How to renovate metal roofs.

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The Problem

Metal roofs are used all over the world to cover warehouses, factories,  farm buildings, houses and many other types of buildings. They are subjected to extreme conditions and stresses due to their constant exposure to pollution and  aggressive weather.

Sheets expand and contract continuously under the influence of changing temperatures. At the same time, they need to protect against corrosion and degradation from continuous exposure to the elements. Climates around the world are becoming more extreme with increased rainfall and above average temperatures.

Most roofs are coil coated steel or galvanized steel. Produced on coil coating plants and supplied to specialist metal cladding and roof fabricators who cut, fabricate, and insulate sheets for delivery to site. The most common coatings applied at the coil coaters are plastisol, pvdf and polyester powder coating. Although some galvanised steel roofs are left uncoated and painted later on site.

 

The quality of these coatings may vary, but they will all eventually degrade leading to cracking, detachment, corrosion, metal loss and ultimately leaks. Once this process commences it is critical to act fast to protect the structure and contents of the building. The economic losses are high in terms of asset write off and lost production.

Elastometal is an easy to apply and a cost-effective solution. An Anticorrosion Waterproof Elastomeric coating which will considerably extend the life of your metal roof and building.

Rusty Roof
The Solution

Elastometal

15 Years service life in C5-M  Marine environments.

Elastometal is a unique single product solution for renovating metal roofs, an anticorrosion waterproof elastomeric coating available in an extensive range of RAL Classic and NCS colours. It has a service life in excess of 15 years in the most aggressive C4 industrial and C5-M marine environments.

Elastometal is a high performance ecological and sustainable coating with excellent adhesion and flexibility. With 200% elasticity it has the flexibility to withstand expansion and contraction of metal roof panels without cracking or detachment. Applied direct to metal it is a single product solution for renovating metal roofs, with excellent adhesion to plastisol, pvdf and polyester powder coated sheets. A low odour, low emission ecological and sustainable coating available in an extensive range of colours in a matt 15% finish. Made in the West Midlands for free delivery throughout the UK.

Coverage Rates.

The thickness to be applied will depend on the slope of the roof and the environment. On a roof with a slope of at least 4%, a total dry film thickness of 350 microns (14 mils)  is recommended , with a total coverage rate of 0.8kg per square metre. Two coats will be required by airless spray to achieve this dry film thickness.

Benefits & Performance

Elastometal has a life expectancy in excess of 15 years. The system has a global track record Waterproofing, Protecting and Decorating metal roofs and cladding. It delivers great benefits to the owner of the building in terms of a cost-effective solution without the need for abrasive blast cleaning. An economic alternative to Noxyde it is available in an extensive range of RAL and NCS colours with free next day delivery. For the applicator it is a simple safe single product solution which is easy to apply.

For the project manager:

  1. Economical solution for metal roofs.
  2. Highly effective and durable system.
  3. 15 Year performance.
  4. Ecological and sustainable paint.
  5. Low VOCs and Emissions. No fire risks.
  6. Low Odour, minimal disruption.
  7. Made in the West Midlands.
  8. Wide choice of RAL & NCS colours.
  9. Free Next Day Delivery no hidden costs

For the applicator:

  1. .Single product solution. No primers
  2. Safe and Easy to apply. No fire risk.
  3. Low Odour Low Emissions.
  4. Fast drying and overcoating.
  5. High solids high build coating.
  6. Dry fall coating, less maintenance.
  7. Made in the West Midlands.
  8. Wide choice of colours.
  9. Free Delivery to site.
Preparation

Weather

As with any outdoor project, try to avoid starting a job in wet conditions. A minimum of 10°c (50°f) and no rain forecast during and immediately after application are required to be able to apply the product successfully. Above 15°c (59°f) working conditions are perfect and enable higher productivity. If the project is located in a very hot area with very intense sunshine avoid applying the system when the sun is the most intense and  work early in the morning or in the late afternoon.

If you are working in humid climates, and especially if it is cold after sunset such as in the autumn, be sure to complete the job a few hours before dark. To avoid the risk of condensation lying on the fresh paint and preventing it from drying. If you are working at dawn, be mindful of condensation on the surface.

Surface preparation

The surface must always be clean, dry, degreased, and free of any contaminant.

