Flooring · 8 min read · Intermediate

Laminate Flooring Basics: Planning, Underlay & Expansion Gaps

Plan a floating laminate floor properly, including subfloor condition, underlay, expansion gaps, staggered joints and manufacturer-specific limits.

Key points & steps

Read the flooring manufacturer’s installation instructions before planning the room. Expansion gaps, maximum uninterrupted floor dimensions, underlay and moisture requirements can differ between products.
Check that the subfloor is clean, dry, stable and sufficiently flat for the flooring system. Correct local high spots, loose boards or significant hollows before laying the floor.
Confirm whether a damp-proof membrane or combined underlay is required for the particular subfloor and product, especially over mineral or concrete-based floors.
Plan the board direction and first/last row widths before starting so that you avoid a very narrow final strip or awkward layout around doorways.
Leave the expansion clearance specified by the manufacturer around walls, pipes, frames and other fixed objects. Some common laminate systems specify around 8–10mm, but the product instructions take priority.
Stagger short-end joints by at least the manufacturer’s minimum distance and avoid repeating a weak, regular stair-step pattern unless the product instructions permit it.
Use suitable threshold or expansion profiles where required between rooms, across large/complex areas or where the manufacturer specifies a break in the floating floor.
Do not trap a floating floor under fixed cabinetry or other installations unless the flooring manufacturer explicitly permits that arrangement.

A floating floor must be able to expand and contract; skirting or beading hides the perimeter gap but should not pin the floor down.
Check underfloor-heating limits for both the laminate and underlay before installation.
Door frames often need careful undercutting so the floor can pass beneath while maintaining its required movement gap.