The process in which Kustom Timber suggests laying flooring for glue and staple/nailing installation.
| Glue-Down Process |
| Staple/Nail Down Process |
| Over Timber Battens |
| Floating Floor Method |
| Essential Tips |
| Solid Timber Flooring Installation |
Glue-Down Process (For engineered boards)
Prior to starting the process of gluing the engineered flooring directly to the subfloor, the subfloor is to have been prepared in accordance with the ‘Subfloor Preparation’ section above. This includes aspects relating to the subfloor being sufficiently clean, dry, sound and flat to accept the flooring. It also outlines that compatible products, in terms of levelling compounds, moisture vapour barrier and adhesives, must be used and be suitable for the installation of engineered flooring. Adhesives are to be either polyurethane or polymer timber flooring adhesives.
With adhesive fixed floors, glue ridge height is important and therefore the trowel to be used needs to be that indicated by the adhesive manufacturer for this method of installation, and the adhesive needs to be applied as a full trowel bed in accordance with the adhesive manufacturer instructions. Generally, the trowel is held at a 45-degree angle to the subfloor to obtain the correct ridge height and spread rate.
When the wall from where the installation will start has been chosen, snap a chalk line or use a laser to find out how straight the wall is. Note that the starting point is important to ensure that visual effects of non-parallel and bowed walls are minimised and this also necessitates that boards cut adjacent to walls remain as wide as possible. Floors are usually laid lengthwise down hallways and consideration needs to be given to this, to see that the floors in installed parallel to hallway walls. The location of the control and expansion joint(s) also needs to be considered.
The appropriate positioning of the first row of boards is therefore essential in the glue-down process as it dictates the installation of the whole floor. When laying this first row, you should always use wedges or blocks, or fix the first row, but also creating an expansion gap of at least 3mm along the wall (and noting that a similar gap is to be provided to the walls at board ends).
Make sure that this first row of boards is completely aligned and tight at end joints and note that that the tongue side of the board is away from the starting wall. From the starting wall adhesive is spread in an area that is approximately 300mm (or 2-3 boards) wide along the full length of the wall. It is best to measure out the correct distance and use a chalk line to make sure you don’t apply the adhesive too far ahead.
Install the board at a 45-degree angle. Engage the side (edge) tongue and press into the adhesive, sliding lengthwise until the end tongues fully engage. Make use of a hammer and tapping block to tighten the fit and take care not to damage the boards. Continue with this method until all adhesive applied to that area has been covered. For subsequent rows, (making sure not to utilize board offcuts that are less than 450 mm in length so as to avoid clustering of end joints) and to avoid clustering of end joins, unless using for starters and finishing boards.
Be careful to always ensure that there is enough adhesive on the subfloor to cover the whole board and make sure that all boards are straight to avoid improper installation alignment at the end of the job. Boards lengths should be staggered and with use of different length starting boards to produce a more random laying effect.
The Kustom Timber preferred method and look is a random mixed appearance. Continue with this process until all the floor is laid, noting that the boards along the wall opposite the starting wall will most likely need to be cut, and ensuring that expansion gap allowances are provided to the full perimeter of the floor.
While you want to make sure that contact is made between the adhesive and the boards, avoid hammering the boards on the top surface. In some instances, you will need to use weights to properly set the boards into the adhesive on the subfloor. Once the adhesive has cured the weights may be removed. Refer to adhesive manufacturer instructions for appropriate allowances for curing times.
If during laying some adhesive has found its way onto the board surface it is necessary to clean it off as quickly as possible using products provided by or recommended by the adhesive manufacturer. Care is needed so as not to permanently mark the boards and the longer the adhesive is on the board the more difficult it is to remove without trace.
Equipment, traffic, and furniture items should be kept off the flooring for at least 24 hours to make sure that the adhesive is firmly set.
Finishing Off
Once the glue is sufficiently dry and the laying is complete, all spacing wedges are to be removed. At this point, make use of fillers to cover any visible gaps or joints along the board edges or at the ends where two boards meet. Make sure to match the filler colour to the boards. Test the filler on a leftover piece of board to ensure compatibility. Skirting boards and scotia can then be fixed to the wall or cabinets, noting that they are never directly fixed to the installed floor.
Staple/Nail Down Method (engineered products)
The subfloor is to be prepared in accordance with the ‘Subfloor Preparation’ section above and when using this method a subfloor fixed to joists will be either plywood (minimum 15mm thick) or particleboard (minimum 19mm thick) or when fixed to a concrete slab either 12mm or 15mm thick plywood.
Plywood fixing to the slab over a 200µm plastic moisture vapour barrier is by spike type fixing as used with solid timber floors. Therefore, 4 rows by 5 with 15mm thick plywood or 4 rows by 7 with 12mm thick plywood. When the wall from where the installation will start has been chosen, snap a chalk line to find out how straight the wall is. Note that the starting point is important to ensure that visual effects of non-parallel and bowed walls are minimised, and this also necessitates that boards cut adjacent to walls remain as wide as possible. Floors are usually laid lengthwise down hallways and consideration needs to be given to this to see that the floor in installed parallel to hallway walls.
