When and how to use a plywood sublayer?
A floor is made up of several layers. Beyond the surface coating, the solidity and durability of the floor depend on the structure of the house, the joists, the base surface and the sub-floor. When building or renovating the floor, you have to think about each of these layers, because they play a much more important role than one might suspect.
In this article, we will focus more specifically on the different materials used for the underfloor layer. We will first present the main types of sub-planchers available on the market, and then go deeper as to which are better suited depending on the type of coating that will be installed over it.
The base surface
To choose the type of underfloor material you are going to install, you must consider both the coating you have selected and the base surface on which you are going to install. There are four main categories of surfaces :
Panel of large oriented particles ;
Concrete slab ;
The role of the sub-floor
Depending on the type of coating you want to install, you will need to choose a sub-floor that allows you to adapt the surface and create a layer between it and the coating installed above, to ensure that the floor is efficient and resistant. For example, you should avoid your floor being cold, twisted or too wet. Underfloor materials will be able to resolve and prevent most of these problems.
However, you will need to make sure you make the right choices, as some materials do not work with each other.
In summary, the main objectives of the sub-planks are to create a flat surface, to contribute to soundproofing, to protect the base surface and to occupy other functions (all depending on the environment and the type of floor ).
The different types of sub-planks
When choosing your underfloor material, you will have already determined what type of surface is between the joists and the coating of your floor. With this information in hand, you will be able to explore the different models and products of sub-planchers offered on the market. You will quickly notice a wide variety of options.
We separated the different materials according to the main types of floor coverings. However, it is important to specify that you will have to take into account other criteria, in particular in relation to the type of environment in which you install your floor.
For example, if it is a basement or bathroom floor, you will need to make sure to install a underfloor that serves as a vapor barrier.
It should also be noted that some materials are suitable for several of the coatings mentioned. Finally, if you have concerns related to ecology, you will also have to keep this criterion in mind when you make your choice :
Underfloors for wooden floors
Wood is an timeless material, renowned for its resistance and its versatile appearance. There are several types of wooden floor coverings, including frankwood and engineering wood. These floors are made from a wide variety of species. If you would like to know more, here are some articles to consult :
Here are the different types of sub-planchers that you can install under a wooden floor :
The felt underfloor
The felt underfloor is sold in rolls or tiles. Easy to install, its density gives it soundproofing properties.
The rubber underfloor
Rubber is a material that absorbs sound well and resists humidity. More expensive than other materials, however, it is very easy to install.
The foam underfloor
If you are looking for a more ecological material than the two previous options, be aware that the foam underfloor can be recycled. On the other hand, the foam is sometimes less resistant than the other materials. To compensate for the shortcomings and take advantage of the advantages, products combining two materials (foam and rubber or foam with vapor barrier) are available on the market.
The cork underfloor
If the wooden coating is able to breathe well, it will stay in good condition longer. The cork sub-floor allows the floor to be protected, while providing a solid surface for the installation.
The vapor barrier underlay
Frankwood should not be used in very wet parts and in basements. On the other hand, certain types of wood may be suitable for this kind of environment, provided that humidity is not able to accumulate between the floor layers. This is where the interest of installing a vapor barrier underlay comes from. This material can be used in combination with other types of sub-planchers, when the latter do not already come equipped with a protective layer.
Tile flooring sub-planks
All sub-planks must be perfectly straight in order to accommodate the floor covering. That said, this criterion is all the more important when it comes to a tiled floor, because an irregular surface could harm the stability of these.
Here are the most used underfloor materials when installing a tile floor (ceramic, stone or other) :
Fibrociment panels are made from a mixture of wood fibers and cement. Unlike cement panels, they are flexible and less susceptible to cracking.
The desolidarization membrane
Here is a very good quality underhang material, which can be reflected in its price. On the other hand, the disolidarization layer has proven itself and you will generally be entitled to an extended guarantee. Some models are specially designed to accommodate heating floor cables.
The sub-finition of self-tuning cement
This product will often be used when the base surface is uneven. Self-painting cement is a product that can work real little miracles. However, it is not easy to apply. It is therefore strongly recommended to call on the services of an expert.
Sub-planks for vinyl or linoleum floors
Vinyl and linoleum have long had a bad reputation, but technological advances in recent years have made these materials more durable and resistant. On the other hand, the layer of underfloor becomes even more important to ensure the longevity of the coatings.
If you plan to use any of these materials, it is recommended to install a plywood sublayer to provide a stable surface. The plywood should be about 1/4 inch thick.
Sub-planks for laminated floors and floating floors
Photo: Flickr; Floorsmsk
With regard to laminated floor coverings and floating floors, several materials presented in the preceding paragraphs, including foam and rubber, would be entirely suitable options.
Here is a material that has not yet been mentioned :
The acoustic membrane
Laminated floors and floating floors may tend to move. The acoustic membrane can therefore help reduce impact noise and stabilize the floor. This membrane can be installed on a plywood.
Underfloors for carpets
The carpet is less fashionable at the moment, but it is still used in certain environments, including offices and bedrooms. If you are thinking of installing a carpet, you can opt for a foam or rubber underfloor.
Some additional notes about the sub-planchers
This guide is intended to be a general presentation of the sub-planks available on the market, but there are many other materials. In some cases, it is possible to omit the installation of a sub-floor and to place the coating directly on the base surface. However, in most cases, this is not recommended by the experts, as this layer can play an important role.
Also note that certain coatings, in particular laminated floors, sometimes already come equipped with layers of underfloor. In this case, with some exceptions, you will not have to install any other sub-floor.
What about heated floors?
The heating floor is a subject in itself and as we already have several interesting articles on this subject, we will rather put the links towards these :
Install a sub-floor: seek the advice of an expert
We have presented a wide variety of underfloor materials and so we hope we have given you a good overview of the different possibilities. That said, nothing replaces the advice of an expert. When the time comes to renovate a floor, especially if you have to go to the underfloor layer, the specialist will be able to make judicious choices in relation to materials and installation techniques.
Obtain bids for a floor renovation project
SubmissionRenovation.ca can help you with your floor renovation procedures. Speaking of your project, we will put you in free contact with the appropriate resource people. You just have to fill out our form (in just a few minutes) and you can receive bids from companies specializing in floor renovations.