November 5, 2026
An expansion gap is the small space left between a floating floor and the walls so the floor can move. Timber, laminate and hybrid boards expand and contract with temperature and humidity, and without that gap a floating floor can lift, peak or buckle. Here is how expansion gaps in floating floors work, how they are hidden and where else the floor needs room.
A floating floor is not glued or nailed to the subfloor. The boards join to each other and the whole floor rests on its underlay as one piece. The expansion gap is the space around its edges, against walls, door frames, cabinets, pipes and anything else fixed in place. Every installation guide quoted below says the floor should have no direct contact with walls, cabinets or fixtures.
Timber takes up moisture from the air in humid weather and gives it back when the air is dry, so it swells and shrinks a little through the year. Engineered timber and laminate have wood-based layers and respond in a similar way. Hybrid boards are more stable with moisture, but they still expand in heat and contract as they cool. Across a whole room those small changes add up, so the gap runs right around the perimeter.
There is no single number. Each range’s installation guide sets its own gap, and some ask for more in humid areas or on long runs. Here is what the guides on our product pages say for a floating installation:
| Range | Floor type | Perimeter gap in its guide | Room breaks in its guide |
|---|---|---|---|
| Royal 6.5mm Premium and Royal Hybrid Pro 9mm | Hybrid | 10mm (the warranty refers to more than 10mm) | Separate at doorways; no area over 50 square metres |
| Royal Procore Laminate | Laminate | 10 to 12mm | Separate at doorways; no area over 60 square metres; transition trims beyond 12m long or 8m wide |
| RoyalStep Laminate 12mm | Laminate | 10 to 12mm minimum; 12 to 15mm in high humidity or longer runs | Separate at doorways; no area over 60 square metres |
| Royal AquaCore Oak | Engineered timber, click-lock | At least 10mm; 10 to 12mm generally recommended | Separate at doorways; no area over 70 square metres |
| Royal 15/4MM Oak | Engineered timber, tongue and groove | Minimum 12mm | Separate at doorways; no area over 60 square metres; sections up to 8m wide and 12m long in moderate humidity |
If the range you like has no guide on its product page, ask us for it. Guides are updated, so check the current version. Book a free measure and quote and we will measure the runs, check the subfloor and test it for moisture free of charge.
When one floor runs through several rooms, movement in one room pushes on the next, and the narrow doorway is where it binds. That is why the guides above ask for large multi-room installations to be separated at doorways, with the gap covered by a trim, and set a maximum area for each section. The guides also ask installers to check that doors still open and close with at least 1cm of clearance once the floor is down.
A floating floor cannot have anything fixed on top of it. The Royal 15/4MM Oak guide says not to install cabinets, kitchen islands or other fixtures on top of floating floors, and to keep an expansion gap where the floor meets cabinetry, columns and pipes. The Royal hybrid guide says island benches require the floor to be cut in. In a renovation, that means the kitchen goes in first and the floor is laid around it.
Humid summers, wet spells and air conditioning change indoor humidity through the year, so floors here keep moving. The Royal 15/4MM Oak guide says the size of each floating section may need to be assessed individually in areas of higher humidity, near waterways, on the coast or in more extreme climates. It also suggests a larger gap where humidity varies a lot. The RoyalStep guide recommends 12 to 15mm in high humidity. The AquaCore Oak and 15/4MM Oak guides also call for protecting the floor from extremes with curtains, blinds, awnings, window tinting and humidity control. Our guide to flooring for Queensland homes has more on choosing for heat and humidity.
We give advice to DIY installers, so ask us before you start. Read your range’s installation guide in full, use spacers to hold the gap, remove them before the skirting or scotia goes on, and keep the gap at every pipe, door frame and cabinet. Product warranties come from the manufacturer and depend on installing to the guide. Our DIY flooring advice page and DIY vs professional installation guide can help you decide whether to do it yourself or book professional installation.
For more on each floor type, see our guides to floating timber floors, laminate flooring installation and hybrid flooring installation, or browse our timber, laminate and hybrid flooring.
It is a small space left between a floating floor and the walls, cabinets, pipes and other fixed objects. It gives the floor room to expand and contract with temperature and humidity, and it is usually hidden by skirting, scotia or trims.
It depends on the range, so always follow its installation guide. For example, the guide for Royal 6.5mm Premium and Royal Hybrid Pro 9mm asks for 10mm, Royal Procore Laminate’s guide asks for 10 to 12mm, and Royal 15/4MM Oak’s guide asks for a minimum of 12mm when floated.
No. Skirting and scotia are fixed to the wall and cover the gap without being fixed to the floor. If they are fixed into the floor, they pin it, and it can lift or peak.
Often, yes. The installation guides for the ranges in this article say large multi-room installations are separated at doorways, with the gap covered by a trim, and they set a maximum area for each section.
No. Islands and fixed cabinets go in first and the floating floor is laid around them, with an expansion gap where the floor meets the cabinetry.
With over 20 years of experience, our installation team lays floating floors to each range’s guide, and Royal Floors gives a 2 year installation warranty on our installation work. Visit us in Penrith, Campbelltown, Hornsby or Logan, book a free measure and quote, or call 1300 980 501.
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