Common Paving Mistakes to Avoid

Getting paving wrong is expensive. Whether it’s a driveway, patio, pool surrounds, or a garden path, paving mistakes often don’t show up immediately: they creep in over months and years as shifting, cracking, pooling water, and crumbling edges start to reveal what went wrong beneath the surface.

Here in Perth, we deal with specific conditions that make proper installation even more important: sandy coastal soils in the western suburbs, clay-heavy ground in the hills and outer corridors, scorching summer heat that bakes sealants and stresses mortar joints, and heavy winter rain events that can expose poor drainage in a matter of hours.

If you’re planning a paving project, or trying to understand what went wrong with an existing one, here are the eight most common paving mistakes we see, and how to avoid them.

1. Poor Foundation Preparation

This is the single most common cause of paving failure, and it’s entirely avoidable.

The base layer is what everything sits on. If it’s too shallow, poorly compacted, or built on unstable ground, the pavers above it will shift, dip, and crack, no matter how good the stones themselves are.

What the right foundation looks like:

• Paths and pedestrian areas: excavate to at least 150mm to 200mm (15cm to 20cm) and fill with compacted road base
• Driveways: excavate to 250mm to 300mm minimum to handle vehicle loads
• Every layer of base material must be compacted before the next is added: don’t skip this step

In Perth, sandy soils are particularly unforgiving. They may feel stable at first, but shift under load or when wet. Areas near the coast or on filled ground need extra attention. Clay-heavy areas in the eastern and southern suburbs can shrink and swell seasonally, so the base must be deep enough to account for ground movement.

A common shortcut is not extending the base material far enough beyond the paved edge: the base should extend at least 100mm past the outer edge of the restraint for proper support.

2. Inadequate Drainage Planning

Water is the enemy of pavement. If it has nowhere to go, it will find its way under, through, and around your pavers, eroding the base, washing out bedding sand, and eventually destabilising the whole surface.

What adequate drainage looks like:

• All paved surfaces need a minimum fall of 1:60 (approximately 16mm per metre) sloping away from buildings and structures
• A slope of 1 to 2% is the standard target for patios and paths
• Water should always be directed toward a designated drainage channel, garden bed, or drain, not toward fences, walls, or neighbours

In Perth’s climate, this matters year-round. Summer storms can be intense and short-lived, depositing heavy rainfall quickly. Poor grading means that water pools on the surface or, worse, sits beneath it, slowly undermining the base.

If your site has natural low points, a drainage solution such as a slotted drain or agricultural drain under the base may be needed before a single paver goes down.

3. Skipping Edge Restraints

This mistake is so common and so costly that it’s worth explaining in detail.

Edge restraints are the physical barriers installed along the perimeter of any paved surface. Their job is to hold everything in.

Without them, the outward pressure of foot traffic, vehicle weight, and soil movement causes the edge pavers to gradually spread apart.

Once the edge starts to go, the sand bedding loses containment, washes out, and the structural failure works its way inward.

What happens without edge restraints:

• Perimeter pavers spread, creating widening joints
• Bedding sand washes out through gaps, especially after rain
• Edge pavers begin to settle unevenly
• The problem spreads inward over one to two wet seasons

Edge restraints should run along the entire perimeter, not just problem spots. They should be installed before final compaction, and must sit directly on the compacted base (not just the bedding sand) for proper anchoring.

In Perth’s sandy-soil environments, this is especially critical. Sand-based ground provides very little natural lateral resistance, which means unrestrained paving will migrate faster than it would in clay-heavy soils.

4. Incorrect Sand Bedding

The bedding layer (the thin layer of sand between the compacted base and the pavers) sounds simple, but it’s easy to get wrong in ways that cause long-term problems.

Key rules for bedding sand:

• The bedding layer should be a consistent 25mm (approximately 1 inch), no more
• A thicker layer doesn’t give more flexibility; it creates instability and uneven settling over time
• Crusher dust is not an appropriate substitute for proper coarse bedding sand and is not recommended
• Do not compact the bedding layer before laying pavers, the pavers go on screeded (levelled) sand, and the final compaction happens after the pavers are in place

Screeding must be done carefully to ensure an even surface. Uneven bedding produces dips and high spots that worsen over time as the sand compresses unevenly under load.

