**To get the same finished height throughout, the installer will need to correct the height difference before laying the laminate.** Using the same laminate in every room will leave the existing difference in place.

There are three main options:

- **Raise the lower areas:** Add appropriately sized plywood to the living room and hallway, securely fastened to the existing subfloor. For a difference caused by extra plywood layers, this is often a practical solution.
- **Lower the dining area:** Remove the extra plywood layers if inspection confirms they are removable underlayment and aren’t needed for structural support.
- **Keep the different heights:** Install separate sections of laminate and join them with a reducer transition strip rated for the measured difference. Matching profiles are available for this purpose. [Quick-Step transition profiles](https://www.quick-step.co.uk/en-gb/laminate/accessories/laminate-profiles)

After addressing the overall height difference, the installer may need to smooth smaller irregularities with a compound approved for plywood. Laminate needs a firm, flat supporting surface; the exact flatness requirement comes from your flooring’s installation instructions. [Quick-Step installation guidance](https://www.quick-step.co.uk/en-gb/frequently-asked-questions/laminate/general/can-quick-step-laminate-be-installed-on-top-of-an-existing-floor-covering)

**Don’t use stacked foam underlay to make up the missing plywood height.** Excess cushioning can let the boards flex and strain their locking joints.

Have the installer inspect and measure the exposed floors before installation, explain the proposed solution, and include preparation costs in the quote. If they raise the lower areas, they should also check door clearances and kitchen appliance clearance—particularly whether the dishwasher can still be removed.