Renovation vs new-build — timing your flooring decision
When to pick your floor in a renovation timeline, what arrives when, and the trades that need to be finished before the planks come out of the box.
A floor going into a renovation is not the same job as a floor going into a new build, even when the plank specification is identical. The subfloor is different, the climate of the building during installation is different, the access is different, and the trades around you are different. Understanding which of those differences matter most prevents the most common installation problems and decides the install method.
This article is written for specifiers, builders, and clients trying to understand why their flooring contractor is asking different questions about a renovation than a new build. The conversation can feel pedantic in the early phase, but the questions are the right ones to ask before the planks are ordered.
The subfloor question
In a new build, the subfloor is whatever the structural engineer specified — typically a concrete slab on ground, a suspended concrete slab on a steel deck, or a structural timber floor on joists. In all three cases the surface is known, the construction sequence is documented, and the moisture content is testable to a recognised protocol.
In a renovation, the subfloor is whatever the previous floor was bonded to, sometimes for decades. Old slab tiles, removed parquet, residual adhesive, glue residue from carpet underlay, plywood subfloors with unknown moisture history — all of this needs to be assessed before the new plank is even considered. Our subfloor preparation guide covers the assessment protocol in detail.
Levelling and flatness tolerances
For floating installations the industry tolerance is a maximum 3 mm deviation in 2 m; for glue-down it tightens to 2 mm. New-build slabs are usually within tolerance straight from the screed; renovation slabs are usually not. Self-levelling compounds are the most common remediation for renovation projects, sometimes across the entire floor area, sometimes in localised zones.
The levelling cost is the largest hidden line item in renovation quotes for engineered timber. A flooring contractor who quotes without inspecting the existing slab is quoting a floor; with inspection, they are quoting a project.
Moisture and acclimatisation
New-build slabs are often still releasing construction moisture months after they are poured. A six-week-old slab is rarely dry enough for a glue-down install, and even floating engineered timber may be vulnerable to vapour rising through an under-cured slab. The standard test is in-situ relative humidity probes installed in line with ASTM F2170, with verification before installation.
Renovation slabs, by contrast, are usually old enough to be dimensionally stable but may have moisture entering from groundwater, leaking plumbing, or a damp-proof membrane that was never installed. The renovation moisture test is therefore a different question — not "is the slab dry yet?" but "is the slab going to stay dry?" The 48-hour rule article covers plank acclimatisation in both contexts.
Install method choice
Renovations more often favour floating installation. The subfloor is rarely perfect, the acoustic underlay forgives minor variation, and reversibility is sometimes valuable. New builds with engineered timber more often favour glue-down — the slab is flat, the construction moisture is testable, and the acoustic and underfoot benefits of a bonded install are worth the additional labour cost.
For wider context on installation method selection, our floating vs glue-down guide covers the trade-offs. The technical data hub includes the installation specifications for each of our ranges.
Programme and trades coordination
In a new build, the flooring contractor typically arrives after the major trades have finished but before final paintwork, with kitchens and joinery installed over the new floor. In a renovation, the sequence is rarely so clean — kitchens may be retained, joinery may need to be removed and refitted, and the flooring contractor will be working around existing skirtings, architraves, and door frames.
Heritage renovations bring their own additional layer of complexity. See the heritage and conservation article for our approach. The Australasian Timber Flooring Association publishes installation protocols that apply across both contexts, and the Standards Australia catalogue covers the relevant AS standards for in-situ moisture testing.
Climate management during the install
A new-build install often happens before the HVAC is commissioned and balanced. The plank then acclimatises to a climate that does not yet exist, which is a recipe for movement after handover. The right sequence is to commission the heating and cooling, run it for at least a week, then bring the plank into the conditioned space — not the other way around. Renovation installs typically have a working HVAC system from day one, which is one of the underrated advantages of the project type, and it shortens the acclimatisation period the plank actually needs.
