Onsite Supervision Checklist for Screeding Projects

Onsite Supervision Checklist for Screeding Projects

Effective onsite supervision is critical to achieving a quality screed installation. This comprehensive checklist covers the key inspection points from pre-pour verification through to post-installation protection, giving site managers and supervisors a practical framework to follow.

Before Screeding Begins

1. Verify the Screed Specification

Before any materials arrive on site, confirm the screed specification matches the project requirements:

  • Screed type (bonded, unbonded, or floating) matches the structural engineer's design
  • Minimum thickness is achievable given the substrate condition and any services or insulation
  • Strength class and surface regularity requirements are clearly documented
  • Drying time has been factored into the project programme — particularly important if fast-track floor finishes are planned
  • Underfloor heating compatibility has been confirmed if UFH is present

2. Inspect the Structural Base

Walk the floor area and check:

  • The substrate is clean, free from debris, standing water, and contaminants
  • Any DPM or separating membranes are correctly lapped, sealed, and turned up at perimeters
  • Insulation boards are tightly butted with joints taped and staggered
  • Perimeter strips are in place around all walls, columns, door frames, and penetrations
  • Datum points and level marks are clearly visible and correspond to the screed thickness drawing

3. Confirm Base Preparation

For bonded screeds, verify that the substrate has been mechanically prepared (shot blasted, scabbled, or ground) and that the bonding agent or slurry application is planned for the correct timing. For unbonded and floating constructions, check that the separating layer is intact with no tears or gaps.

During Screeding

4. Check Mix Proportions

Whether site-mixed or ready-mixed, verify:

  • Sand and cement proportions match the specification (typically 1:3 to 1:4.5 cement:sand by weight for standard mixes)
  • Water content is controlled — the screed should pass the ball-in-hand test without releasing free water
  • Any admixtures or fibres are being added at the correct dosage rate
  • Mixing is thorough and consistent — check several batches, not just the first one

5. Monitor Batching and Mixing

For site-mixed screeds, observe the batching process:

  • Are gauge boxes or weigh batchers being used, or is batching by shovel (unreliable)?
  • Is the mixing equipment producing a consistent, uniform mix?
  • Are materials being measured consistently from batch to batch?

6. Observe Laying and Compaction

Watch the laying team at work and check:

  • Screed is being placed and compacted in a systematic pattern, working towards an exit point
  • Compaction is thorough — the screed should be tamped firmly to eliminate voids, especially around pipes, ducts, and at perimeters
  • Bay sizes are appropriate and day joints are properly formed
  • The surface is being finished to the required regularity standard using a straightedge

After Screeding

7. Check the Finish

Once laying is complete in each area:

  • Use a 2-metre straightedge to check surface regularity against the specified SR classification
  • Verify levels against datum points — is the screed at the correct finished floor level?
  • Look for surface defects: trowel marks, laitance, areas of poor compaction, or visible cracking

8. Verify Curing Arrangements

Proper curing is essential for strength development:

  • Is the screed being covered with polyethylene sheeting within the specified timeframe?
  • Are doors and windows closed to prevent draughts?
  • In cold weather, is temporary heating in place and set to maintain temperature above 5°C?
  • Has the curing period been communicated to all site trades?

9. Arrange Protection

Before other trades access the screeded areas:

  • Adequate hardboard or plywood protection is in place over traffic routes
  • Edge protection strips are installed at vulnerable locations
  • Signage is in place indicating that the area is a curing zone with restricted access
  • A minimum foot-traffic restriction period has been communicated (typically 24-48 hours minimum)

10. Plan for Testing

Schedule any required testing in advance:

  • Surface regularity testing should be carried out once the screed is hard enough to walk on without damage
  • Strength testing (BRE screed tester) at the specified age — typically 28 days for standard screeds
  • Moisture testing before any floor finishes are applied — use calibrated hygrometer or calcium carbide methods

Download this checklist and adapt it for your specific project. For product-specific installation guidance, contact our technical team.

Call us on 0118 370 2060 for expert advice on your project. Free delivery on orders over £600 ex-VAT.