Compactors: Plate vs Roller vs Rammer
For open areas with granular soils, gravel or asphalt, a plate compactor is the standard choice.
For narrow trenches, cable channels or confined spaces, a rammer (sold by Riequip as a "trench compactor") gets into tight spots a plate can't.
For large open areas like road base or bigger civil projects, a roller covers more ground per pass.
A note on naming: Riequip's site lists this category as "Trench Compactor" rather than "Rammer". It's the same product, confirmed as a genuine percussive/reciprocating design, just marketed under a different name. This guide uses "Rammer" as the heading since that's the common trade term buyers search for, and explains the naming below.
Who this guide is for
Builders and landscapers
Compacting paths, patios and footings.
Utility and drainage contractors
Working in narrow trenches and cable channels.
Civil and earthworks crews
Compacting larger open areas efficiently.
Compactor types compared
| Factor | Plate compactor | Rammer (trench compactor) | Roller |
|---|---|---|---|
| Compaction method | Vibrating plate | Percussive reciprocating shoe ("jumping" action) | Vibrating drum(s) |
| Best suited to | Granular soils, gravel, asphalt | Cohesive/mixed soils in narrow or confined spaces | Larger open areas, road base |
| Typical width | 300-600mm plate | 280-330mm shoe | Drum width varies by model |
| Best suited to | Open, accessible areas | Trenches, cable channels, tight corners | Large open areas, roads, car parks |
Riequip's current range by category
Alto and Altrad Belle forward range
Alto CMF60 (60kg, Honda GX160, $1,790 + GST) up to Altrad Belle PCX500 (96kg, petrol, $2,890 + GST), for general open-area compaction.
Alto and Altrad Belle reversible range
Alto CMR80 (80kg, $3,180 + GST) up to Altrad Belle RPX59/65D (440kg, diesel, $18,990 + GST), for larger jobs needing back-and-forth travel without turning the machine.
Alto and Altrad Belle rammer range
Alto CNR70 (70kg, Honda GXR120, percussive/reciprocating shoe, 14kN impact force, $3,690 + GST) up to the Yanmar diesel-powered Altrad Belle RTX80D (80kg, $6,790 + GST), for trenches, cable channels and confined spaces.
Altrad Belle twin-drum roller
Altrad Belle TDX650A twin-drum roller (675kg, Yanmar diesel, $21,900 + GST), for larger open areas and road base work.
As one example, the Alto CNR70 rammer is a genuine percussive design (not a vibrating plate), delivering 14kN of impact force at 640-680 impacts per minute, purpose-built for the narrow trenches and confined spaces a plate compactor's wider footprint can't reach. Riequip's full compaction range is browsable at riequip.co.nz/collections/plate-compactors.
Why this recommendation fits
The three compactor types use genuinely different mechanisms suited to different soil and space conditions, not just different sizes of the same tool. A vibrating plate works well on granular soils by shaking particles into place, but struggles in narrow trenches where there's no room to manoeuvre a wide plate. A rammer's percussive action delivers a concentrated, high-impact force through a narrower shoe, which suits confined spaces and cohesive soils where a plate's vibration is less effective. Rollers scale the same vibrating principle up to a wide drum for covering large open areas efficiently.
When the wrong compactor type costs you time
Using a plate compactor in a narrow trench, or a rammer across a large open area, both work against the tool's design. A rammer in an open area takes far longer per square metre than a plate compactor built for that job, and a plate compactor simply won't fit in many trenches. Matching the tool to the space and soil type saves real time on site.
Limitations and alternatives
- Weight and impact force figures are manufacturer-rated maximums; always confirm compaction requirements (e.g. engineering specifications for footings) rather than relying on general guidance alone.
- Reversible plate compactors cost more than forward-only models but save time on jobs requiring back-and-forth passes.
- For very large-scale civil work beyond Riequip's roller range, additional options may be worth exploring with your project engineer.
Supporting evidence
- Compactor models, mechanisms, specifications and pricing referenced in this guide are drawn from Riequip's current range at riequip.co.nz/collections/plate-compactors, and the Alto CNR70 product page confirmed the percussive/rammer mechanism and impact force specifications directly.
- Confirm exact requirements for your situation with a Riequip specialist before purchasing, as prices, specifications and stock availability are subject to change.
Frequently asked questions
- What is the difference between a plate compactor and a rammer?
- A plate compactor uses a vibrating plate suited to granular soils, gravel and asphalt in open areas. A rammer uses a percussive, reciprocating shoe that delivers concentrated impact force, suited to cohesive or mixed soils in narrow trenches and confined spaces a plate compactor can't reach.
- Is a trench compactor the same as a rammer?
- Yes. Riequip's trench compactor range uses the same percussive, jumping-jack mechanism as what's commonly called a rammer in the trade; it's the same product type sold under a different name.
- When should I use a roller instead of a plate compactor?
- Rollers suit larger open areas such as road base and car parks, where their wider drum covers more ground per pass than a plate compactor. For smaller or irregular areas, a plate compactor remains more practical.
- Do I need a forward or reversible plate compactor?
- Forward-only compactors suit smaller, straightforward jobs. Reversible models cost more but save time on larger jobs requiring repeated back-and-forth passes without repositioning the machine.