Floating vs Glue-Down vs Nail-Down: Which Timber Floor Installation Is Best?

Quick answer: On a Perth concrete slab, glue-down (direct stick) is usually the best way to lay engineered timber. It feels solid, sounds quiet and adds little height. Floating suits hybrid, laminate and some engineered boards, and it's quicker and cheaper. Nail-down is the traditional method for solid boards over timber joists or plywood, common in older homes with raised floors.

Two people can buy exactly the same engineered oak board and end up with floors that feel completely different. One sounds solid and quiet. The other clicks and sounds a bit hollow. The difference is usually the installation method, not the timber.

At Nulook Timber Flooring, we get asked about floating vs glue-down flooring on most quotes, especially when two installers have recommended different things. This guide explains how each method works, what it's good at, where it falls short, and which one suits your home.

The Three Methods at a Glance

	Floating	Glue-down (direct stick)	Nail-down
How it works	Boards lock together and rest on an underlay, not fixed to the subfloor	Boards glued directly to the slab or subfloor with flexible adhesive	Boards nailed through the tongue into joists, plywood or battens
Best subfloor	Concrete, existing flat floors	Concrete slab, plywood, particleboard	Timber joists, plywood, battens
Feel and sound	Slightly softer, can sound hollow	Solid and quiet	Solid, with a traditional "give"
Height added	Board + underlay (about 8–17 mm)	Board + adhesive (about 14–21 mm)	Board thickness (plus ply or battens on slabs)
Speed	Fastest	Medium	Slowest
Labour cost (engineered)	About $35–$55 per m²	About $55–$80 per m²	Varies; higher on slabs because ply or battens are needed
Can boards be lifted later?	Yes, fairly easily	No, not without damage	Partly
Typical products	Hybrid, laminate, click engineered	Engineered timber, some solid	Solid tongue-and-groove, thick engineered

Labour ranges from The Flooring Guys' 2026 engineered timber price guide.

Floating Floors

How a floating floor works

A floating floor isn't fixed to anything. The boards join to each other, usually with a click-lock profile along the edges, and the whole floor sits as one big mat on top of an underlay. On a concrete slab, a moisture barrier goes underneath, usually 200 µm polyethylene film with taped joins.

Because the floor isn't held down, it moves as one piece when temperature and humidity change. That's why floating floors need clear expansion gaps around every wall, cabinet and doorway, hidden under skirting or scotia. Long runs and L-shaped rooms often need expansion joints and trims in doorways too.

Where floating works well

• Hybrid and laminate. These are always floated.
• Apartments. An acoustic underlay under a floating floor helps meet strata noise rules.
• Quick installs. No glue to cure, so you can walk on it straight away.
• Slabs with slight moisture. With a proper barrier, floating copes better than glue-down.
• Future flexibility. Boards can be lifted and some can be reused.

The downsides

• Sound. Floating floors can sound slightly hollow or "clicky" underfoot, especially if the slab wasn't levelled properly.
• Flatness. They need a flat subfloor. Dips make the boards flex, and over time click joints can fail.
• Feel. Some people notice a subtle softness, especially with thicker underlays.
• Heavy furniture. Kitchen islands and heavy built-ins shouldn't sit on a floating floor, because they pin it and stop it moving.

Glue-Down (Direct Stick) Floors

How glue-down works

The slab is ground clean, tested for moisture and levelled. Then a flexible flooring adhesive is spread across the slab with a notched trowel, and each board is pressed into it. The adhesive stays slightly elastic, so the timber can move a little through the seasons without cracking the bond. Many modern adhesives also act as a moisture barrier.

We use professional adhesive systems from Sika, Uzin, Wakol and Bona, matched to the board manufacturer's recommendations so the product warranty stays intact.

Where glue-down works well

• Engineered timber on concrete slabs. This is most Perth homes, since most are double brick on a slab.
• Big open-plan areas. Glued floors don't need the same expansion joints as long floating runs.
• Quiet, solid feel. It's the closest thing to solid timber underfoot.
• Low height. Useful where the new floor meets tiled bathrooms or sliding door tracks.
• Heavy furniture and kitchen islands. The floor is held in place, so weight isn't a problem.

