Buying, selling or running a home – everything you need to know about your home and garden!

Floor Repairs

Suspended Timber

Suspended timber floors are by far the most common type of flooring system and have been used for hundreds of years. The floors are supported on joists and sleeper walls in the sub-floor void.

Timber floors are often built and then wedged to ensure that all the joists are level and allow the floor surface to be installed evenly. Problems occur where the wedges work loose and then the floor can become uneven or springy.

Many defects to timber floors are caused by timber and damp problems resulting in rot or woodworm infestation. Through time they cause the deterioration of the timberwork and cause the floor to become springy or fail completely. If this has occurred the damp problem needs to be remedied and then new treated timbers installed as appropriate. The advice of a qualified timber and damp treatment company should be sought and works should have an insurance-backed guarantee.

Solid Concrete

Solid concrete floors and stone floors have likewise been used in houses for hundreds of years; however, they are not free from problems.

Settlement can occur to a concrete floor where the fill material has not been compacted enough. With this defect you often get a gap between the skirting board and the floor that is uneven. You will also see cracking in the concrete slab. Repairs are not always required but when the movement is significant the floor may require breaking up and removing, and a new floor being laid on a suitably compacted material.

Sulphate expansion occurs to concrete floors where the mixture of the concrete is incorrect or where there are other materials used to bulk out the concrete that react with other components of the concrete. Common materials are colliery shale, ash or even plaster. Often these materials are solid and do not react unless the damp-proof membrane has perforated. Moisture will be the catalyst that enables the chemical reaction to occur.

The repair of a defective floor is often its removal and the building of a new floor. The cost is almost as significant as the disruption caused by the repair. If you were buying a house that is potentially at risk we would strongly recommend that the floor be tested before you commit yourself to the purchase.

Damp in concrete can cause deterioration in the building materials as highlighted above. In addition it will also put adjoining timbers at risk from rot and woodworm. Dampness will also cause the deterioration of carpets and other floor coverings. If damp is occurring, timber and damp-proofing reports should be obtained. If you are about to buy a home with this defect, all costs of repair should be obtained to establish if the purchase price needs to be renegotiated to reflect this, or indeed to establish if you want to proceed.

Suspended Concrete

New house builders are using suspended concrete floors more frequently as many of the component parts can be pre formed in a factory and simply assembled on site. Floors of this type are durable, less susceptible to damp and relatively warm, reducing draughts.


Floating floors are a hybrid construction type and involve a floor (usually timber) being built on polystyrene blocks or wooden joists over a concrete floor. Floors of this type are warm, quiet and allow services to be easily incorporated underneath.

Many of the defects to floors are caused by either damp penetration or rising damp. If you are aware of a damp problem you should repair the defect as soon as possible as the cost of repairs at a later date could be much greater. If dry rot occurs it spreads very rapidly as does the cost of repair. Early repair is therefore vital.