Eco Powerclean  a powerful biodegradable alkaline concentrate composed of anti flash rust additives for cleaning and preparing surfaces is recommended before painting. When high pressure water blasting up to 4% Eco Powerclean can be added to clean water to improve degreasing and temporarily protect the surface from flash rusting. After application the surface should be left for 2 to 3 minutes for it to react with the metal. It will significantly improve the corrosion protection on exposed metal surfaces and reduce cleaning times. At 5% dilution usage is 100m2 per litre. Allow to dry before applying Elastometal.

High pressure water blasting is recommended at a minimum of 180 bar / 2600 psi equipped with a rotating zero-degree angle nozzle. This method will remove surface contaminants, loosely adhering paint and rust.

 

 

Cleaning by mechanical or power tools is  advised when more detailed surface preparation needs to be done, on objects within the roof, such as chimneys, access ladders and bolts that could be heavily rusted.

Moss and mould can be removed with Eco Powerclean biodegradable solution.

Inspect and Treat Bolts

It is important to inspect the condition of the bolts securing the metal panels to each other and to the roof structure. Defective fasteners and bolts must be repaired or replaced. Brush on a coat of Elastometal on each fastener after inspection. This will help visualize the progress of the inspection, and add a protective first layer on vulnerable areas.

Edges and ridges

Check the edges and ridges of roofs and sheets as these areas are  susceptible to corrosion. Remove all contaminants and apply a stripe coat of Elastometal by brush for additional protection.

Non Ferrous metals and smooth surfaces

Degrease and lightly abrade all non-ferrous metals such as aluminum, galvanized and stainless steel. Monoguard can be used as a primer on new galvanized and stainless steel.

Equipment

Elastometal can be applied by brush on specific localised areas and with by airless spray on the main surface. If spraying is not practical, it can be applied by roller although you will need to apply more coats to achieve the minimum thickness required.

For airless spray use a pressure of at least 180 bar or 2600 psi and a spray tip between 0.017 and 0.023 inches.

For application by roller, it is recommended to use 14 mm / ½ inch polyamide rollers.

System Application

Protection of intersections between metal panels

If leaks are occurring due to metal loss, overlapping joints or at joints around roof stacks, a roof fleece should be applied for additional reinforcement and protection.
Use the 20cm (8inches) wide  roof fleece  and cut it to the appropriate length. The fleece is perforated and extremely tough virtually impossible to tear.

Lay the fleece evenly over the intersections and brush a coat of Elastometal through. Repeat this operation at all intersections.
Other areas may also require the use of the fleece:

  • very rusty areas with potential metal loss
  • near chimneys and exhausts where there could be aggressive or polluting fumes
  • areas where water could pond and stagnate
  • connections with walls or other elements present on or along the roof.

Allow the Elastometal to dry for 4 hours at 15c, before recoating. Drying times will be longer below these temperatures.

Mixing

Elastometal is supplied ready to use, stir it mechanically for several minutes.

In very hot weather, up to 3% clean water can be added to reduce the drying time. Do not exceed 3% water as this will affect the anticorrosion properties.

The application

Application by airless spray is recommended as fewer coats will be required. Two full coats are recommended to a total dry film thickness of 350 microns. Apply Elastometal over the entire surface following the slope of the roof. In windy conditions try to work so that potential overspray does not create dry spray. Allow  4 hours between coats.

Apply the second full coat of Elastometal over the entire surface in the same manner as the first.

Since you will be walking on a soft, elastomeric and freshly painted surface, consider wearing shoes with smooth soles.

Application by roller may require additional coats to achieve the recommended dry film thickness. Approximately 0.8kg per square metre should be applied in total for optimum performance.

Advice

If you have had to interrupt the application for a few days, make sure that the surface is not contaminated with dirt or any other type of pollution when restarting. If so, rinse the surface with a pressure washer.

If possible, choose different colours for each layer to act as a visual aid ensuring two coats are applied in all areas. Elastometal has very good opacity.

Details such as metallic objects, corners and edges are usually applied with a roller or brush for greater accuracy.

Consider measuring the thickness of your wet film using a comb gauge before it dries to help you determine your dry film thickness. An electronic metal gauge can be used to measure the final dry film thickness applied.

The final thickness is important and must comply with our recommendations.

Congratulations your  metal roof is now protected against water infiltration and corrosion.

Roof Spraying