out . . . . You should not get that with concrete - especially if it's been properly smoothed.

[Cunning Plan]

Quoting: Roadkill

If it was only that deep you should've used cement as a "screed" - ie. the same concrete mix without any stones .

See that's where I'm struggling - I looked at all the different types of sand and I found:

Kiln-Dryed Sand - I'm guessing no good.
Soft Sand - OK?
Sharp Sand - Good for creating a structure - right? But stones are too big
Shingle - No good

So out of all of that I got the soft sand, but you say

Quoting: Roadkill

Soft sand isn't the correct sand to use

But I couldn't find any other type of sand