Most delivery day problems have nothing to do with the concrete. They happen because the lorry cannot get close enough, or cannot stand safely once it arrives. Sloping and awkward ground is the number one cause.
This guide is for the person planning the access, not the person finishing the slab. If you want help with the pour itself, read our companion guide on how to pour concrete on slopes and uneven ground. This page is about a different problem: getting the lorry in and the concrete out.
Sort this out before you book, and delivery day becomes boring. Boring is exactly what you want.
Why slopes cause so much trouble
A fully loaded concrete lorry can weigh more than 32 tonnes. That is a huge amount of weight sitting on a small patch of ground.
On flat, firm ground, that weight spreads out, and everything is fine. On a slope, three things change at once:
- The weight shifts towards the downhill wheels, so the ground on that side takes more load.
- Soft ground gives way more easily, and a sinking wheel makes the lean worse.
- Concrete flows downhill on its own, which is helpful in one direction and useless in every other.
A driver who arrives, looks at your ground and decides it is not safe is not being difficult. They are following the rules they work to. It is far better to hear that on the phone a week early than on the day with a full load already mixed.
Where a mixer can safely stand
The lorry needs somewhere to park that is firm, reasonably level and well drained. The Health and Safety Executive is clear that vehicle parking areas should be firm, level and not slippery, and that any vehicle on a slope must face up or down the hill rather than sit sideways across it.
That last point catches people out. A driveway that falls steeply from side to side is often a bigger problem than one that runs steeply up or down.
Here is what to check before you book:
Access route. You need roughly 3.5 metres of width and about 4.5 metres of overhead clearance. Low branches, phone lines, carport roofs and narrow gateposts all count.
Ground surface. Tarmac, concrete and compacted hardcore are all good. Soft lawn, fresh topsoil, muddy tracks and newly backfilled trenches are not. If the ground is soft, temporary road matting or a load of compacted aggregate will usually solve it.
Hidden weak spots. Drain covers, inspection chambers, septic tanks, soakaways and recently dug service trenches will not take 32 tonnes. Mark them and keep the lorry away.
Standing position. Pick a spot where the lorry can stop, unload and then drive out or reverse out safely. A vehicle that has to turn on soft, sloping ground is asking for trouble.
If you cannot create a safe standing spot near the pour, that is not the end of the plan. It just means the concrete has to travel further than the chute can carry it, and there are good ways to do that. Our guide on why concrete pumping is ideal for tight access sites covers the awkward layouts we see most often.
How far will the chute actually reach?
This is where expectations and reality drift apart.
A standard mixer chute gives you roughly 2 to 3 metres from the back of the lorry. Add extra chute sections, and you might stretch that to 4 or 5 metres. That is it. The chute is a short slide, not a delivery pipe.
Gravity matters too, and it does not always help you.
Pouring downhill from the lorry works well. The concrete has somewhere to go, and the chute angle does the work.
Pouring uphill from the lorry does not work at all. The chute has to run downwards. If your pour is above the level of the lorry’s discharge point, gravity is working against you and the chute is useless no matter how many sections you add.
So on a sloping site, where the lorry stands relative to the pour matters more than the distance in metres. Ten metres downhill can be easy. Three metres uphill can be impossible.
There is one more catch with a steep chute run. Concrete that drops too fast can separate, with the stones running ahead of the paste. That gives you a patchy, weak result. A controlled flow beats a fast one every time.
When barrow runs make sense, and when they waste your load
Barrowing is the traditional answer, and for small jobs it is still the right one.
A builder’s barrow holds roughly 0.05 to 0.08 cubic metres. So one cubic metre of concrete is about 15 to 20 barrow loads. A full 6 cubic metre load is somewhere near 100 barrow runs.
Now add a slope. Pushing a loaded barrow uphill, over a plank, on a wet day, is slow and tiring work. The pace drops sharply after the first twenty runs.
The problem is that your concrete is on a clock. Ready-mixed concrete stays workable for roughly 60 to 90 minutes after batching, and hot weather shortens that. If your barrow team cannot move the whole load inside that window, the last of it goes off before it is placed. You have then paid for concrete you cannot use, and you have a cold joint in the middle of your slab.
As a rough rule of thumb:
- Up to about 1 cubic metre, on a short and gentle run: barrowing is fine with two or three people.
