We recommend reading the Energy Savings Trust web page on insulating your floor.
https://energysavingtrust.org.uk/advice/floor-insulation/
Savings can be around £40 per year and you gain a more comfortable room. Insulating your ground floor is a great way to keep your property warm. Generally speaking, you only need to insulate the ground floor. If you’re on an upper floor, you don’t usually need to insulate your floor space. However, you should consider insulating any floors that are above unheated spaces such as garages, as you could be losing a lot of heat through those.
The Ezy Fit underfloor insulation system is designed for suspended timber floors. That is the type with wooden flooring with a void under it. The void can be small or could be as large as a cellar but one way of checking is by making sure there are air vents on the outside walls of the floor you wish to insulate.
We always recommend gaining professional advice before continuing with any insulation work to your home to ensure compliance with building regulations.