Hessian-backed carpet should always be fitted on top of underlay. It can be laid on almost any type of subfloor (concrete, hardboard, etc.) For the best finish, hessian-backed carpet needs to be stretched, using a knee-kicker, and fixed around the edges of the room with gripper rods. Hessian-backed carpet is usually more expensive than foam-backed carpet, but should last longer.
Step 1 – Fixing Gripper Rods
Gripper rods are lengths of flat wood (or sometimes metal) with small, sloping teeth all over the top face. They are used to hold the stretched hessian-backed carpet at the edges of the room. Nail the gripper rods all the way around the edge of the room, with the sloping teeth pointing towards the wall. Leave a small gap between the gripper rod and the skirting, equal to approximately the thickness of the carpet.
Use ring-shank nails which are long enough to penetrate the floorboards, but not so long that they go all the way through, or you risk bursting pipes under the floor. The gripper rods need to be firmly attached, so space them no more than 200mm apart along the length of the rod. If you need to fit the gripper rods around an obstacle such as a door frame, cut small lengths which will allow you to roughly follow the shape.
Step 2 – Laying the Underlay
Roll out your chosen underlay material across the floor, letting it overlap the gripper rods. You can then cut it to size, using a sharp Stanley Knife, by following the inside edge of the rods. Remove any excess underlay and you should be left with a neat, flush finish.
Using a staple gun, staple the underlay to the floorboards to stop it shifting underneath the carpet. Tape any joints in the underlay using masking tape. If laying on a solid concrete floor, use underlay adhesive to stick the underlay down. Ventilate the room and allow the adhesive to dry before continuing.
Step 3 – Laying the Carpet
The carpet should be cut roughly to the size of the room already. If you are cutting the carpet yourself, or if you are having it cut at the store, make sure that you allow for an excess overlap of at least 150mm all the way around. Position the roughly cut carpet on the floor, allowing the overlap to run up the walls. Move the carpet so that the overlap is even on all sides.
Smooth out the carpet as much as you can across the floor. At the corners of the carpet, make small cuts, at right angles, to allow the carpet to sit flat in the corners of the room. Be careful not to cut too far into the corner. Repeat this process to fit the carpet into alcoves or around fireplace hearths, for example. The carpet should now be laying fairly flat over the whole area.
Using a very sharp Stanley knife, trim the excess carpet flush with the base of the wall or skirting boards. In one corner of the room, use a bolster to press the carpet down onto the gripper rods to secure it. You will now need to use the knee kicker to stretch the carpet tight. Work from the secured corner to the adjacent corner. Again, use the bolster to press the carpet onto the gripper rod teeth to secure it. Don’t expect a huge amount of stretch, you are simply pulling the carpet tight.
Return to the first corner and use the knee-kicker to stretch the carpet towards the other adjacent corner. Secure this corner as before. Return to the first corner again. Now stretch the carpet diagonally across the room to the only unsecured corner (assuming it is a square or rectangular room) and use the bolster again to attach the backing to the gripper rods. You now need to work your way along each wall, pressing the edge of the carpet onto the gripper rods all the way around the room. Use the knee-kicker to stretch out creases if required.
1 – If the carpet needs to be repositioned or lifted for some reason, you should be able to unhook it from the gripper rods as required. You may need to use a knee-kicker to take up some of the tension before unhooking.
2 – If lengths of hessian-backed carpet need to be joined, it is probably best to get a professional in. This is a tricky task which requires specialist tools such as a hot seaming iron, seam roller and seaming tape.