Choosing SPC flooring by thickness sounds simple at first. Pick the thickest board your budget allows, and the decision appears to be made. In practice, it is more nuanced than that.
A 5.7mm plank, a 6.5mm plank, and an 8mm plank can all be excellent choices, but they suit different rooms, expectations, and subfloor conditions. The best result comes from matching the board to how the space will be used, the condition of the floor beneath it, the required floor build-up, and the feel you want underfoot.
Why Thickness Matters More Than Many People Expect
SPC flooring is valued for its water resistance, ease of care, rigid construction, and practical everyday durability. Its core can provide good dimensional stability under normal indoor conditions, which is one reason SPC is popular in homes, apartments, retail spaces, and light commercial settings across New Zealand.
However, SPC flooring should not be treated as unaffected by site conditions. Strong sunlight, heat build-up, poor expansion allowance, substrate moisture, and incorrect installation can still affect performance.
Thickness affects several practical things at once. It can influence how solid the floor feels, how much walking sound is reduced, how substantial the floor feels underfoot, and how it transitions to other floor finishes. Thickness also affects door clearances, stair details, and the total floor build-up.
That said, thickness is not the only marker of quality. A thinner SPC board with a strong wear layer, a well-made core, a reliable click system, and a suitable backing can outperform a thicker board of weaker construction. It is best to treat thickness as one part of the decision, not the whole decision.
After weighing up thickness, most buyers are really deciding between a few key outcomes:
quieter rooms
a firmer feel underfoot
better comfort during daily use
easier renovation planning
cleaner transitions to adjoining floors
stronger value for money
A Quick Comparison of 5.7mm, 6.5mm, and 8mm
These three thicknesses sit in a very useful part of the market. None of them is too thin for serious consideration, and none should be chosen by thickness alone. The differences are meaningful, especially once installation conditions and room use are taken into account.
| Thickness | Best Suited To | Feel Underfoot | Sound Performance | Subfloor Requirement | Budget Impact |
|---|---|---|---|---|---|
| 5.7mm | Standard residential rooms, budget-conscious renovations | Firm | Good | Requires a flat, well-prepared subfloor | Lowest of the three |
| 6.5mm | Most homes, family living areas, balanced upgrades | More solid | Better | Requires a flat, stable subfloor; may feel more settled over very minor variation | Mid-range |
| 8mm | Premium residential areas, comfort-focused projects, stronger acoustic expectations | Most substantial | Strongest of the three | Still requires proper preparation; does not correct poor subfloor conditions | Highest |
Important: A thicker SPC plank may feel more substantial, but it is not a substitute for proper subfloor preparation. The base still needs to be flat, dry, clean, and stable.
When 5.7mm Is the Right Call
A 5.7mm SPC floor is often a sensible choice for bedrooms, home offices, rental properties, and renovations where floor height matters. If you need to keep transitions tidy or avoid trimming doors, this thickness can be very convenient.
It also appeals to buyers who want the practical benefits of SPC without paying for extra board mass they may not need. In a well-prepared room with a flat and stable subfloor, a 5.7mm SPC floor can perform very well.
Many modern products in this thickness still offer attractive timber-look finishes, reliable click systems, and suitable wear resistance for normal residential use.
The main point to keep in mind is that 5.7mm has less margin for installation error. If the slab or timber subfloor has noticeable dips, ridges, movement, or moisture issues, the floor may feel less substantial than a thicker option, and the locking system may be placed under stress.
A 5.7mm board usually works best when these conditions apply:
Subfloor condition: flat, dry, stable, and properly prepared
Project priority: cost control without giving up visual appeal
Room type: lower to moderate traffic areas
Build-up limits: tight floor heights or tricky transitions
Expectation: practical performance rather than a premium underfoot feel
Why 6.5mm Often Feels Like the Sweet Spot
For many homes, 6.5mm SPC flooring sits in the middle of comfort, durability, and price. It is thick enough to feel more grounded underfoot than thinner options, yet still practical for most renovations.
This thickness is especially appealing in open-plan living spaces, hallways, kitchens, and family areas where daily foot traffic is steady. It tends to offer a more confident step, better acoustic feel, and a more substantial impression underfoot.
A 6.5mm board can also be a smart choice when the floor needs to carry visual weight. Wider or longer planks often feel more convincing when the board has enough body to support that premium look.
If the aim is to achieve a polished finish without moving into the highest price bracket, 6.5mm is often the strongest all-rounder.
There may also be a practical installation benefit. Installers often appreciate a board that has a little more rigidity during laying, especially in larger rooms. However, this should not be understood as permission to ignore subfloor preparation. Even 6.5mm SPC still needs a flat, dry, and stable base.
Where 8mm Makes the Biggest Difference
An 8mm SPC floor is usually chosen for comfort, acoustic control, and a more substantial feel. Step onto it, and the difference is often noticeable. The floor may feel quieter, denser, and more premium, especially in larger rooms where sound can travel.
This thickness may suit high-use family homes, upper-level rooms, apartments, media rooms, bedrooms, and spaces where a stronger sense of solidity is wanted.
In premium renovations, 8mm often earns its place because it changes the experience of the room, not just the specification sheet. The floor can feel calmer and more refined, which matters in main living zones and comfort-focused interiors.
