book collections email follower instructable user

Making an Exposed Aggregate Concrete Path

Featured
Picture of Making an Exposed Aggregate Concrete Path

I love working with concrete because it's tough and versatile and relatively cost effective.

In this instructable I'll be jazzing up a new footpath by exposing the aggregate.

There are a few ways to do this, and many commercial operators use a high pressure spray to blast off the top surface of cement.

The method I will show you doesn't require any special tools other than what you would use when mixing and laying concrete...it doesn't use any surface disruptors or acid, nor does it use a water blaster.

So if you can lay concrete, you can do this.

If you're concerned about committing to a large project, you may want to do a test run of the method by making some pavers or tiles on a small scale. Then when you're comfortable with the process you can create your large project.

Step 1: Box; Mix; Pour; Lay; Screed; Trowel

Picture of Box; Mix; Pour; Lay; Screed; Trowel
IMG_5868.JPG
IMG_5866.JPG
IMG_5903.JPG
IMG_5888.JPG
IMG_5869.JPG

We mixed our own concrete onsite but this method will work with premix concrete that has a normal cure time. A rapid set concrete should not be used.

I won't go through the specifics of the above steps, but so you know...

- box the area

- mix the concrete

- pour the concrete

- lay and screed the concrete

- trowel the concrete smooth

Pro tip

Curve your path...it's much nicer to the eye and can be easier to create than a straight edge.

panzer1yesterday
good job !
gcai_fwb2 days ago
Nice job! and it looks great - just the idea I need for finishing a planned 'stepping' stone walkway using one of these https://www.quikrete.com/athome/walkmaker.asp - I'm going to use the "country stone" pattern.
ps. nice touch with the Kiwi slang - I'll have to dig out and reread my old Footrot Flats graphic 'novels' again
That looks great! Does the finish coat make it slippery when it's wet?
I've been wanting for years to make some hypertufa planters; I wonder if I could use this technique on them...
Minnear Knives (author)  dragon flyer4 days ago
It's not slippery due to the texture of the pebbles coming through. If it was smooth concrete, yes it would be slippery when wet.
Rordes4 days ago
Please people do not do exposed this way. This is the equivalent to driving a steam powerd car to a supercar. This person would niy have the slighest clue on how to concrete. Oh I've been concreteing for more than 20 years.
20190701_123845.jpg
Fantastically beautiful walk. Very appealing. Very artsy. Great job.
one tip from one who has don it many times before, mix a pound of sugar with a bucket of lukewarm water put it in a garden weed sprayer and gently wet the surface just before it goes off then let it set. Ones set you can gently rinse of the concrete as the sugar has killed the surface layer of cement
Which stage of the process do you mean by 'going off ' ? Do you mean right after having pushed and trowelled in the pebbles? Or when it's firming up? or just before rinsing the concrete? Please Clarify, thank you.
"Going off " is just a term we use it means just before the cement goes
to sets, the sugar stops the chemical reaction and stops the cement
from sticking to the stones, you could do the same with a hydrocloric
acid / water solution, but that could be a lot riskier because the acid
is much more aggressive and could loosen the stones. the same thing can
happen when you don't use the sugar solution as you may have to rub to
hard to get the stones clean
Minnear Knives (author)  Feelunike7 days ago
'Going off' aka the concreting beginning to set and/or firm up. This is after the stones have been pushed into the concrete and trowelled over. My concrete was ready to water and brush off after this, about 8 hours later. So yes, just before rinsing the concrete. Thanks for your question.
Geographical query, I think; what does 'going off' mean?
"Going off " is just a term we use it means just before the cement goes to sets, the sugar stops the chemical reaction and stops the cement from sticking to the stones, you could do the same with a hydrocloric acid / water solution, but that could be a lot riskier because the acid is much more aggressive and could loosen the stones. the same thing can happen when you don't use the sugar solution as you may have to rub to hard to get the stones clean
Minnear Knives (author)  dragon flyer7 days ago
Yes geographical (New Zealand) slang for setting or firming up.
Minnear Knives (author)  gerryveldkamp7 days ago
That's a great tip, thanks for sharing.
Minnear Knives (author)  gerryveldkamp7 days ago
Great tip!
Alex in NZ9 days ago
This looks beautiful. Well done and thank you for all the little tips :-)
Minnear Knives (author)  Alex in NZ7 days ago
Thanks for your comment. I'm in Geraldine South Canterbury, where in NZ are you?
I'm up in Welly. I would say that it's cold today, but compared to Geraldine... :-)
sharpstick7 days ago
I think a section of concrete that long should have expansion joints.
What about rebar? Every large chunk of concrete I've seen done has rebar in it.
Minnear Knives (author)  cfuse7 days ago
The concrete is quite thick and it's handling only foot traffic.
FlorinJ cfuse7 days ago
It lays flat on the ground and doesn't have anything on top that should make it act like a 3D structure. It will behave like a foil - very tough foil, but still a foil, that will be eventually torn apart by the ground moving underneath with seasonal temperature changes.
Minnear Knives (author)  FlorinJ7 days ago
There are many concrete paths around here that are coping well in this climate. Thanks for your thoughts.
Pros who did my concrete front driveway and walk (area subject to winter freezing) used wire mesh, not rebar which would be overkill. They placed expansion joints in driveway every 10’.... which was expected. But to avoid expansion joints that would ruin the look of the walkway, I slow cured it... kept lightly watered for first month, and now in process of burying gravel with weedblock fabric along perimeter of walkway for water management / freeze control... to avoid stress from irregular lifting in a hard freeze.

Anyway, great-looking aggregate walkway... so much nicer than standard concrete!
Minnear Knives (author)  sharpstick7 days ago
It's about 8 m long and could have expansion joints cut in. Thanks for your comment.
SusanP1707 days ago
It looks great! ..... A lot of helpful hints along the way were really appreciated.... I will definitely be trying this once I research what a Canadian winter might do to it, or what additional steps may be required.... Thank you!
Minnear Knives (author)  SusanP1707 days ago
Looking forward to a progress report. All the best in Canada from New Zealand.
AnandM5410 days ago
Looks brilliant idea !!
Minnear Knives (author)  AnandM547 days ago
Thanks.
dlarson39 days ago
This piece I did 5 yrs ago. It has held up pretty well. The aggregate is starting release as the concrete erodes. Pro tip:
Dont blast it with a pressure washer to remove mold or dirt. Bleach, water and broom!.
15625233029851998055960779968366.jpg
Minnear Knives (author)  dlarson37 days ago
Looking good, thanks for sharing. Good tip.
DDW_OR7 days ago
NOTE - add the water for 2 bags, then add one bag at a time, mixing each bag