As a property investor you want to ensure that your investment will continue to hold its value by making the correct decisions when considering an external building makeover or repairs.
The exterior coating finish to your building should not only be pleasing to the eye but also a protection barrier to the elements. Weather, sun damage and pollutants affect the life span of exterior coating systems. Bodies corporate need to be more diligent when engaging a company to perform external building repairs and refurbishments to their investment. In major repairs it is recommended to engage an engineer to design a scope of works and make informed decisions regarding the products to be used for that particular project.
Reputable products on the market today have been designed to be applied at specific thicknesses to ensure elements such as salt cannot penetrate within the concrete pores and ultimately result in concrete cancer. As a large percentage of commercial holiday and residential buildings are situated close to the coast and its harsh environment, it is important to understand what protective coating systems are available.
Manufacturers today offer similar coating products with most guaranteeing long term durability. These include environmental impact, colour range, pollution, dirt and chemical attack qualities. Engineers prefer membrane style products as they provide all the required benefits. The best way to understand the difference between a membrane coating system and a paint application is that a membrane coating system protects the building façade and paint is essentially cosmetic.
Before any coating system is applied all remedial repairs should be carried out. Crack bridging is of high concern in new and old buildings, as foundations settle and cracks begin to appear allowing water and salt entry. Remedial works prior to coatings should treat the crack as per manufacturer’s guidelines. Fine, medium and large cracks all have certain preparation requirements and are treated as such.
Surface preparations are a vital component in the overall process and taking short cuts can be detrimental and in turn very expensive. All systems require the existing coating facade to be pressure cleaned to remove salts, debris and mould, and then treated accordingly. Priming of all surfaces, then application of two full top coats to achieve correct dry film thicknesses is essential for long term benefits. Manufacturers will not guarantee their products if the preparation and application guidelines are not met, thus voiding their manufacturer’s warranty.
To guarantee that that the manufacturer’s warranty is valid, it is highly recommended, that you appoint an independent third party to inspect and measure the application of products prior to completion of the works.
In addition to the building façade coating system, you need to consider if your building has a concrete roof, roof top usable areas, garden planter boxes or low lying areas holding water for long periods. These areas may have existing problem and the roof top membrane may have failed or been breached. The company you engage to repair external refurbishments will need to investigate and make allowances for remedial works to be carried out within the project.
Most manufacturers recommend the coating to be reapplied every seven to ten years. It is preferable to remove the original coating back to a sound substrate, apply external cementitious topping compounds and reapply new membrane system to manufacturer specification. Situations have arisen where the new coatings have been applied over the original coating and due to their age delaminate beneath the new coating and begin to blister. It is best trade practise to always remove existing coatings and start the new coating system on the original substrate. Most manufacturers are more comfortable with this method and warranties usually reflect this.
Another area for remedial maintenance is where building control joints or expansion joints are introduced where main construction joints are implemented for climatic changes. They are also created when large crack repairs or movement is occurring to reduce unsightly facade breaches and water entry points. Joint configuration is usually 1:1 width to depth or 2:1 for larger openings. Backing rod or tape is placed at the base and usually common polyurethane sealants are inserted until flush. The sealant can also be recessed to create an architectural feature which is usually preferred on exterior facades. MS polymer sealants are best used in these situations to stop pollutants from sticking to the coating system that becomes darkened.
To perform all these façade repairs and coating systems safe access is paramount. Every situation requires a different method or methods. Scaffold systems, cherry pickers, swinging stages, working platforms and abseilers are the common choices. Each method will need to comply with OH & S legislation. Each method should be inspected prior to works commencing.
Once your project is complete, it is imperative that ongoing maintenance is carried out as per the manufacturer’s requirements. If the manufacturer recommends that a building wash down should occur every two to three years, you need to allow for these works in your budget. If the recommended maintenance schedule is not adhered to, you could void the manufactures’ warranty and reduce the life expectancy of the product. This in turn costs more money to uphold the value of your investment.
Expert advice and a comprehensive scope of works should always be utilised when performing external building repairs. Bodies corporate have a duty of care when engaging engineers and reputable remedial companies to perform works. It is also recommended that when you are seeking prices to perform works that all tenderers are given the same scope of works and specifications in preparing for their company’s submitting their prices.
BOSS Building Remedial