Repairs to Timber Floors
Firstly, it needs to be considered that there has been a tradition of solid timber flooring in houses being repaired. Old floors of perhaps 20 or 50 years have often had repairs for many reasons including squeaks, termite damage or water damage. Timber is a remarkable building material where such repairs can be made and also the surface refurbished to look like new again. In more recent years we have seen many changes to the timber flooring industry with products such as engineered flooring, laminate flooring and bamboo flooring. Although solid timber floors are always fixed to their subfloors, engineered or bamboo flooring may be fixed or floated, and laminate is always floated. A floated floor is where boards are fixed to each other, not the subfloor, forming ‘rafts’ that are connected by movement trims. In a similar tradition to solid timber flooring, techniques have been developed where products other than solid timber, irrespective of whether they are fixed or floated can also be repaired. A substantial benefit of purchasing a ‘timber floor’ is that it can often be repaired if need be, and that this is an accepted part of the industry. However, it is also important to be aware of the acceptable repair methods and noting that such repairs increase the life of the floor, without the same cost and inconvenience of replacing it. If re-sanding and coating is needed, it should also be accepted that there will be some reduction in the life of the floor, this is the nature of the product, but with the benefit that a refurbished floor will look like new again. This information sheet considers some of the more common repair methods acceptable to the industry. It covers repairs to solid timber floors as well as the other flooring types that can be either fixed or floated.
Repairs to solid timber floors
The two more significant areas of repair for solid timber floors are board replacement, and resanding and coating, although there are also many minor repairs that may also be carried out. At times an individual board may become damaged and be in need of replacement. A feature such as a gum vein beneath the board surface may have weakened the board causing it to fracture. A problem that nobody has specifically caused, with such an instance shown in the photo. If this or similar was to occur, then with care and skill the board can be removed, and a new board inserted. The new board does need to be modified and extra adhesive used, at times with blocking beneath and top or face nailing from above. However, a neat repair is achievable. In some instances, the replacement board may be resanded and coated prior to the whole floor area being cut back and coated. In other instances, there may be a need to sand the whole floor back to bare timber before coating.
In other situations, it is an area of flooring that needs to be replaced. This could be due to localised water damage or perhaps termite damage to an area of a floor. In such cases the new flooring is ‘toothed’ into the existing flooring, to provide staggering of board ends but at times end joints will be a little closer than in other areas of the floor. But again, with care, the repair will blend in with the remainder of the floor. One consideration is however, that the replacement flooring needs to be close match in terms of colour and features present. This is easier to achieve with some species than others. It should be considered ‘normal’ that during the life of a floor, it will be resanded and coated. But also note that when some have said their floor was resanded and coated, it has actually only had the coating ‘cut back’ prior to recoated. This can be done if the coating has not worn through to bare timber and with this process, there is no reduction in the life of the floor. When a floor ages and has perhaps been recoated several times, it can become quite dark and for this reason it is sanded back to bare timber to make it look like new. If the floor is flat and even in appearance, the resanding is just enough to remove the coat and may only remove 0.5 mm or so of timber. Traditional 19mm thick flooring has 6mm of timber above the tongue and it is accepted that up to 1.5mm of timber can be sanded off during the initial sanding and for the floor to be considered a new floor. But floor life is also related to installation method, with those floors direct to joists or on battens, not being able to be sanded as much as those that are fully supported beneath. Owners need to be aware that there are always risks when a floor is nearing the end of its service life and should that time come from standard sanding practices, it is not the fault of the sanding contractor, noting that they had been presented with a floor near the end of its life. At times, the remaining life can be checked (but still with some uncertainty) and note that it is the owner’s or insurance company’s decision whether sanding can be attempted or whether they would rather have the floor replaced. As repair or refurbishment through sanding necessitates some loss of life, such loss of life needs to be accepted by the owner or those requesting that the work be done.
Repairs to other floors fixed to subfloors
It is mainly engineered floors that are adhesive fixed to a structural subfloor, although some strand woven bamboo floors are also adhesive fixed. These products are usually pre-finished in the factory but also undergo repair when possible. The main forms of repair are board replacement, injection to address drummy boards and re-sanding and coating. Other repairs such as repairing chips with wax filler or re-adhering a lamella are also undertaken, but are less common. As both these products are adhesive fixed over a structural subfloor, there is little change in board width under higher humidity conditions. Due to this it is not uncommon to remove and replace boards either individually, or for an area of flooring to be replaced. The board to be replaced is carefully cut out and the new board inserted. This requires some modification to the jointing system, however, as the boards are adhesive fixed this does not cause any problems. Some care is needed as different batches of product can differ to a degree in colour tones and as a floor ages the colour also changes. However, in many instances when a board is replaced, any difference to the rest of the floor is minimal and does not catch the eye. The sound when walking on an adhesive fixed engineered or bamboo floor with hard foot ware can often differ within and between boards and when hollow sounding, these areas are referred to as drummy boards. Some drumminess is not uncommon in floors and often needs no attention. However, if related to adhesion or in a location where the sound becomes annoying, it is possible to inject adhesive or coating through the board to deaden the hollow sound and improve adhesion. The small hole is then filled and with care blends in with the floor. If considering repair by sanding and coating, it needs to be considered that not all engineered products have a lamella that is sufficiently thick, and many contractors would not sand if the lamella is thinner than 2mm. Note that at times the lamella on some boards may not be at its nominal thickness. Aspects such as bevelled edges and brushed or textured surfaces along with coloured finishes, can also influence what can be achieved, and therefore questions need to be asked regarding what can be done and the expected outcome. Bamboo floors have been successfully resanded and coated but as bamboo is very hard and fibrous, it requires certain skills. Often a full clean of the surface and added coats or polishes can revitalise such floors. If recoating these floor types, that have been factory prefinished, specific primers have been developed to ensure adhesion of the new coat. Engineered flooring with hard wax oil can also be revitalised with further application of the oil.
Repairs to floated floors
In floated floors of engineered, laminate and bamboo, many products have glueless locking systems that join board edges and ends. However, with some engineered and bamboo flooring, a T&G board profile similar to solid timber flooring is used. Generally, it would be expected that boards with the glueless locking system are easier to repair. Floated floors will tend to experience greater movement (shrinkage and swelling) than adhesive fixed floors and problems with the floor not being provided with sufficient expansion allowance and control joints occurs. In many instances, boards can be unlocked and cut back to reinstate the expansion allowance, or control joints can be inserted into the floor. Note that such joints in a floated floor are not an option and when needed must be added for the floor to perform adequately. In terms of board replacement, this is easier if the floor has a glueless locking system and when boards are a set length. With engineered flooring and bamboo there is likely to be more colour change with time and this becomes a consideration if replacing a board. But also note that individual boards have also been cut out of floated floors, particularly if they have the more traditional T&G profile. Also note that modifications are needed to the jointing system to enable the new board to be inserted. The new board is glued to the surrounding boards and not to the subfloor, as it is a floating floor. With the right skills such repairs have provided long term performance and where such repairs do not catch the eye. Laminate flooring is not a product that can be sanded as it has a décor layer with the appearance of wood but is not wood. At times floated engineered and bamboo floors have been successfully resanded to bare timber and recoated, and the same considerations as outlined in the above section apply.