Handing a screeded area over to the flooring contractor is an important moment. Get it right and the floor finish goes down smoothly. Miss something and the problems can show up weeks later. The Screed Scientist has put together this checklist to help site teams cover the essentials.
Use it alongside the screed, floor covering and adhesive manufacturers’ guidance, BS 8204 and BS 8203, and your project’s own requirements.
1. Screed details
- ☐ Screed type and product recorded, including the manufacturer.
- ☐ Laying dates recorded for each area.
- ☐ Thickness recorded, including any thicker areas.
- ☐ Build-up recorded: membranes, insulation and underfloor heating.
- ☐ Areas marked on a drawing.
2. Drying
- ☐ Building weathertight during drying.
- ☐ Conditions recorded (temperature and humidity).
- ☐ Drying time planned using the standard guide as a starting point: 1mm per day for the first 40mm, then 0.5mm per day beyond 40mm, in laboratory conditions. Remember site drying is usually slower.
- ☐ Any force drying recorded. Flowing screed can be force dried after 7 days, following the manufacturer’s guidance.
- ☐ Underfloor heating commissioning carried out and recorded, if applicable, following the heating and screed manufacturers’ procedures.
3. Moisture testing
- ☐ Acceptable readings confirmed with the screed, floor covering and adhesive manufacturers.
- ☐ Test method agreed: hygrometer (RH) test or calcium carbide (CM) test. The CM test is a preferred method of the Screed Scientist and many proprietary screed manufacturers.
- ☐ Hygrometer tests: yellow hood box sealed to the floor and left to settle, normally 72 hours, checking the manufacturer’s guidelines.
- ☐ CM tests: sample taken through the depth of the screed and tested in the silver flask with the pressure gauge.
- ☐ Tests taken in several locations, including slower-drying areas such as corners, thicker sections and rooms with poor airflow.
- ☐ Results, locations, dates, conditions and tester’s name recorded, with photographs.
4. Surface condition
- ☐ Surface checked for level and flatness against the specification.
- ☐ Any surface laitance or contamination noted for preparation, following the manufacturer’s guidance.
- ☐ Any cracks or other defects recorded and discussed.
- ☐ Surface clean and free of debris.
5. If the screed isn’t ready
- ☐ Further drying time agreed and recorded.
- ☐ Options discussed with the manufacturers and flooring contractor, such as a surface DPM. A surface DPM is laid on top of the screed to suppress moisture and control moisture evaporation so it isn’t harmful to sensitive floor finishes.
- ☐ Retest dates planned.
6. Sign-off and records
- ☐ Handover areas confirmed on a drawing.
- ☐ Test results and notes shared with the flooring contractor before they start.
- ☐ Each party has signed off for their own part of the work, with names and dates.
- ☐ Everything stored in the handover file.
Why a checklist helps
Handover often happens under time pressure, with several trades waiting to start. It’s easy for a test to be missed, or for results to sit in one person’s notebook. Working through the same list on every floor, and agreeing who owns each step at the start of the project, keeps everyone aligned. Print it, add it to the handover file, and tick items off as they’re done rather than all at once at the end.
A checklist turns good intentions into a routine. It makes sure testing actually happens, that the right people see the results, and that the information is in one place if anyone needs it later. For more on records, see Avoiding Disputes: Records and Sign-off.
Need help?
CSC Screeding was Established in 1987 and lays up to 1,000m² a day of flowing screed on suitable projects. The Screed Scientist is here to share that know-how so every floor gets off to the right start.
Back to the start of the series: Why Damp Screed Ruins New Flooring