- 1 to 2 cubic metres, or any uphill run: barrowing is possible, but you need a proper team and a planked route.
- Above 2 cubic metres, or a long, steep or muddy run: think seriously about a pump.
When a pump becomes the cheaper option
People often see a pump as an extra cost. On a sloping site it is frequently the cheaper choice once you count everything.
Compare the real cost of moving the mix by hand. That is several people for half a day, planks and barrows, the risk of concrete going off before it is placed, and the chance of a churned-up garden that needs putting right afterwards. Set that against a pump that puts the concrete exactly where you want it in well under an hour.
| Option | Realistic reach | Best suited to | Watch out for |
|---|---|---|---|
| Mixer chute | 2 to 5 metres, downhill only | Drives, garage bases and footings the lorry can reach | Useless if the pour sits above the lorry |
| Barrow runs | Any distance, but slow | Small pours up to roughly 1 to 2 cubic metres | Uphill runs, the 60 to 90 minute clock, tired crews |
| Line pump | Up to 150 metres of pipe | Back gardens, tight gateways, long or uphill runs | Bends cost you reach, and the mix must suit pumping |
| Boom pump | Around 24 to 42 metres of boom | Large volumes, upper floors, pouring over obstacles | Needs firm, level ground for the outriggers |
A line pump is the usual answer for domestic sloping sites. The pump sits on the road or drive, the lorry discharges into it, and a flexible hose runs through the side gate and up the garden to the pour. Nothing crosses your lawn except a hose. You can see the full range of options on our concrete pumping Cambridgeshire page.
One important point on boom pumps. The boom itself solves the reach problem, but the pump still needs somewhere firm and level to set up its outriggers. On a steeply sloping site a line pump is often the more practical choice, even though its reach is measured in pipe rather than boom.
Working out the reach you need
Do not measure in a straight line across the map. Measure the route the hose will actually take.
Walk it. Out of the gate, along the path, round the corner of the house, up the garden. That is your real distance, and it is usually longer than people expect.
Bends cost you reach as well. Every 90-degree bend behaves roughly like an extra 3 to 5 metres of straight pipe, because the concrete has to be pushed round it. Height costs you reach too, since pumping uphill is harder work than pumping along the flat.
For the full picture on what different pumps can manage and what eats into their range, read how far can a concrete pump reach?
The simplest thing you can do is describe your site to us when you ring. Where the lorry can stand, where the pour is, how far apart they are, and whether the ground rises or falls between them. We will tell you what will work.
Your pre-delivery access checklist
Run through this a few days before delivery, not on the morning.
- Confirm the lorry’s standing spot. Firm, drained, and either flat or facing up or down the slope rather than across it.
- Measure the access route. About 3.5 metres wide and 4.5 metres of headroom, all the way in.
- Check for weak ground. Mark drains, chambers, tanks and any recently dug trenches. Keep the lorry off them.
- Decide how the concrete travels. Chute, barrows or pump. Be honest about the slope and the volume.
- Clear the discharge area. Move tools, materials, cars, bins and anything else in the way.
- Plan the hose route if you are pumping. Unlock gates, remove obstacles and count the bends.
- Line up enough people. Placing and finishing is time-sensitive work, and a slope makes it harder.
- Have a wash-out point ready. A lined pit or a designated area, agreed in advance.
- Check the weather. Heat speeds up setting, rain makes slopes slippery and unsafe.
- Tell us about anything unusual. A tight bend, a soft verge, a steep drive, overhead cables. Surprises cost time.
For a fuller walk-through of what happens on the day, see ready-made concrete delivery: what to expect and how to prepare.
Talk to us before you book
Sloping sites are normal for us. We mix on site using volumetric mixers, so you get exactly what you order with no waste, and we can adjust as the pour goes on.
The most useful five minutes you can spend is a phone call describing your access. Tell us where the lorry can stand, where the concrete needs to go, and what sits between the two. We will tell you honestly whether a chute will do it, whether barrows are realistic, or whether a pump will save you money and a very long afternoon.
Call Cardinalis Concrete on 01954 288027 or email enquiries@cardinalis.co.uk. We deliver across Cambridgeshire, Suffolk, Hertfordshire, Essex and Norfolk.
