Screed is one of the beneficial materials which help achieve flat surfaces with even load distribution and covering underfloor heating systems for efficient heat transfer. It is a thin layer of material which usually consist of:
In this guide, you can explore two significant types of screeds, i.e., dry and flowing screed, along with their advantages and disadvantages. In this way, you can get help to make an informed decision regarding the selection of a particular type of screed before starting your project.
Based on the materials and application methods, there are two broad categories of screed, which include:
- Dry/Traditional Floor Screed
- Flowing/ Liquid/Wet Floor Screed
Dry screed is also known as traditional screed as it has wide-ranging applications in various industries and commercial properties. It comprises aggregates and cement in an estimated ratio of 4:1. Moreover, mesh or fibres can be added to the mixture to enhance floor strength and durability by reducing the risk of cracks and shrinkage.
It helps to create a thick layer that gets clumped together upon squeezing, requiring manual application. A float and trowel are used for sequentially applying dry screed.
Pros of Dry Screed
- It incurs less cost, considering the price of material and labour costs.
- It is suitable for application in wet rooms.
- It helps to create a hard-wearing and durable surface suitable for heavy-load applications.
- It becomes non-absorbent after curing, providing resistance against dampness and making it suitable for installation in basement.
- It can be cleaned easily using a stiff brush and warm, soapy water.
- Its aesthetic look can be improved by polishing.
Cons of Dry Screed
- It is challenging to repair larger cracks, fissures, or potholes, requiring the entire floor’s replacement which needs more cost.
- It does not create a flexible surface and is more prone towards cracking in case of general subsidence or land movement.
Flowing screed is also referred to as liquid screed which helps to make the surfaces levelled, providing a smooth floor finish. Calcium sulphate is added in the screed which acts as a binding agent. It reacts with water to create gypsum, making it an ideal mixture for levelling the floor surfaces with added durability.
It involves fewer and smaller in size aggregates; that’s why it has a flowing liquid-like consistency, allowing easy pouring on surfaces. It can ideally be used in domestic and commercial building spaces. A pump is used to pour a self-compacting flowing screed over the subfloor, filling up all the available space by arranging itself.
- It can be applied quickly due to easy handling and pouring in one go, leading to faster completion of the project.
- It enhances the thermal conductivity, leading to efficient heating.
- It involves less labour for spreading and distributing the material on the floor.
- It makes the floor surface durable and robust, making it ideal for use in high-traffic areas.
- It dries quickly, almost within 24 hours after its application.
- It provides space for installing thicker insulation.
- It eliminates the risk of the appearance of cracks or shrinkage of surfaces once its thin layer gets dried.
- It is cost-effective as it involves using less material to create a thin layer, reducing the overall costs.
- It offers low environmental impacts, making it a sustainable and eco-friendly choice.
- It is a remedy for precast concrete beams and block floors that may cause problems when installing the final floor surface.
- It requires to prepare of the initial pouring surface effectively.
- It requires you to invest in insulating the floor by covering it with polythene.
- It needs the sanding of the final product to avoid potentially impairing of floor laid above it.
Dry Screed & Flowing Screed – Which One to Choose?
You can choose to install dry screed if you have a limited budget, as it is a cost-effective solution, but you should be aware of long-term costs associated with poor heat retention and more energy bills.
On the other hand, flowing screed provides value for time and money as it offers better insulation and thermal conductivity, ultimately leading to lower energy bills.
Screed helps to fulfil the unique requirements of your project and significantly impacts its outcome. Therefore, it is crucial to critically analyse all the pros and cons of liquid screed types before choosing one for your project.