The more you know about the conditions at which your floor is going to operate, the easier you can prolong its life. As floors are affected from two directions, above and underneath, it’s important to provide good conditions on both sides. While you can always look after the surface as long as you follow the right maintenance tips, the underside of the floor is not something you can easily work with once the floor has been installed. That’s why having the best possible laminate floor underlay is essential.
1. Before you go on to look for an underlay for your laminate floor, take your time and observe your sub-floor. Is it concrete slab or timber boards? Find out as much as possible about its structure, any damage that it has or may potentially develop, the moisture level beneath, at and above it.
2. In order for the underlayment to work properly, your sub-floor has to be as level and as clean as possible. If it’s a concrete one, fill in any gaps that exist using a compound mixture and scrape off any adherent carpet and other left-overs. If it’s a timber sub-floor, nail properly all boards and use plywood sheets if necessary to level out the surface.
3. If the level of moisture in your area is high or has the potential to reach high levels over an year, and you have a solid sub-floor (concrete slab, stone, brick), use a damp proof filler compound to fill in any gaps. Make sure to give it enough time to dry out before moving onward with the job.
4. Depending on your budget and personal demands you can choose foam, cork, plywood or a combination of these. Additional layers of sound absorbing materials are also available, either separately or built-in, but might cost you more. Generally you would want to have the latter on upper floors where sound is more of a problem. Ground floors on the other hand are more susceptible to moisture and the aim there is to have good moisture insulation.
5. Before deciding on the type of underlay, check if your laminate flooring doesn’t come with an underlay of its own. Very often Do-It-Yourself laminate floors are pre-finished and don’t require additional custom underlay installation. That said, custom separate layers for shock and sound absorption are always an option. It helps reduce the “hard” feeling and reduce the hollow sound noise that are so typical when walking over laminate.
6. Damp proof membrane (DPM) is necessary when you have a solid sub-floor, especially if it’s a new one. Timber sub-floors on the other hand need to breathe to avoid the build-up of mold in the near future and DPM should be avoided. Installing foam to level out irregularities and create a cushion is often enough in these cases.
The important thing is to know your level of moisture before making any of these decisions.