July 12 2015 0comment
Walnut Barcelona

Wood Flooring Installation Plywood System

The installation of wood flooring using plywood system is one of the best methods that Loiseau Flooring use to provide solid feeling when you step on it. This installation system is suitable for prefinished wood flooring either prefinished solid wood flooring or engineered timber flooring.

Installer/Owner Responsibility

Carefully inspect ALL the timber flooring material prior to installation for defects. Materials installed with visible defects are not covered under warranty by any manufacturer. Remember that wood is a natural product that can vary in colour, grain, and contains natural characteristics that varies from plank to plank and is to be expected. Most of the time, manufacturer do not warrant against these natural variations from plank to plank or variations from sample to plank. If you are not satisfied with the wood flooring prior to installation, simply return the cartons to your dealer for a full replacement. Accepting or rejecting the material must be done on full shipment of quantities only, not carton by carton or plank by plank. We urge you, as the final inspector to inspect for proper colour, finish, style, and quality PRIOR to installation. Verify that the timber flooring is the correct material. Care should be taken at this time to remove or repair particular characteristics you do not desire. Manufacturer declines responsibility for any costs incurred when plank(s) with visible defects have been installed.

Pre Installation & Jobsite Conditions

It is the installer/ owners’ responsibility to ensure that the jobsite conditions and jobsite subfloor are environmentally and structurally acceptable prior to the installation of any hardwood flooring. The manufacturer declines any responsibility for failures or deficiencies of hardwood flooring resulting from or related to sub-floor, subsurface, or job-site environmental conditions. All substrates must be clean, flat, dry, and structurally sound.

Subfloors must be clean and free of dirt, curing compounds, sealers, drywall mud, paint, wax, grease, urethane, or other materials that may affect the integrity of the flooring material or adhesives used to install the flooring

All subfloors and subfloor systems must be structurally sound and must be installed following their manufacturer’s recommendations. Local building codes may only establish minimum requirements of the flooring system and may not provide adequate rigidity and support for proper installation and performance of a hardwood floor. Whenever possible install the planks perpendicular to the floor joists for maximum stability. Our warranties DO NOT cover any problems caused by inadequate substructures or improper installation of said substructures.

Test moisture content for concrete slab and wood flooring using moisture meter. The moisture content of the concrete slab should not exceed 5½%. If it exceeds these limits, DO NOT installs the flooring. The moisture content of the wood should be within 12% ± 2%.

It is the Installer/Owner responsibility to ensure that the conditions are acceptable prior to the installation of the hardwood floors. The manufacturer declines any and all problems with the hardwood flooring that are related to or attributed to improper jobsite conditions.

Assessing the Concrete Slab

Timber floors may be laid on plywood over a concrete slabs. This guideline covers installation of T & G flooring on plywood over concrete. Prior to installation it is necessary to ensure the concrete is sufficiently level to accept the system. Where undulations exceed 3 mm in 1500 mm, a concrete topping or levelling compound should be applied. Slabs on ground should be constructed with a continuous under slab vapour barrier (e.g. 0.2 mm thick polyethylene). Timber floors should not be installed until concrete slabs have moisture content less than 5½% (generally achieved after slabs have cured for approximately 4-6 months). Various methods are available to test the moisture content of concrete including resistance meters, capacitance meters and hygrometers.


Plywood underlay material need to be at moisture content within a few percent of the flooring at the time of installation.

Installation of flooring should not occur until other construction activities, particularly wet trades, are complete. The building should be roofed and enclosed with the temperature and humidity as close as possible to the expected in-service conditions. Expansion gaps of min 8mm to 12mm should be provided at all walls and other fixed obstructions, which are parallel to the run of floor boards.

As an added protection against moisture from the slab or minor building leaks, a 1.0 mm (or minimum 0.2mm) thick polyethylene membrane over the slab is recommended. The polyethylene should be lapped by 200 mm, taped at the joints and brought up the walls above the top of the flooring. The polyethylene is then covered by the skirting. Note that fixings of plywood underlay through the polyethylene is not considered to be an issue.

Plywood underlay should be structural grade, a 12mm (or minimum 9mm) thick. Sheets may be installed at 45° to the direction of the strip flooring with a 5mm gap between sheets or in a brick pattern and a 10 mm gap to internal and external walls. Most people prefer to use brick pattern because 45 º directions install method involve high wastage hence will increase the installation costing. Various methods of fixing are used with nailing and drive pins being the most common.

When staple fixing at close centres is being used, provide a cushion of polyurethane flooring adhesive between the two floors to minimise possible squeaks. This is achieved by using continuous bead of adhesive at 90° to board length, midway between fixing points. Where polyurethane flooring adhesive is used to provide much of the fixing, staples may be spaced up to 450 mm apart.

Floor Protection During Construction

Always protect the surface of the installed flooring during construction by laying a quality rosin paper or other paper that will allow the floor to breathe like corrugated paper, taping it to the baseboards. Never use plastic or polyethylene sheeting to cover the floor since they will trap moisture that will damage the flooring.

Safe Working

Working with timber produces dust particles. Protection of the eyes, nose and mouth when sanding, sawing and planning is highly recommended. Refer to tool manufacturers for safe working recommendations for particular items of equipment.

Disposal of Offcuts and Waste

For any treated timber, do not burn offcuts or sawdust. Preservative treated offcuts and sawdust should be disposed of by approved local authority methods.