Learn more about Underlays
Why use an Underlay?
Having a good underlay is critical to ensuring the performance and longevity of your floating floor (apart from hybrid that comes with pre-attached underlay).- Quieter footsteps - separates the floorboard from the hard substrate and dampens any foot-impact on the floor.
- Impact noise insulation - helps reduce sound travelling below (downstairs) and bouncing upwards.
- Provides insulation - helps keep the floor feeling more comfortable and insulated from any underfloor cold or dampness (if there is a moisture barrier).
- Brings up floor height - in certain circumstances, underlays are used to bring up floor thicknesses to meet other floors, doorways or bring different rooms to the same level.
Floors that Require Underlay
- Timber - engineered timber is floated i.e. clicked or glued to each other, rather than the subfloor. This is with the exception of direct stick to underlay i.e. when the floor is glued to rubber underlay and then glued to the subfloor.
- Laminate - as a click-lock floating floor, it should be floated over a suitable underlay.
- Bamboo - is generally installed as a floating floor and should also be floated over underlay.
In less common circumstances, hybrid floors can also be installed over an underlay, but typically they would only be acceptable over high-density and firm rubber underlays, as most cheaper and softer foam underlays compress too much under weight and will cause the click-lock systems to break.
Flooring Works warrants our 3mm High-Density Rubber underneath all our hybrid flooring and 5mm high-density rubber under our 9mm and 10mm hybrid floors in a residential context when installed in accordance with our installation instructions.
Acoustic Requirements for Underlay
If you are in a strata building, your committee may have an AAAC star requirement e.g. 4, 5 or 6 star. The only method of guaranteeing a result is doing an on-site test, however many strata committees accept previous testing as an indication of future performance - keep in mind the strata committee or you are taking responsibility and we can never guarantee any result as every building is different. All acoustic testing for underlays stocked by Flooring Works is available upon request: contact@flooringworks.com.auHow to Choose Underlay
It comes down to your requirements, in short:- Foam Underlays - are budget-friendly options that come with a moisture barrier. If you’re looking for a basic option that doesn’t offer significant acoustic performance that will meet requirements for most floors, then these are your options:
- 2mm Silver
- 3mm Gold
- 2mm Acoustic IXPE - this is a high density closed cell foam underlay of approximately 70kg/m3 density, so it does offer acoustic performance and is suitable for most residential applications.
- Rubber Underlays - are high-performance underlays that are strong and bounce back against pressure and weight. They are very firm and heavy with rolls typically with density between 650 - 850kg/m3, over 20 - 30 times the strength of cheaper foam underlays. Rubber underlays have strong acoustic performance and will last under weight loads for decades i.e. they will not flatten out as easily as foam. Under higher weight loads or commercial spaces, rubber is typically recommended as many foam underlay may “bottom out”.
- 3mm Rubber
- 5mm Rubber-Foam & 5mm Rubber
- 10mm Rubber
How to Install Underlay
Most underlays are very easy to install:- Rolls - can be rolled out across the entire subfloor and joints can be taped with moisture-resistant sticky tape.
- Sheets - can be placed on the ground next to each other. If you are using a sheet underlay, we recommend a layer of 200um builders plastic to be installed above or below it to prevent subfloor moisture from rising upwards.