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Exposed Aggregate or a Broom Finish?

The two finishes we are asked for most, compared on the things you notice after a year: bare feet, fallen leaves, glare off the surface and how obvious a stain is.

Updated September 2026 · Antioch Concrete

Both of these are ordinary concrete. Same slab, same base, same joints, same reasons to crack. The difference happens entirely in how the top is treated on the day, and because the pour is identical the choice really is about living with the result rather than about quality.

What each one is

A broom finish is exactly what it sounds like. Once the surface has been floated smooth, a broom is drawn across it to leave fine parallel ridges. It is the default residential finish, it is quick, and its texture is deliberate and directional.

Exposed aggregate takes the other route. Before the top layer of paste can harden it is washed off, or held back chemically and then removed, uncovering the stone that has been in there since the mixer. What you look at afterwards is the aggregate itself, standing very slightly proud.

Bare feet, which decides more of these than anything else

Walk on both and the difference is immediate. Broom is smooth with a fine tooth to it. Exposed aggregate is a field of small stones and it is firm underfoot, in a way that is pleasant on a pool surround and less so on the patio where people stand about in July with no shoes on.

Our honest observation from a lot of gardens: if the area is primarily for sitting, eating and children, most people prefer broom once they have stood on both. If it is a transition space, a surround or a path, the firmness never registers.

Leaves, grit and the maintenance nobody costs in

This is where the two genuinely diverge over years. A broomed surface has shallow aligned lines, so a brush or a hose clears it in one direction and it is done.

Exposed aggregate has a small hollow between every stone. Blossom in spring, leaves in autumn and windblown grit all year settle into those hollows and need working out rather than sweeping off. Under a tree, that is a real and repeating difference in effort.

The compensation is that exposed aggregate conceals dirt and staining far better. A busy surface hides a tyre mark, a dropped glass of wine or a patch of shade-damp in a way a broomed one does not.

Light, which surprises people

A broom finish is close to flat, so on a bright afternoon it reflects a lot of light back at the windows behind it. On a south-facing patio that can be genuinely uncomfortable, and it is the complaint we hear that nobody anticipated.

Exposed aggregate scatters light in every direction instead of bouncing it, so it reads softer from inside the house. If the surface sits directly outside a wall of glass, that is worth weighing before the finish is chosen.

Snow, which matters here and gets left out

Six months of the year one of these surfaces is easier to clear than the other, and it is not the one people expect from looking at them.

A broom finish takes a shovel cleanly. The ridges are shallow and aligned, so a blade runs across them and lifts what is on top. An exposed aggregate surface is a field of small raised stones, and a shovel catches on them rather than gliding, which makes clearing slower and noisier and is harder on the blade.

The counterweight is grip. Exposed aggregate holds a boot better when there is a thin film of ice or packed snow on it, so it is genuinely safer underfoot in the conditions where people fall. Which of those two matters more depends on whether the surface is one you have to clear every week or one you cross occasionally, and that is worth deciding deliberately rather than discovering in January.

The one specification that matters to both

Whichever surface you land on, the mix underneath it needs entrained air. The local specification runs three to six percent, and those bubbles are what give freezing water somewhere to go instead of pushing the surface apart.

This matters slightly more for exposed aggregate, because there is more surface area in contact with the weather and the paste holding each stone is doing visible work. A poorly aired exposed surface starts shedding stones, and a surface losing its stones cannot be repaired invisibly.

What each one asks of the crew

Relevant to you because it affects who should be doing the job. A broom finish is forgiving: the texture arrives at the end, over concrete that has been floated smooth, and a slightly uneven pass can be worked again.

Exposed aggregate is not forgiving at all. The surface paste has to be removed at the right moment, evenly, across the whole area, and that moment depends on the weather and on how the pour actually went. Too early and stones are dislodged and the surface is rough and loose. Too late and the paste has hardened and the stone will not expose without aggressive treatment that marks the finish.

There is no second attempt at either mistake. So on exposed aggregate it is fair to ask how often a crew does this particular finish, and to weigh that answer more heavily than you would on a broom job. It is also a reason the two finishes are not simply two prices on the same quote.

How we would choose

Sitting area, dining space, anywhere feet are bare: broom, and put the money saved into a larger area or a better base.

Pool surround, a path with a slope on it, a big expanse facing a lot of glass, or a garden with a lot of hard shade and damp: exposed aggregate, accepting that autumn will ask more of you.

And if the area is large enough to read as two spaces, use both. A border in one and a field in the other looks deliberate, breaks up an expanse that would otherwise be monotonous, and keeps the surface you actually stand on the one you wanted to stand on.

Which finish suits your garden is settled by standing in it, and that visit costs nothing and happens before we talk about money at all. The work itself is on concrete patio.