A 160×320cm slab looks identical to a 60×120cm tile in a rendering. On-site, it isn't the same job at all.
The delivery truck, the crew, the adhesive, the trowel technique- none of it stays the same once a specification moves into a genuinely large format. The 120×280cm and 160×320cm sizes make a floor or a feature wall look uninterrupted, almost seamless. The problem is that most installation teams have built their instincts around standard-format tile, and a fair number of those instincts stop working the moment the slab gets this big. This is written for teams working through a large-format Grifine order: the site supervisor, the installer, the project manager signing off the mockup, not someone choosing a finish for a living room.
The size on the specification sheet changes the job
A 60×120cm tile is forgiving in ways nobody usually notices, because the format is small enough to absorb minor mistakes. Two people can carry it. A slightly uneven substrate barely shows. Standard tile adhesive, applied with reasonable trowel technique, holds it in place without much drama.
None of that holds at 120×280cm, and even less at 160×320cm. A slab that size is heavy, thin relative to its span, and genuinely brittle under the wrong kind of load, not fragile in normal use once it's installed, but vulnerable during the window between the truck and the finished floor. Specifying the size is the easy part. Planning for what that size requires on-site is where projects actually succeed or fail.
A slab this size can't be carried like a tile
Large-format slabs get carried vertically, tilted at roughly 80 to 85 degrees, never flat. Carrying a 160×320cm slab horizontally puts its own weight to work against it; the unsupported span flexes under gravity alone, and a hairline crack from that flex often doesn't show until the slab is already installed and under load. A-frame or T-frame stands hold slabs upright and slightly tilted during storage and transport, and multi-cup vacuum lifters do the actual lifting. Manual carrying by the edges, the instinct for a standard tile, is exactly the wrong instinct here.
Crew size follows slab weight and thickness rather than habit; a job that a two-person team handled comfortably at 60×120cm usually needs more hands and mechanical support once the format moves into Grifine's 120×280cm and 160×320cm range. Confirming the exact crew size and equipment with the installation contractor before the delivery truck arrives avoids finding out the hard way on-site.
Coverage under the slab is the whole point of back-buttering
Back-buttering means applying adhesive to the back of the slab itself, as well as to the substrate, and combing both in the same direction before the slab goes down. For a small tile, skipping this step is a shortcut that usually works. For a large-format slab, however, skipping it leaves air pockets under a surface that has almost no give, and an air pocket under a rigid, unsupported slab is exactly where a crack starts once furniture, foot traffic, or a dropped object puts pressure on that spot.
Large-format work also needs adhesive built for the job, a deformable, polymer-modified cementitious mortar, commonly labelled S1 or S2 under the relevant adhesive standard, rather than a standard-duty mix. Coverage should reach close to full contact under the slab, not the 60 to 70% that a smaller tile can sometimes get away with. The only real way to confirm this on-site is to lift a slab early in the run and check the adhesive transfer on the back before committing to the rest of the floor.
Lippage gets less forgiving as the tile gets bigger
Lippage is the height difference between the edges of two adjacent tiles, and it's one of the clearest tells that a large-format installation was rushed. A small tile can absorb a couple of millimetres of substrate unevenness without anyone noticing. A 160×320cm slab has nowhere to hide that same unevenness; it's rigid enough to sit exactly as flat, or as uneven, as the surface underneath it.
Substrate flatness has to be checked before adhesive goes down, not assumed. The most widely used benchmark for large-format tile comes from the ANSI A108.01 standard, referenced in the Tile Council of North America's installation handbook: no more than 1/8 inch of variance over 10 feet, tightening to 1/16 inch over 24 inches at the high points. Converted to metric, that works out to roughly 3mm over 3 metres, tightening to around 1.5mm over 600mm; anything beyond that needs correction before large-format tile goes anywhere near it. Once the slabs are down, tile levelling clips or wedges hold adjacent edges flush while the adhesive cures, which is the difference between a floor that looks flat under raking light and one that doesn't.
A mockup costs an afternoon. A redo costs a floor.
A site mockup, laying out a small run of the actual slabs before committing to the full area, earns its place on every large-format job, even when the schedule is tight. It's the cheapest way to catch three things before they become expensive: substrate flatness that looked fine on paper and isn't, shade or batch variation between slabs that only shows once they're side by side, and a joint width that shows up differently at this scale than it did on the drawing.
None of these problems is difficult to fix before installation starts. All three are expensive once forty square metres of slab are already bonded to the floor.
Where large-format stops making sense
Not every space needs a slab this size. A powder room, a small utility area, or a room broken up by columns and fixtures often works better in 60×120cm or 60×60cm formats that are easier to cut around obstacles, need less specialised handling, and forgive a slightly less-than-perfect substrate. Large-format earns its keep in open floor plans, feature walls, and spaces where the visual continuity of fewer joints is the whole point of the specification. Matching the format to the room, rather than defaulting to the largest size on the price list, keeps both the budget and the installation timeline realistic.
Grifine's 120×280cm and 160×320cm ranges are built for that continuity, long, uninterrupted runs with as few joints as the room allows. Getting the result the format promises depends on the installation matching the material, which is really what all of this comes down to.
FAQ
Do I need a specialist installation crew for large-format slabs?
Not necessarily a separate specialist company, but the crew does need the right equipment, vacuum lifters, A-frame transport, and levelling systems, and experience with slabs this size, particularly for Grifine's 120×280cm and 160×320cm ranges. A team used to standard-format tile can usually adapt, but they should do it on a mockup first, not on the actual floor.
What's the difference between back-buttering and standard adhesive application?
Standard application spreads adhesive on the substrate only. Back-buttering adds a second, combed layer on the back of the slab itself, so the two layers merge into full coverage when the slab is set. It takes longer per slab, and it's the single most common step skipped under schedule pressure.
How much lippage is acceptable on a large-format floor?
Industry guidance generally allows around 1mm, sometimes slightly more with wider grout joints, but the real answer depends on the specific standard the project is following. It's worth agreeing this number with the contractor in writing before installation starts, not after someone notices a shadow line under raking light.
Can large-format slabs go over an existing floor?
Sometimes, but the existing surface needs the same flatness check as any other substrate, and it needs to be structurally sound and free of movement. This isn't a large-format-specific question so much as a reminder that skipping substrate prep causes the same problems regardless of tile size; it just shows up faster and more visibly at 160×320cm.
Is 120×280cm or 160×320cm the right call for a residential project?
It depends on the room more than the budget. Large open floors and feature walls make the most of the format. Broken-up rooms with a lot of fixtures often get better value and an easier installation from 60×120cm or 60×60cm.
(The handling, adhesive, and lippage benchmarks in this piece reflect general industry practice for large-format tile installation. Actual requirements can vary by project, substrate, and site condition; always confirm specifics with your installation contractor before work begins.)*
