How much materials for footpath please?

Hermy

Hi, I want to put down a concrete footpath in my back garden. I'll be doing the mixing myself and I'd be grateful if someone could give me an idea of how much gravel and cement I'll need to buy.
The area to be covered is 36 foot by 3 foot and about 4 inches deep.

Thanks in advance.

EDIT: Also, what's best to stop concrete from dusting?

harry21

Assuming the following.

12m by 1m by .1m footpath = 1.2 cubic meters

I would be ordering 2 tonnes of aggregate and 10 25kg bags of cement.

Hermy

Thanks a lot Harry.:)

Rhys Essien

Would it be easier to contact your local concrete company.You could probably get the concrete (25N10) for less than €200 delivered.Save a lot of hard work.

Dupont

harry21 wrote: »

Assuming the following.

12m by 1m by .1m footpath = 1.2 cubic meters

I would be ordering 2 tonnes of aggregate and 10 25kg bags of cement.

you want 20 bags of cement 10 per tonne bag.mixed 2 tonne bags last weekend and used all but a barrowfull and 19 bags.mixed at 4-1

harry21

Dupont wrote: »

you want 20 bags of cement 10 per tonne bag.mixed 2 tonne bags last weekend and used all but a barrowfull and 19 bags.mixed at 4-1

Actually, that right. I was going on 20% cement in a tonne and forgot it was 2 tonnes you needed.

Whoops! - Lucky there is more than one of us here!!

Hermy

:eek::eek:
I've just come back to thank harry for his advice.
I was left with a couple of barrows of gravel over which was perfect as it will come in handy somewhere else.
But now it seems like I might not have used enough cement.:o
What's the worst that can happen?
Will the whole thing crack up or will it just dust a bit?

harry21

How many bags of cement did you use?

jimbomalley

Hermy wrote: »

:eek::eek:
I've just come back to thank harry for his advice.
I was left with a couple of barrows of gravel over which was perfect as it will come in handy somewhere else.
But now it seems like I might not have used enough cement.:o
What's the worst that can happen?
Will the whole thing crack up or will it just dust a bit?

dont worry about your path...it will be fine but make sure you cut expansion joints every 5m max along the length else it will crack in random places. cut the joint about 25mm deep with a consaw/angle grinder to encourage the path to expand and crack at the joint

dnme

harry21 wrote: »

Assuming the following.

12m by 1m by .1m footpath = 1.2 cubic meters

I would be ordering 2 tonnes of aggregate and 10 25kg bags of cement.

Harry
How do you work this out (just out of interest)? I am picturing a box 1.2m wide, deep and high. It's not that big. Surely you'd never get 2tonnes of stuff and 10 bags of cement into that space?

audi a4 2008

jimbomalley wrote: »

dont worry about your path...it will be fine but make sure you cut expansion joints every 5m max along the length else it will crack in random places. cut the joint about 25mm deep with a consaw/angle grinder to encourage the path to expand and crack at the joint

this can work but i find it better to do the joints with a edgeing trowel as it puts in a better finish and also makes the path nicer looking

harry21

dnme wrote: »

Harry
How do you work this out (just out of interest)? I am picturing a box 1.2m wide, deep and high. It's not that big. Surely you'd never get 2tonnes of stuff and 10 bags of cement into that space?

The specific gravity of the sand/aggrgate is about 2.4 or thereabouts when wet, meaning a cubic meter is about 2.5 tonnes!

At Hermy, your mix will work out at about 8/9 : 1 to one which should be fine for foot traffic. As mentioned you could cut it with a grinder. This just forces the contrete to crack where you want it to and will allow for expansion and contraction.

Hermy

harry21 wrote: »

How many bags of cement did you use?

I used all ten bags and it looks fine so far.:)

harry21

Hermy wrote: »

I used all ten bags and it looks fine so far.:)

Great to hear... Givent that you used all the cement and I'm guessing 1800 kg of aggregate, I'd estimate (dependedin on how wet you made the cement) that your mix would easliy be a 15N/mm2 mix.

That means it can withstand approx. 15kg per square mm. The average person, say 80kg standing on the footpath (42500mm2 of surface contact) will apply 8,000 times less pressure that this.

All in, your good for footfall.

Hermy

harry21 wrote: »

All in, your good for footfall.

Sounds good - thanks again Harry.

jimbomalley

audi a4 2008 wrote: »

this can work but i find it better to do the joints with a edgeing trowel as it puts in a better finish and also makes the path nicer looking

not denying this but if the path is already poured....

audi a4 2008

jimbomalley wrote: »

not denying this but if the path is already poured....

yes jimbomalley youre right if the path is poured and u do it the next day yes its fine.
my point was on the day of pour its easyier to do it all in one day and puts a nicer finish.thats all