Why subfloor preparation matters

The work you do not see

When you look at a finished floor, you notice its colour, layout and texture. Preparation is less visible, but it is part of the installation rather than an optional cosmetic extra. The existing base needs to be assessed against the requirements of the selected flooring system.

The Six Flooring & Co discusses the substrate and known concerns before confirming the scope. Photographs help begin that conversation, although some conditions can only be assessed fully once the old covering is removed.

Flat and level are different questions

A floor can slope while still being relatively flat. Conversely, a surface can be broadly level but have local dips or high spots. Ask what the selected product requires and how the existing substrate will be checked; “it looks level” is not a complete installation assessment.

The allowable tolerances and suitable preparation method depend on the system. This guide deliberately does not prescribe one universal measurement or levelling product for every floor.

Tell us what you have noticed

Mention movement, squeaks, cracks, previous repairs, damp areas and changes in height between rooms. Share any information about what lies beneath the current covering. These details help identify questions for the site assessment, even when they do not establish the cause on their own.

Do not assume a thicker plank or softer underlay will compensate for an unsuitable substrate. The complete assembly needs to follow the chosen product’s requirements.

Make preparation visible in the quote

Ask which tasks are known and included, which conditions remain unconfirmed and how additional work would be approved. Depending on the site and system, the conversation may include removal, cleaning, local repairs, surface preparation or a suitable levelling approach.

These tasks are not all necessary on every project. The important point is that the proposed work follows an assessment rather than a fixed package applied regardless of the room.

Think about the final floor height

Preparation materials and the new flooring assembly can affect thresholds, doors, stairs and adjoining surfaces. Discuss those junctions before installation. A technically suitable base still needs to work with the room’s practical clearances and intended finish.

• Ask which manufacturer instructions apply to your chosen floor.
• Request an explanation of the proposed preparation.
• Confirm whether removal and disposal are included.
• Agree how newly uncovered conditions will be documented.
• Review transitions and finishing details alongside the substrate work.

A better starting conversation

Bring The Six Flooring & Co photographs of the current surface and any problem areas, plus approximate dimensions and your preferred materials. We can then discuss the information needed to develop the installation scope. Understanding the base early helps you compare complete projects rather than isolated material prices.