5. Poorly Mixed or Applied Mortar

For mortar-set paving (as opposed to sand-set), the mortar quality is critical. A weak or incorrectly mixed mortar leads to loose pavers, hollow spots (known as “drummy” pavers), and staining on the paver surface.

Common mortar mistakes:

• Rushing the mixing process, resulting in inconsistent consistency
• Using too much water, which weakens the bond strength
• Using a standard cement-and-sand mix for large-format or engineered stone pavers, without mortar additives
• Not applying a wet cement paste to the back of the paver before bedding (required for proper adhesion with sandstone and natural stone)

Mortar additives significantly improve workability, adhesion, and long-term flexibility, particularly for large-format pavers and non-standard stone types. They’re not optional on premium installations.

Mortar spills on paver surfaces should be cleaned immediately. Once dry, mortar stains can be extremely difficult to remove without acid washing.

6. Wrong Gap Spacing Between Pavers

Gaps between pavers aren’t just aesthetic, they’re structural. Getting the spacing wrong causes real problems.

The right approach:

• Most pavers should have a gap of at least 2mm to 4mm between them (the AI overview cites 3mm as ideal)
• Pavers laid too tight, less than 2mm, will chip at the edges under load, as there’s no room to accommodate minor movement and the natural growth that clay pavers experience over time
• Gaps that are too wide look poor, allow weed growth, and reduce the structural interlock that holds the surface together

Joint sand should be swept in after installation and compaction to fill gaps and lock pavers in place.

On areas exposed to channelled water flow (such as near downpipes), a stabilised jointing sand or cement-blended joint sand is worth considering to resist washout.

7. Skipping Sealing and Maintenance

A freshly laid paving job looks great. Without sealing and basic maintenance, it won’t look that way for long, and you’ll end up with structural problems, not just cosmetic ones.

Why sealing matters in Perth specifically:

• Perth’s UV intensity is among the highest in Australia. Unsealed pavers fade and degrade significantly faster than sealed ones
• Unsealed joints allow weed seed germination, particularly in our warm, humid winters
• Stains from iron, tannins, algae, and organic matter are much easier to prevent than remove

What good maintenance looks like:

• Seal pavers with a water-based acrylic sealant once laid (honed pavers must be sealed immediately)
• Re-seal every 2 to 4 years depending on traffic and sun exposure
• Inspect joints annually and re-sand where erosion has occurred
• Address any cracked or loose pavers early: small problems become expensive ones quickly

Early intervention is always cheaper than reinstatement. A cracked paver that’s caught in the first season costs a fraction of what you’ll pay to relay a section that’s been shifting for two years.

8. Lack of Planning Before the Project Starts

This one wraps around everything above. Most costly paving mistakes are made before a single paver is laid: in the planning (or lack of planning) stage.

A proper plan should include:

• The dimensions and layout of the paved area
• The intended use (pedestrian only, vehicle access, pool surrounds, etc.): this determines base depth and paver thickness requirements
• Where water will drain to, and how
• Where expansion joints are needed (at changes in direction, every 3 to 3.5 metres on large areas, and wherever the paving meets a wall or building)
• What type of bedding and mortar method is appropriate for the chosen paver material

For large paving projects, getting a second opinion or professional quote before starting is not a sign of uncertainty: it’s good project management. Understanding what’s involved in a proper installation helps you make sense of why quotes vary, and what corners a cheap quote might be cutting.

Thinking About Paving in Perth?

Perth Landscape Guys install paving across Perth’s northern, southern, and western suburbs, from travertine pool surrounds to brick driveways, limestone edging, and full backyard transformations.

If you want paving done the first time properly, get in touch for a free quote.

Related Services:

• Paving Perth
• Travertine Pavers Perth
• Backyard Landscaping

Mike Tuhaka

Mike Tuhaka runs Perth Landscape Guys. He and his team design and build outdoor spaces right across Perth, from Currambine down to Mandurah, including paving, decking, retaining walls, artificial grass, lawn and reticulation. They are preferred installers for Freo Stone, Eco Stone and Remastone, and have worked on commercial projects for Murdoch University and Parsons Group. What customers mention most is Mike’s honest advice and the regular updates from the first plan to the final clean up.