How much does it cost to refurbish a balcony?
Balcony refurbishment costs vary according to the balcony’s size, construction and condition, the scope of the work and the products specified. As a broad guide, replacing a loose-laid floor covering on a sound, load-bearing substrate often costs around €50 to €100 (£45 to £85) per m². If new waterproofing and associated junction details are required, costs are more likely to be around €150 to €400 (£130 to £350) per m². Full refurbishment involving concrete repairs and a completely new build-up can cost €1,000 (£850) per m² or more.
Depending on the condition of the balcony, refurbishment may include the following stages:
• Removing the existing floor covering and disposing of it
• Exposing and assessing the load-bearing structure
• Repairing damaged concrete and corroded reinforcement
• Forming or correcting a fall of around 2%
• Installing waterproofing with properly detailed door and wall junctions
• Addressing thermal bridging at a cantilevered slab where required
• Replacing the balustrade to provide compliant guarding
• Laying a new floor covering
• Finishing or cladding the walls
Significant additional costs may become apparent only after the existing covering has been removed. On cantilevered reinforced concrete slabs, water can penetrate through cracks and defective junctions. Carbonation and freeze-thaw cycles can then lead to reinforcement corrosion and concrete spalling. Corroded reinforcement must be cleaned and passivated, and the concrete must be reprofiled before waterproofing is applied. Cracks, reinforcement damage or a proposed increase in build-up height should be assessed by a specialist contractor or structural engineer.
Effective drainage depends on a properly formed fall, suitable outlets and adequate junction heights. In accordance with accepted good building practice, the waterproofing should bridge cracks and be turned up at door thresholds and adjoining walls. The need for insulation depends on how the balcony is connected to the building. Self-supporting timber or metal balconies carried on their own posts are thermally separate and do not require insulation at the junction. A continuous concrete slab forms a thermal bridge and can generally be fully separated only as part of more extensive alteration work.
The choice of floor covering also affects installation and maintenance costs. Ceramic tiles may spall after freeze-thaw exposure, timber needs regular maintenance and can rot, and WPC can become hot and may distort. A weather-resistant alternative is WARCO rubber tiles made from PU-bound rubber granules. They are free-draining and can be laid without adhesive on a suitably prepared balcony substrate.
The overall calculation should include purchase and installation, disposal, any concrete repairs and the expected costs of subsequent care and maintenance.