The location of the control and expansion joints also needs to be considered.The appropriate positioning of the first row of boards is therefore important as it dictates the installation of the whole floor. When laying this first row, you should lay it a few rows away from the wall and include a 10mm expansion allowance at the wall, to be covered later by the skirting. A chalk line in this location and made parallel to the chalk line at the wall, can have a holding board (say 80 x19mm) fixed to it to ensure the first row remains straight. The correct shoe for the stapler, based on the thickness of flooring, needs to be used and with a spare board, compressor pressure set and then adjusted to achieve correct fixing.
The boards can then be aligned and fixed to minimise any gaps at board edges and adjoining ends. Fixings are to be no closer than 100mm from board ends and with spacings no greater than 450mm. The rows of boards at the starting wall can be installed at the time of the last rows being installed (after removing the holding board). These outer boards will require face nailing, as secret fixing in not possible close to walls. The final board opposite the starting wall will also need to be cut lengthwise to fit (after taking perimeter expansion allowance into account) and if narrow in width it should be adhesive, as well as face fixed.
Specific site considerations may require specific solutions outside the general guidelines above.
Finishing Off
At this point, make use of fillers to cover any visible nail holes, gaps or joints along the board edges or at the ends where two boards meet. Make sure to match the filler colour to the boards. Test the filler on a leftover piece of board to ensure compatibility. Skirting boards and scotia can then be fixed to the wall or cabinets, noting that they are never directly fixed to the installed floor.
Over Timber Battens (For 21mm thick engineered boards)
The subfloor is to be prepared in accordance with the ‘Subfloor Preparation’ section above and when using this method, battens need to be kiln dried, minimum 60 x 19mm high density hardwood or 70 x 35mm medium density hardwood. Fixing of the battens to the slab (with a 200 µm plastic moisture vapour barrier beneath) is at up to 450mm spacing with hand driven spike type fixings.
A combination of polyurethane or polymer timber flooring adhesive along the top of the battens and secret stapling is used to fix the floorboards.
When the wall from where the installation will start has been chosen, snap a chalk line to find out how straight the wall is. Note that the starting point is important to ensure that visual effects of non-parallel and bowed walls are minimised, and this also necessitates that boards cut adjacent to walls remain as wide as possible. Floors are usually laid lengthwise down hallways and consideration needs to be given to this to see that the floor in installed parallel to hallway walls. The location of the control and expansion joints also needs to be considered.
The appropriate positioning of the first row of boards is therefore important as it dictates the installation of the whole floor. When laying this first row, you should lay it a few rows away from the wall and include a 10mm expansion allowance at the wall to be covered later by the skirting. A chalk line in this location and made parallel to the chalk line at the wall, can have a holding board (say 80 x19mm) fixed to it to ensure the first row remains straight. The correct shoe for the stapler, based on the thickness of flooring, needs to be used and with a spare board, compressor pressure set and then adjusted to achieve correct fixing. A 6 to 10mm wide bead of adhesive is applied to the top surface of the batten prior to secret stapling the boards in place at each batten crossing, and ensuring boards are tight to minimise any gapping at board edges and ends.
The rows of boards at the starting wall can be installed at the time of the last rows being installed (after removing the holding board). These will require face nailing with two 2.2mm diameter nails at each joist crossing, as secret fixing in not possible close to walls. The final board opposite the starting wall will also need to be cut lengthwise to fit (after taking perimeter expansion allowance into account) and if narrow in width it should be adhesive fixed to the previous board before face fixing. Specific site considerations may require specific solutions outside the general guidelines above.
Finishing Off
At this point, make use of fillers to cover any visible nail holes, gaps or joints along the board edges (engineered only) or at the ends where two boards meet. Make sure to match the filler colour to the boards. Test the filler on a leftover piece of board to ensure compatibility. Skirting boards and scotia can then be fixed to the wall or cabinets, noting that they are never directly fixed to the installed floor.
Floating Floor Method Installation (For engineered boards)
Before installation, it is important to understand that the groove side of the board will face the wall from where the installation will start. In addition, you should also avoid tapping the groove side to seat boards – only tap the tongue side of the board and use a tapping block. Use spacing wedges regularly along the length of the starting wall to make sure that there is an expansion gap of approximately 10mm between the first row of boards and the wall.
The subfloor is to be prepared in accordance with the ‘Subfloor Preparation’ section above. Check that the underlay has an integral plastic moisture vapour barrier of 200µm, and if not, slab moisture vapour protection as outlined above for slabs or timber subfloors (as applicable) is to be provided. The underlay is rolled out and often has a lapped joint with adhesive tape to maintain moisture vapour protection. Instructions provided by the underlay manufacturer are to be followed. Note that the maximum underlay thickness to be used is 10mm.