The downsides

• Prep is essential. Glue won't hold on old tile adhesive, dust or a damp slab. Skipped prep is the main cause of glue-down failures.
• Cost. Adhesive and extra labour add roughly $20–$25 per m² compared with floating.
• Hard to reverse. Replacing a board means cutting it out.
• Cure time. The adhesive needs time before heavy furniture goes back, usually a day or two.

Our guide to installing timber flooring over concrete covers grinding, moisture testing and levelling in detail.

Nail-Down Floors

How nail-down works

This is the traditional way to lay solid timber. Tongue-and-groove boards are nailed through the tongue at an angle (called secret nailing) so the nail heads are hidden by the next board. Thicker boards may also be face-nailed, with the nails punched below the surface and filled.

The boards are nailed to one of three things:

• Timber joists, in older homes with raised floors
• Plywood or particleboard sheeting, in newer timber-framed floors
• Battens or plywood fixed to a concrete slab, when solid boards are wanted on a slab

In practice, many installers glue and secret-nail boards to a plywood subfloor for extra hold.

Where nail-down works well

• Older Perth homes on stumps. Many 1920s–1960s homes have raised timber floors on joists, often with original Jarrah boards.
• Solid tongue-and-groove boards. This is what nailing was designed for.
• Matching an existing raised floor. Keeping the same system makes the join between old and new easier.

The downsides

• On a slab, it needs a timber layer first. Plywood or battens add height (often 15–25 mm) and cost.
• Slowest to install. Every board is fixed individually.
• Squeaks over time, if the subfloor or nailing isn't right.

Which Method Suits Your Home?

Your situation	Usually best
Engineered timber on a concrete slab (most Perth homes)	Glue-down
Hybrid or laminate anywhere	Floating
Apartment with strata acoustic rules	Floating with an approved acoustic underlay, or glue-down with an acoustic mat, depending on the by-laws
Solid boards on a slab	Glue-down direct, or ply glued to the slab then boards secret-nailed
Older home with raised floor on joists	Nail-down (secret nailed)
Slab with moisture issues	Floating over a heavy moisture barrier, or glue-down with a moisture-barrier primer
Underfloor heating	Depends on the product; check the manufacturer's rules
Kitchen with a heavy island bench	Glue-down, or floating with the island installed first
Tight budget, fast turnaround	Floating

If you're still choosing between product types, our engineered vs hybrid flooring comparison helps narrow it down.

Old Jarrah Floors on Joists: Restore or Replace?

If you've pulled up carpet in an older Perth home and found Jarrah boards nailed to joists, you have options. Those boards are often in far better shape than they look. A full sand and recoat can bring them back for a fraction of the cost of a new floor. Our floor sanding and polishing guide explains what's involved.

If some boards are damaged, matching Jarrah can be sourced and secret-nailed in. If the floor is too far gone, a new solid or engineered floor can be laid over the existing boards (once they're flat and firmly fixed) or over new plywood. Either way, the nail-down system under your house stays, and the new floor is fixed to suit it.

Apartments and Acoustic Rules

In strata buildings, the installation method is often decided by the by-laws. Many require hard floors to meet a minimum sound rating, which usually means a floating floor on an approved acoustic underlay, or a glue-down floor over an acoustic mat. The ATFA's note on installation over acoustic underlays explains how these systems affect timber floors. Check your strata's requirements, in writing, before you choose a product.

What About Underfloor Heating?

Underfloor heating isn't common in Perth, but it's turning up in more new builds and Hills renovations. Engineered timber usually works over it, either glued or floated, depending on the manufacturer's instructions. Most set a maximum floor surface temperature (often around 27°C) and ask for the heating to be run up slowly at the start of each season. Solid timber and nail-down systems are less suitable, because solid boards move more with heat. Check both the flooring and the heating manufacturer's rules before you decide.