However, there are trade-offs. Thicker boards usually cost more, can affect door clearances, and may create more noticeable transitions to adjoining finishes. In some projects, those floor-height issues may make 6.5mm the more practical choice.
Most importantly, 8mm SPC should not be treated as a solution for poor subfloor conditions. It may feel more substantial, but it still needs proper preparation. If the subfloor is uneven, damp, unstable, or moving, even an 8mm product can disappoint.
Thickness Is Only Half the Story
A thicker board is not automatically the better board.
The following specifications often matter just as much, and sometimes more:
Wear layer
Click system
Core quality
Surface texture
Attached backing
Slip resistance
Warranty terms
Installation requirements
The wear layer deserves close attention in busy homes and light commercial settings. This is the protective top layer that helps resist scratching, scuffing, and general wear. A strong wear layer may be more important than moving up one thickness category.
The attached backing also changes the result. Some SPC floors include an acoustic backing, which can improve sound control and walking comfort. A 6.5mm board with a quality attached backing may feel more refined than a thicker board with a basic construction.
Before making a final decision, check the specifications side by side:
Wear layer: suited to household traffic or heavier use
Core density: firm and stable construction
Surface finish: realistic grain, matte balance, and slip resistance
Backing layer: acoustic support and comfort
Click system: secure fit and installation reliability
Warranty terms: clear coverage for residential or commercial use
Installation guide: clear requirements for subfloor, expansion, temperature, and maintenance
The Subfloor Often Decides More Than the Sample Board
This is where many flooring choices are won or lost. A beautiful sample tells you very little about how the finished floor will behave over an uneven slab or a timber substrate with movement.
SPC flooring performs best when the base is flat, dry, clean, and stable. Thicker planks may feel more substantial over very minor variation, but they do not solve structural, moisture, or flatness problems.
If the subfloor is poor, even a premium product may not perform as expected.
In a renovation, it is wise to ask early questions about:
floor preparation
moisture testing
levelling compounds
door clearances
bathroom transitions
carpet transitions
exterior door thresholds
expansion allowance
These practical details often shape the thickness choice more than aesthetics do. One difficult threshold can be enough to change the specification across the whole project.
Matching the Thickness to the Room
Different rooms ask different things of a floor. A spare bedroom and a busy kitchen may sit within the same home, yet they place different demands on the surface.
If the project covers several spaces, consistency usually looks better than mixing multiple SPC thicknesses. Still, it helps to understand where each option tends to make sense.
Bedrooms and studies: 5.7mm or 6.5mm may be suitable where traffic is moderate, and the subfloor is properly prepared.
Family living zones: 6.5mm is often a strong balance of feel, cost, and everyday practicality.
Hallways and entrances: 6.5mm or 8mm may be considered where traffic is heavier, depending on product specification.
Apartments and upper floors: 8mm may help with underfoot feel and acoustic comfort, but the full flooring system should be checked.
Budget-focused rentals: 5.7mm or 6.5mm may be practical where value, stock availability, and easy maintenance are priorities.
A practical rule of thumb works well:
5.7mm: suitable when value and floor height are key concerns
6.5mm: a strong all-round choice for most homes and everyday use
8mm: best when comfort, sound control, and a premium feel are higher priorities
Sunlight, Heat, and Indoor Conditions Still Matter
SPC flooring is designed for normal indoor use, but it is not immune to environmental conditions.
Strong direct sunlight, heat build-up, very dark colours, large glazing, poor shading, and insufficient expansion allowance can increase the risk of movement, peaking, gapping, joint stress, or localised distortion.
Like other flooring products, SPC may also experience colour change or fading where areas receive different levels of sunlight over time.
For sun-exposed rooms, consider:
curtains or blinds
UV-filtering glass where practical
medium or lighter colours in high-heat areas
correct expansion allowance
manufacturer installation guidance
avoiding excessive heat build-up
This is especially important in rooms with large sliders, north-facing glazing, conservatories, or strong afternoon sun.
Supply Depth Matters More Than People Think
The right thickness is easier to choose when you can compare a wide range of colours, finishes, wear layers, attached backing options, and constructions side by side.
In New Zealand, access to a broad flooring range can make specification much more efficient, especially for builders, designers, and homeowners managing timelines.
FLOORCO, established in Auckland in 2015, supplies a wide range of SPC flooring, laminate flooring, engineered wood flooring, tiles, and related flooring accessories. With broad local stock availability, established supplier relationships, and a large Auckland warehouse, FLOORCO can help customers compare flooring options more efficiently and choose products that suit their project requirements.
The scale of available stock can also matter. A broad product range gives customers more room to compare colour, surface finish, wear layer, attached backing, thickness, plank size, and budget before making a decision.
When buyers can compare these details in one place, the decision becomes more precise and less dependent on thickness alone.
Final Thought
A good SPC flooring choice is rarely about choosing the thickest board on the shelf.
It is about choosing the board that fits the room, subfloor, traffic level, budget, floor height, acoustic expectation, and finish level.
For many homes, 6.5mm will provide the best balance. For sharper budgets or tight floor heights, 5.7mm can be a practical choice. For a more substantial feel and stronger acoustic comfort, 8mm may be worth considering.
The best result comes from combining the right thickness with the right product specification, correct subfloor preparation, and suitable installation conditions.
Editor: Terry Shi
The founder of FLOORCO with a strong industry background and substantial supply chain resources.