When the wall from where the installation will start has been chosen, snap a chalk line to find out how straight the wall is. Note that the starting point is important to ensure that visual effects of non-parallel and bowed walls are minimised, and this also necessitates that boards cut adjacent to walls remain as wide as possible. Floors are usually laid lengthwise down hallways and consideration needs to be given to this to see that the floor in installed parallel to hallway walls. The location of the control and expansion joints also needs to be considered.
You should begin the laying of the flooring by starting at a corner of the starting wall. Start the next row with a piece left over from the previous row or with a board that is at least 450mm shorter or longer than the first board in the previous row. The end joints of the adjoining boards should be staggered by at least 450mm. Do not install the boards in a brick like pattern as random end joints is considered to provide a more pleasing appearance.
As boards are laid, apply cross-linked D3 PVA wood adhesive along all board joints (including end joints). The adhesive is applied in a continuous bead to the top horizontal face in the groove. Note that the bead must be continuous, because if broken, it can lead to squeaks and weakness in the jointing system that can cause board joints to separate. The adhesive also provides some moisture protection to board joints. Hence, it is important to apply the adhesive correctly for a number of reasons. Any excess adhesive is to be immediately wiped off with a damp cloth. If you notice that the boards are not fitting well, open a gap between boards as excess adhesive can hinder the boards from joining properly (vacuum effect).
Use a rubber mallet and a tapping block to press the first board of the next row into position. Avoid hitting the board directly with a mallet as this will increase the possibility of damaging the board and the possibility of edge splintering after completion.
The laying continues row by row until the opposite wall is reached. In most cases, the final row will not be a full board width, so the boards will need to be trimmed along their length and noting that the 10mm expansion gap to the wall needs to be maintained (tongues removed if present). When laying the last row, apply the glue in the groove before putting the boards into place with wedges and suing a spacing bar. With this method, use protective blocks or flooring offcuts to protect the wall and boards from spacing bar damage. Place the floorboards as low to the wall as possible and use the spacing bar to force the boards into position. Once all the boards are fitted and the adhesive is adequately dry remove all wedges.
Finishing Off
At this point, make use of fillers to cover any visible gaps or joints along the board edges (engineered only) or at the ends where two boards meet. Make sure to match the filler colour to the boards. Test the filler on a leftover piece of board to ensure compatibility. Skirting boards and scotia can then be fixed to the wall or cabinets, noting that they are never directly fixed to the installed floor.
Essential things to remember when laying floors
- It is crucial that all adhesive residue is immediately removed the moment you lay each board. Use a solvent that is suitable to the adhesive (as indicated by the adhesive manufacturer) or flooring wipes. To avoid any discrepancies in the colour/finish, it is always important to test the solvents first on an off cut to make sure that the solvent won’t affect the appearance of the board.
- If further works are to be undertaken after the floor is installed, then the floor should be protected using a foam underlay with a thickness of 2mm, and 3 to 4mm thick MDF sheeting, appropriately taped at all joints and noting that all the floor to the walls is to be covered (this protects the whole floor and ensures not colour variation occurs between covered and uncovered).
- Avoid applying tape to the floor or getting plaster dust on the finished floor. Moisture can cause the plaster dust to set in the lower grains of the timber, making it very difficult to remove. In addition, it is also in your best interest to not mop any dust. If dust is present on the surface floor, use a vacuum cleaner to remove it.
- With some engineered flooring, an additional coat of Neutral Oil Care, Hard Wax Oil, or Lacquer is highly recommended to be applied upon the completion of the installation. This is an excellent way of not only providing your floor with an exquisite finish but also prolonging the need for maintenance of the floor. A sales representative can provide you with advice as to which product is best for your chosen floor.
- As per instructions, clean your floor with a lacquer soap, LOBA floor cleaner or a WOCA Natural Soap on a monthly basis. For further information, please head on over to our ‘Maintenance and Cleaning Guide’.
Solid Timber Flooring Installation
Before Installation check
- Transportation has not compromised or damaged the boards • The subfloor is at the correct moisture content
- The subfloor is ready and suitable for adhesive bonding
- Additional expansion has been allowed for in any floors greater than 4 meters wide
- Appropriate acclimatisation has been allowed for in dry or humid climates
- The internal environment of the dwelling is suitable for installation
- The slab moisture content is below 5.5% and within the flatness tolerance
- A moisture barrier has been applied followed by black plastic (joints taped) and brought up behind the skirtings.
- Structural 15mm plywood has been installed with 6mm gaps and 28 concrete pins (50mm) per sheet
- Full bed of polyurethane adhesive to be trowelled across the plywood before laying solid timber flooring.
- 25mm long fixings to be used to secret nail the hardwood flooring every 250mm
- The subfloor space must be adequately dry with vents evenly spaced with 7500mm2 free area per meter of wall
- The joists must be flat and level.
- 15mm structural plywood or 19mm particleboard must be screwed and glued to joists. Flooring to be installed perpendicular to joists.
- Full bed of flexible polyurethane adhesive to be trowelled out before laying planks of hardwood flooring.
- Fixings must be 25mm long and spaced every 250mm