"My Installer Wants to Float My Engineered Floor. Is That Wrong?"

Not necessarily. Plenty of click-system engineered boards are designed to float, and floating can be the right call in apartments or over slabs with moisture concerns. But on a well-prepared Perth slab, in a family home, we usually recommend gluing engineered timber for the feel and sound.

Ask your installer why they've chosen their method, and whether the board manufacturer approves it. If the answer is "it's quicker", that's not really a reason. Our guide on how to choose a timber flooring installer in Perth lists other questions to ask.

Does the Method Affect the Warranty?

Yes. Every flooring manufacturer publishes installation instructions, and the warranty depends on following them. Some engineered boards can only be glued. Some are approved for floating only on certain underlays. Hybrid must float. Using an adhesive the manufacturer hasn't approved, or skipping the moisture barrier, can void the product warranty. The WoodSolutions Timber Flooring Technical Design Guide covers the accepted methods for Australian timber floors if you want the technical detail.

What About Cost?

For engineered timber, the method changes labour more than materials:

• Floating: about $35–$55 per m² labour, plus underlay
• Glue-down: about $55–$80 per m² labour, including adhesive
• Nail-down on a slab: the highest, because plywood or battens go down first

On a 70 m² area, glue-down might add $1,400–$1,750 over floating. For a floor you'll live on for 20+ years, most of our customers think the quieter, more solid feel is worth it. Our engineered timber flooring cost guide has full price breakdowns.

The Short Version

If you only remember one thing: the right method depends on what's underneath and what you're laying. On a typical Perth slab with engineered timber, glue it. For hybrid, float it. For solid boards over joists, nail it. And whichever method you choose, the prep underneath matters more than the method itself.

Talk It Through on Site

The right method depends on your subfloor, your product and how you live. Nulook Timber Flooring checks all three at a free on-site measure, tests your slab for moisture, and recommends the method that suits your home, with the reasons in writing. See our engineered timber flooring service, then book your free measure or call 0405 821 884.

Frequently Asked Questions

What is a floating timber floor?

A floating timber floor is one where the boards lock together and sit on an underlay without being glued or nailed to the subfloor. The whole floor moves as one piece, so it needs expansion gaps around the edges.

Is it better to glue or float engineered flooring?

On a flat, dry concrete slab, gluing engineered flooring usually gives a more solid, quieter floor. Floating is faster and cheaper and suits apartments or slabs with moisture concerns. Always follow the manufacturer's approved methods.

Why does my floating floor sound hollow?

A hollow sound usually means the subfloor wasn't levelled properly, leaving small gaps under the boards. A thin or poor-quality underlay can also make it worse. Proper levelling before installation prevents it.

Can you nail timber flooring to a concrete slab?

Not directly. Timber is nailed to plywood or battens that have first been glued and fixed to the slab. Most engineered floors on slabs are glued directly instead.

Is glue-down flooring more expensive than floating?

Yes, slightly. Glue-down labour for engineered timber typically costs about $55 to $80 per square metre, compared with $35 to $55 for floating. The extra covers adhesive and slower installation.

Can hybrid flooring be glued down?

Generally no. Hybrid flooring is designed to be floated. Gluing it down can void the warranty, except on stairs, where treads are glued and finished with matching nosings.

Which installation method is quietest?

Glue-down is usually the quietest on a concrete slab because the boards are bonded to the subfloor. Floating floors can sound more hollow unless the slab is flat and a good underlay is used.

Can you put a kitchen island on a floating floor?

It's best not to. Heavy islands pin a floating floor and stop it moving, which can cause buckling or gaps. Install the island first and float around it, or glue the floor down.

What is secret nailing?

Secret nailing is when nails are driven at an angle through the tongue of each board into joists or plywood, so the next board hides the nail. It's the traditional method for laying solid tongue-and-groove timber.

Can a glued-down timber floor be removed later?

Yes, but it's hard work. Boards have to be cut and pried up, and the adhesive ground off the slab before a new floor goes down. Floating floors are much easier to lift.