How to Install SPC Flooring: A Complete Installation Guide
Tools and Materials Needed for SPC Flooring Installation
Essential Installation Tools
Tapping block and pull bar specified for the locking system.
Spacers for the expansion gap.
Saw for cutting planks, and a jigsaw or oscillating tool for door frames and pipes.
Measuring tape, square, pencil and a straightedge.
The moisture test method specified for the subfloor type.
Soft broom, vacuum and a damp cloth.
Knee pads, gloves and eye protection.
Flooring Accessories and Trims
Underlayment, where the product does not have an attached backing.
Moisture barrier, where the product and the subfloor require one.
Transition strips for doorways and changes of flooring.
Skirting board or baseboard for the perimeter.
Pipe collars and end caps for the finishing.
The tools and the accessories are the ones specified for the product. Different locking systems use different tapping tools, and a tool that works on one product can damage the joint on another. This page is a step-by-step installation tutorial; the engineering acceptance criteria and the specification requirements for a commercial project are covered on the commercial SPC flooring page. Every requirement in this guide is subject to the installation instructions supplied with the product, which take priority over a general guide.
Installation Requirements to Confirm Before You Start
The six items below are the ones to confirm before the first row is laid. Each is confirmed from the product's installation instructions and the site conditions, and none is a fixed figure that applies to every product.
Subfloor flatness: the tolerance for the product, the measuring method, and whether levelling is needed.
Subfloor moisture: the test method for the subfloor type, and the limit stated for the product.
Underlayment: whether the product has an integrated backing, and whether an additional underlay is permitted.
Expansion gap: the size stated for the product, and whether an intermediate joint is required for the room length.
Acclimation: whether the product requires it, and under what conditions.
Underfloor heating, if present: compatibility and temperature limits from the installation instructions and from the heating system.
Prepare the Subfloor Before Installing SPC Flooring
Concrete Subfloor Preparation
The slab must be sound, dry and flat within the tolerance stated in the product's installation instructions. Remove dust, paint, adhesive residue and loose material; repair cracks and hollow spots; and level or grind the floor where the flatness is out of tolerance. Where the slab is new, the curing period stated for the product applies. An SPC core is rigid, but it does not correct an uneven slab: an out-of-tolerance subfloor stresses the locking system and opens the joints.
Plywood and Wood Subfloor Preparation
The timber subfloor must be sound, firmly fixed and flat within the product's tolerance. Replace loose or damaged boards, fix squeaks, and check for any sign of rot or insect damage. Where the boards are uneven, the subfloor is levelled with a suitable underlay board or a levelling compound before installation. The planks are laid across the boards where the instructions require it.
Installing SPC Flooring Over Existing Tile
SPC can be installed over existing tile only where the tile is sound, firmly bonded, flat within the product's tolerance and dry, and where the manufacturer's installation instructions permit it. Loose or hollow tiles are removed, and deep grout lines may need an underlay board to bridge them, subject to the product instructions. The finished height and the door clearance are checked before installation.
Moisture and Flatness Checks
The subfloor moisture condition is tested before installation, and the test method depends on the subfloor type: a concrete slab is tested with the method specified for concrete, a timber subfloor with the method specified for timber. The readings are compared with the limits in the product's installation instructions for that subfloor type. A concrete slab that looks dry on the surface can still contain moisture, which is why the test is done rather than judged by eye.
Flatness is measured with a straightedge at several points and in both directions, and the readings are compared with the tolerance stated for the product. Flatness and moisture are checked together, because both determine whether the installation can proceed as planned.
How to Install SPC Flooring Step by Step
Plan the Layout and Installation Direction
Before the first row, plan the direction, the starting point and the width of the first and last rows. Laying the planks parallel to the main window or the longest wall is a common choice, and the direction is decided before installation because it cannot be changed afterwards. Measure the room and check that neither the first nor the last row will be too narrow to work with; where the last row would be narrower than the product instructions permit, adjust the width of the first row instead.
Install the First Row
Start in a corner with the tongue side facing the wall, and use spacers to hold the expansion gap. Place the first plank, connect the next plank along the long edge, and check that the joint is tight and flat. Check the first row for straightness with a straightedge, because the rest of the floor follows it. A first row that is not straight shows as an open joint at the far side of the room.
Connect the Click-Lock Planks
Connect the planks with the locking method specified for the product, using the tapping block and pull bar specified for the locking system. Tap on the block rather than on the tongue. The insertion angle and the technique follow the manufacturer's instructions for that locking system; a technique that works on one product may damage another. An SPC core is rigid, so the profile is less forgiving of an out-of-tolerance subfloor and of grit in the joint than a softer core, and the joint is checked as the row progresses rather than at the end.
Stagger the End Joints
The end joints are staggered from row to row as specified, so that the joints do not line up across the floor. Cut the first plank of each new row to produce the stagger, and keep the cut ends against the wall rather than in the middle of the room where possible.
