Your Guide to Screed and Underfloor Heating

Underfloor heating (UFH) is an increasingly popular method for heating homes and commercial spaces. That’s because it offers an even and effective warmth throughout a room, and has a stylish, minimalist aesthetic without using up any wall space, as there’s no need for radiators.

Underfloor heating can be combined with just about any flooring type, including carpet, tiles and laminate, with a layer of screed below to ensure a level surface. However, your choice of screed is important when it’s to be combined with UFH, and in this article, we’re going to explore the different types of screed and how they impact the efficiency of your underfloor heating.

What is an underfloor heating screed?

Screed is a cement-based material usually laid on top of concrete to create a smooth and level surface. Underfloor heating, on the other hand, uses either hot water or electricity to provide heating to a room from below.

How these systems work together can have a significant impact on how well your home or premises is heated.

Screed mixes for underfloor heating

Traditional sand-based screed: Dry screeds are made using a combination of cement, water and sand and are a cost-effective solution, particularly when used in small rooms in residential properties, such as bathrooms. Once installed, they provide superb, long-term heat retention. However, they need to be laid thickly and can take several weeks to dry. There’s also the risk that when laid on delicate heating systems, damage can be caused when compacting cement and sand screed to remove air bubbles. 

Self-levelling liquid screed: The great advantage with a self-levelling screed is that it flows smoothly around the elements of your UFH system under its own steam, reducing the potential for damage in the process. That ensures a particularly smooth surface, but does require laitance to be removed afterwards to ensure the best results. Self-levelling screeds are commonly used in large commercial spaces, as they are quicker to lay than traditional cement screed.

Fast-drying screed: The main benefit of fast-drying screed is all in the name, and this will always be a good choice when you have a tight schedule. In fact, some fast-drying screeds can be walked on in as little as 24 hours after pouring, while the drying time can often be improved even more by turning on the underfloor heating.

Key features to look out for in underfloor heating screeds

• Thermal conductivity – Perhaps the most important thing you want from your underfloor heating is that it warms your room effectively, and the best for this will usually be liquid screeds, particularly in large spaces.
• Strength – Once installed, you’ll want your underfloor heating screed to be able to last for many years. You’ll usually find that traditional and fast-drying screeds offer the best durability.
• Ease of pour – Self-levelling and liquid screeds will be quicker and easier to pour, and require less labour, meaning that, although they are generally more expensive than traditional screed, some of that extra cost can be made back with reduced labour costs. 
• Drying time – If time is a significant factor, then a fast-drying screed can cut the drying time by a significant amount.
• Value – If you’re after a cost-effective solution that doesn’t compromise on strength and thermal conductivity, then a traditional screed will always be a good choice.

Here at Stewart Brothers Concrete, we supply screed in a wide variety of different mixes to meet the individual needs of your project, with our expert team always available to provide advice on the right solution.

Get in touch today for more information and to get your competitive quote.

For more information on Your Guide to Screed and Underfloor Heating talk to Stewart Brothers Concrete