How Fast? Floor Screed Drying Time
I’m Andy Parkin, Managing Director of the Multi-Award Winning Speed Screed. I am going to look at floor screed drying time and when you can lay the final floor covering on your screed.
How long does floor screed take to dry? What is the average floor screed drying time?
Understandably, you are unable to lay a final floor covering onto your screed until you know that the screed is dry enough. Floor screed drying time always refers to the amount of time it takes from the initial installation of the screed until the final flooring can be installed. This is not the same as the walkable time which is often a lot shorter. This is an important distinction.
What can impact floor screed drying time?
The two main factors that affect the amount of time the screed takes to dry out enough to take a final floor covering are temperature and humidity. When a manufacturer lists a drying time on a product it is usually based on a temperature of 20oC and relative humidity of 60%. Any variation to this impacts the drying time.
How can I tell that the screed is dry?
Industry standard is that to accept a floor covering a screed should measure 75% relative humidity, but this is also subject to the manufacturer’s instructions. The only way to be sure is to test the screed and this can be done in a variety of ways. Again, always check with the manufacturer which one they recommend. Never be tempted to skip a test – manufacturers can only provide guidance, they are not aware of the specifics of your installation.
Floor Screed Drying Time – General Guidelines
For calcium sulphate screed expect to allow 1 day per mm of screed for floor screeds of 1-40mm thickness, and 2 days for each addition 1mm over 40mm (75mm = 110 days).
For the fast-drying screeds, expect 14-21 days as standard (75mm = 21 days).
For sand and cement expect 1mm a day drying time for floors of 1-50mm thickness. If the screed is more than 50mm allow 1 day per 1mm up to 50mm and then extra time for every millimetre over 50mm. Using this formula you would expect a drying time of 75-100 days for a 75mm screed layer.
Other common types of screed have different drying times so always check the manufacturer’s guidelines and be sure to do a proper test before moving on to the next stage.
You may have realised that there is no ‘one size fits all’ when it comes to floor screed drying time. One of the best ways to help you plan your project is to take account of what the likely weather conditions and other environmental factors are going to be when you expect to start the screeding process. This will give a good indication of any delays in drying time and help keep the project on track.
If you have any more questions about floor screed drying times just get in touch, we are always happy to help and give advice on the best floor screed options for your construction.