Now more than ever, the construction industry is under immense pressure. Apart from the obvious financial issues, these companies have to factor in: time restraints, environmental considerations, changes in technology, customer satisfaction, keeping ahead of competitors, as well as juggling a workforce which involves a multitude of professional trades.
Delays can be quite expensive, annoying and can have a catastrophic impact on the project. When it comes to using screed for flooring, waiting for it to dry can bring the project to a grinding halt.
Due to this, the further construction process ceases, whilst the workforce is not able to access that particular area. However, to get the best end results it is vital to let the screed dry properly before laying the floor coverings.
What is Liquid Screed?
Basically, liquid screed also known as “flowing screed” is a levelling compound that is added to the surface in order to craft a levelled floor and to bring it to a specific construction height.
They are normally prepared from pre-blended mortar, which is either mixed with cement or anhydrous based binders. Depending upon the conditions different types of suitable screeds can be chosen.
Factors to Consider when Drying Liquid Screed
When you are drying the liquid screed you need to consider four factors, which are as follows:
- Room Temperature: You have to ensure that the temperature of the room where the screed has been laid is increased. This will help the screed in drying through increased evaporation.
- Relative Humidity (RH): For a screed to dry properly it is essential to provide it with good ventilation to make sure that a relatively low RH is attained.
- Screed Temperature: If you are installing an underfloor heating system then it can be commissioned (including the heating and cooling procedure) in 7 days. This raises the vapour pressure, thereby greatly improving the screed’s drying rate.
- Moisture Ingress: When you are using liquid screed to acquire a levelled floor, you need to ensure that it is protected from moisture ingress. This in turn prevents rehydration which can delay the entire drying process.
Liquid Screed Setting and Drying Time
Once the screed is laid on the surface it is important to ensure that the right conditions are provided right from the beginning, in order to create an optimal environment for it to dry.
It is quite obvious that conditions may vary which will in turn affect the screed’s drying time. Thus, the ideal atmosphere has to be well-ventilated and warm.
Gyvlon is a flowing screed which is often used with underfloor heating (UFH). Depending upon the conditions, this screed’s thickness is ~40mm which takes an average rate of 1 mm per day to dry.
Gyvlon screed can be forced dried 7 days after its insulation. When this screed is used, the lower flow temperature of 20-25°C for a minimum of 3 days can be raised with an increment of 5°C to a maximum water level of 55°C. This temperature should be returned to ambient temperature using a reverse process along with an increment of 5°C.
Once the liquid screed has been dried, an approved test method is used in order to assess residual moisture levels before laying the flooring. Most of the floor screed acquires its maximum strength on the 28th day after being laid.