What Is the Best Paver Base Material?
Select aggregate by pavement system and material specification rather than a gravel nickname; compare dense grading, open grading and bedding roles.
The best base material is the aggregate specified for your pavement system, traffic and site. Conventional sand-set pavers commonly use a compacted dense-graded aggregate base. Permeable systems use coordinated open-graded layers. A supplier label such as “gravel,” “crusher run” or “paver base” is not enough to establish compatibility.
Order a defined material
Ask for the gradation and material specification, not just the largest stone size. A dense-graded crushed aggregate contains a distribution of particle sizes, including controlled fines, to form a compacted layer. “Crushed stone” describes particle origin and shape; it does not alone say whether the blend is dense-graded or open-graded.
ASTM D2940 concerns graded aggregate material for bases and subbases. It is a material reference, not a statement that any product carrying that label is suitable at any depth on any soil. Project specifications may use applicable state or local aggregate requirements instead.
Distinguish the layer roles
| Material or system | What to verify | Frequent purchasing mistake |
|---|---|---|
| Dense-graded aggregate | Grading, fines, durability and specified compaction | Treating all quarry blends as identical |
| Open-graded angular aggregate | Layer gradation and compatibility with bedding, subgrade and drainage | Swapping only the base while keeping an incompatible bedding layer |
| Bedding sand | Sand-set system requirements and material quality | Using it to replace missing structural aggregate |
| Decorative gravel | Structural suitability, grading and compaction behavior | Assuming landscape appearance establishes pavement performance |
| Proprietary panels | Complete manufacturer assembly and application approval | Substituting a panel into an unrelated gravel detail |
Rounded decorative stones sold for landscaping are not automatically structural base. Their intended use, grading and behavior may differ from specified angular pavement aggregate. Conversely, an aggregate’s color or local nickname does not tell you its engineering properties.
Coordinate open-graded layers
CMHA’s permeable pavement construction guidance describes open-graded bedding, base and reservoir layers as an assembly. Those layers provide structural support and water storage or movement. The system also needs appropriate joints, subgrade treatment, outlet conditions and any designed underdrain or liner.
An open-graded base underneath conventional pavers does not by itself create a permeable pavement. Small bedding particles can migrate into larger voids if adjacent gradations are incompatible. Use a published complete detail rather than mixing materials from separate installation methods; the grading comparison explains this choice.
Questions for a supplier or installer
- What specification and gradation does the proposed material meet?
- Is it the specified base, bedding or drainage layer?
- What compaction procedure and equipment fit this assembly?
- How will water leave the base and how are fine particles kept from migrating?
- If sold by weight, what bulk-density condition does the supplier’s conversion describe?
Do not approve a material merely because a quantity calculator can estimate its volume. Resolve base depth and drainage alongside material selection.
After the material and compacted depth are specified, use the Paver Base Calculator to estimate cubic yards. Obtain density from the supplier if you need a tonnage order.
Sources and scope
- ASTM InternationalStandard Specification for Graded Aggregate Material for Bases or Subbases for Highways or Airports
Graded aggregate material specification. Does not establish a universal base depth or density.
- CMHACMHA PAV-TEC-002 (formerly Tech Spec 2 / Tech Note 2): Construction of Interlocking Concrete Pavements
Conventional interlocking concrete pavement construction; scoped base minimums and nominal uncompacted bedding guidance.
- CMHAConstruction of Permeable Interlocking Concrete Pavement Systems — PAV-TEC-018
Open-graded bedding, base and reservoir construction in permeable systems; not a substitute conventional sand-set detail.
Material specifications, construction guidance and product instructions have different scopes. Example inputs demonstrate calculations; they are not project defaults.