If you are in the course of building a new property from scratch, then you would be wise to include underfloor heating rather than using a radiator system. There are many advantages to underfloor heating, not the least of which is that you save as much as 10% of the space in the room that would be taken up by a radiator system and the pipework.
In fact, underfloor heating is nothing new. It has now been traced back around 7,000 years when trenches were cut into the floors and covered with stones which were then heated by a fire in an appropriate place.
Obviously, things have changed somewhat over the intervening period, and we now have underfloor heating systems that can be either water-based or electric. An electric underfloor heating system uses a heating cable running under the floor, or a heating mat which is a mat that contains a fine heating cable running through it. Water-based systems use heated water which is pumped through pipework laid under the floor.
Compared with water-based systems, an electric underfloor heating system can be quite expensive to run because electricity tariffs are not cheap. But whichever type of underfloor heating system you install, one thing is for sure, and that is that it needs to be covered with a screed. For years now, screeds have been made of sand and cement and have then been laid by hand by a labourer using a trowel, and endeavouring to achieve as level a surface as possible on which to lay the final flooring, whatever that may be.
However, today we now have the introduction of liquid flowing screeds which have gained rapidly in popularity over the last 20 years or so because of the benefits that they have over sand and cement screeds. They are far quicker to lay than sand and cement because, being liquid, they are delivered to the site ready mixed and then connected to a pump and hose and simply pumped into position. One very big advantage is that they totally envelop the heating pipes on a water-based heating system, leaving no voids or gaps, which is almost impossible to achieve when laying a sand and cement screed by hand. This means that the heat that goes into the room is spread completely evenly across the floor, so there are no cold spots.
There is another big advantage of liquid screeds, and that is that they can be force dried quickly and safely. This is because liquid screeds do not curl, and they do not need any reinforcement. Shrinkage is very low too, and large bays can be laid without the chance of them cracking.
The drying times of screeds can be a big issue for contractors. Overruns on contracts can result in penalties which can run into hundreds of thousands of pounds in some instances, and this can be a major hazard for project managers trying to plan work schedules.
The drying times of liquid screeds are calculated as 1mm depth per day for the first 40mm and 1/2mm per day for anything deeper. So, theoretically, a 50mm deep screed would take 60 days to dry. However, this is calculated by screed manufacturers working on the basis that the temperature is 20°C and the relative humidity is 60% for the whole of the drying period. In practice, this is pretty unlikely to occur in the UK, and so there are almost always overruns, and a 50mm screed could easily take 90 days to dry. As a liquid screed company in Newbury, at UK Screeds we can confirm this.
However, if you use force drying, this can reduce the overall drying time of the screed before the final flooring can be added down to as little as four weeks. The key to successful force drying is taking control of the environment, including the temperature and humidity, and appropriate moisture testing while using specialist force drying equipment.
When you are working on a construction site, time is money, and being able to reduce the overall drying time by two months means that there is a considerable cost-saving for developers and contractors, and it also means that there is an element of certainty, which is welcome on any project.