Identifying your subfloor
Your subfloor is, literally, the floor beneath your floor. It is the structure over which your new flooring will be installed. The subfloor can be the concrete foundation of your home, or the wood boards or plywood fixed to the floor joists. The decision on which type of floor you can install and the method of installation to use depends on your subfloor.
Some common subfloor types are:
- Concrete or cement
- Plywood – a panel made of thin layers of wood bonded together. The layers have alternating grain directions to add strength
- Particleboard - made from wood particles (wood chips, sawmill shavings, saw dust) bonded together under pressure. Particleboard is a cheaper but less durable alternative to solid wood or plywood subfloors
- Tongue & Groove Floorboards – traditional softwood floorboards
Here’s a quick reference on subfloors with flooring types and installation method used:
|Subfloor||Flooring Type||Installation Method|
|Concrete, Cement||Solid||Nailed onto Battens, Glue-Down|
|Plywood, Tongue & Groove||Solid||Nail-down, Glue-Down|
|Particleboard||Solid ||Nail-down, Glue-Down|
Note: Vinyl floors, carpets, and other existing flooring types are not suitable as subflooring and must be removed. Before installing any type of flooring, it is important that you get down to the solid, flat and dry subfloor.
You will need a clean, flat and dry sub floor. ‘Flat’ means no more than 3mm variation up or down over a 3 metre span.
If you find you have an uneven floor, you can use screed levelling compounds on hard surfaces like concrete or plywood, or you could use a fibreboard underlay to cover a rough surface.
Temperature and humidity readings of environment
Taking a temperature and humidity reading of the internal environment is a recommended step before acclimatising your floor. Keep these readings safe. If future problems do arise, then you will have a good benchmark which you can use to assess the best way to deal with the issue.
Moisture testing and control
Ensuring that your new floor is properly acclimatised to the moisture conditions, temperature and humidity of the room is a vital part of a successful flooring installation.
A close watch on your job sites moisture conditions should be done before, during and after installation. Because environmental conditions greatly affect the behaviour of wood, humidity and temperature should always be controlled to avert potential disaster.
Do It Yourself
While all professional installers are equipped with the more expensive moisture meters, you can perform your own moisture testing using common materials found in your local hardware or supply store.
All you will need are some clear plastic sheets and duct tape to conduct your own moisture testing for concrete subfloors. Cut several small pieces of plastic sheet, approximately 50cm square, and place them on several locations of your job site. Seal the edges with the duct tape and let them sit for 24 to 48 hours. If condensation occurs, you have got some residual moisture problems that will need to be dried out.
To avoid potential problems with moisture a damp proof membrane (DPM) layer of sheet plastic (1000 gauge or more) or Timba liquid DPM is always recommended before installation.
Under Floor Heating
All under floor heating system should be installed and working correctly before any installation can take place. A maximum of 27⁰C should never be exceeded and all heating should be switched off at least 2 days before you install a new floor. Once installed the heating must only be used in small increases of 2⁰C per day to allow the new wood floor to adapt slowly.
UFH must not be used with Solid hardwood floors.