Aftercare

After we leave, you’ll need to know how to take care of your new screed and prepare it for your chosen floor covering.

Please see our easy to follow, step-by-step guide below which covers everything including drying, laitence removal and priming.

1. Curing…

Following installation, the environment must remain sealed for 2 days.

During this period, the screed should be protected from excessive sunlight, frost and drafts.

Where windows and doors are not installed, a temporary provision must be made to seal windows and doors.

2. Trafficking

Liquid Screed can usually accept light foot traffic after 24-48 hours.

3. Drying…

Under ideal drying conditions (a well-ventilated room) Liquid Screed dries at a rate of 1mm/day up to a thickness of 40mm, and then at a rate of 0.5mm/day for thickness above this.

Example – 50mm Liquid Screed drying time:

(40 x 1mm per day) + (10mm x 0.5mm per day) = 60 days (2 months) (Guidance only)

NB: Drying of screeds can be greatly influenced by individual site conditions

Drying times can be reduced by provision of good ventilation by opening windows and doors, the use of dehumidifiers and commissioning of underfloor heating systems to manufacturers guidelines and recommendations.

Dehumidifiers can be used as early as 72 hours after the placing of Liquid Screed to assist with drying. It is important that a closed system is employed to ensure that any moisture extracted from the environment during operation is removed.

Force drying of Liquid Screed can begin as early as seven days following installation of the screed by the following method:

Commissioning (heating and cooling procedure) of underfloor heating systems. Set flow temperature to 20-25oC, maintain for a minimum of 24 hours and then gradually increase the temperature in 5oC increments to maximum operating temperature. This should be maintained for a further seven days (water temperature should not exceed 55oC for screeds), prior to returning to ambient temperature again in 5oC increments. Then the system should be turned off for 48 hours prior to moisture testing of the screed.

4. Sanding

Liquid Screed will require sanding to remove surface laitance. Sanding at 7-10 days will also improve drying performance. Sanding will also provide a surface key prior to the application of subsequent floor coverings. The dust residue will need to be vacuumed up.

5. Moisture Testing

As with all screeds, in good conditions Liquid Screed has a natural drying time of 1mm per day up to 40mm and 0.5mm after that, drying times can be greatly affected by site conditions, so it is advised to keep the environment as dry as possible.  Commissioning of the UFH and/or using dehumidifiers can greatly improve the figures above.  Prior to the application of coverings, the screed moisture must be tested using a hygrometer and be below 75% RH (0.5% moisture).  NB: It may be possible to use gypsum based products at 85% RH – manufacturers must be consulted.

6. Underfloor Heating Commissioning

Where underfloor heating is used this must be commissioned and run prior to the application of floor coverings regardless of how dry the screed may be, this is in line with CFA, TTA, vinyl and tile manufactures’ guidelines.

This process forces additional moisture from the screed and conditions it to thermal movement prior to coverings.

Typically, the commissioning cycle is 21 days and can be started as early as seven days.

7. Priming

Your liquid screed will require priming prior to application of adhesives.  Please consult adhesive manufacturer for advice.