Cut Planks Around Door Frames and Pipes
Door frames and architraves are undercut so that the plank slides underneath, rather than cutting the plank around the frame. Pipes are drilled with a hole slightly larger than the pipe, and the plank is cut through the centre of the hole so that it fits around the pipe; a collar covers the cut afterwards. The expansion gap is left around the pipe as for a wall. At a wall corner or a change of direction, the plank is cut to the corner with the expansion gap maintained on both walls, and the corner joint is checked for a tight fit.
Install the Final Row
Measure the width of the last row and cut the planks to that width, allowing for the expansion gap against the wall. Use the pull bar to close the joint where the planks are too close to the wall for the tapping block, and check that the last row is straight and the expansion gap uniform.
Fit Skirting Boards and Transition Strips
The skirting is fixed to the wall rather than to the floor, so that it covers the expansion gap without restricting the floor's movement. Transition strips between rooms and between flooring types are fixed to the substrate rather than to the plank, so that they do not restrict the floor. The trims and the thresholds are checked for a clean finish at the doorways.
SPC Flooring Expansion Gaps and Underlayment Requirements
The expansion gap at the perimeter and at fixed objects is stated in the installation instructions for the product, and its size depends on the product and on the room rather than being a single figure for every floor. A floor laid tight against a wall has nowhere to move, and the movement appears at the joints instead. Where the room is long, the installation instructions state whether an intermediate expansion joint is required; a maximum continuous length is not a single figure for every product.
The underlayment is the one specified for the product, and three situations should be kept apart. Where the product has an integrated IXPE or EVA backing, an additional underlay is not added by default, because it can change the behaviour of the locking system and may affect the warranty. Where the product has no integrated backing, whether an additional underlay is permitted is stated in the installation instructions for the product. Where an underlay is used, its thickness, density and compression behaviour are matched to the locking system, and the underlay is not used to compensate for an uneven subfloor.
SPC Flooring Installation on Different Subfloors
The preparation of concrete, wood and tile subfloors is set out in the section above. This section states only the requirement that is specific to each subfloor once it is prepared.
On concrete, a moisture barrier is used where the product and the subfloor require it, and the slab moisture reading is recorded against the limit for the product before the barrier is laid.
On plywood and wood, the plank direction across the boards follows the installation instructions, and the subfloor moisture reading is recorded against the limit for timber.
On existing ceramic tile, the installation is permitted only where the manufacturer's instructions allow it, and the finished height and door clearance are checked before the first row.
Common SPC Flooring Installation Problems and Solutions
Four problems account for most installation callbacks: joint separation, buckling after installation, popping or squeaking sounds, and edges chipping during installation. Each is caused by a small number of things, and each is checked in the same order: the expansion gap, the subfloor flatness and moisture, the locking engagement and the condition of the profile.
The causes, the prevention and the checks for each problem are set out in detail on the SPC flooring installation mistakes page; this section gives the overview only.
How to Inspect SPC Flooring After Installation
Walk the floor and check for movement, hollow sounds and uneven joints. Check the expansion gap at the walls, around door frames and at pipes, and confirm that the skirting and the transition strips are fitted without restricting the floor. Check the transitions and the door frames for a clean finish. Clean the floor as stated in the care instructions and check for marks left by installation, and keep the installation records, the product labels and the spare planks for later repairs.
Frequently Asked Questions
1. Does SPC flooring require glue?
The product is installed as a floating click-lock floor without adhesive to the subfloor. Whether a glue-down installation is permitted is stated in the installation instructions.
2. How flat must the subfloor be?
The tolerance is stated in the installation instructions for the product, and it is measured with a straightedge at several points. A single figure is not a rule for every product.
3. Can you install SPC flooring on concrete?
Yes, where the slab is dry, sound and flat within the product's tolerance, the moisture condition is tested with the method specified for concrete, and a moisture barrier is used where the product and the subfloor require one.
4. Can you install SPC flooring over existing tile?
Only where the tile is sound, firmly bonded, flat within the product's tolerance and dry, and where the manufacturer's installation instructions permit it. Loose or hollow tiles are removed first.
5. Can SPC flooring be installed over plywood?
Yes, where the timber subfloor is sound, firmly fixed and flat within the product's tolerance, and the subfloor moisture is tested with the method specified for timber.
6. Do you need underlayment under SPC flooring?
It depends on the product. Where the product has an integrated backing, an additional underlay is not added by default. Where it has no integrated backing, whether an additional underlay is permitted is stated in the installation instructions, and the underlay is not used to correct an uneven subfloor.
7. Which direction should SPC flooring be installed?
Laying the planks parallel to the main window or the longest wall is a common choice. The direction is decided before installation, and the width of the first and last rows is checked at the same time.
8. How do you cut SPC flooring around door frames?
The door frame and architrave are undercut so that the plank slides underneath, rather than cutting the plank around the frame. The expansion gap is left at the frame as for a wall.
9. How much expansion space does SPC flooring need?
The size is stated in the installation instructions for the product and depends on the product and the room. A fixed figure is not a rule for every product, and where the room is long the instructions state whether an intermediate joint is required.
