At some stage, the metal cladding on your building will start to deteriorate and require refurbishment. The majority of metal roofing and cladding sheets are produced from steel and zinc-alloy coated, before being finished with a factory-applied protective coating. It is the finishing layer of coating that usually needs replacing; however, to simply over-sheet the existing metal presents a number of, often hidden, disadvantages.
The primary question, first and foremost, is to ask whether your building structure can take the weight of over-cladding. An additional layer of the recommended gauge steel sheets and supports is a heavy load to bear, notwithstanding the need to calculate the weight of any snow loading into the over-sheet layer.
Furthermore, choosing to over-clad would involve the use of ‘through fix’ installations, utilising the existing purlins: meaning it would be necessary to drill additional holes into the existing sheet. With more holes in the building roof and wall covering, you risk air leakage and increased moisture penetrating the sheeting: causing problems with condensation.
Condensation in itself presents additional problems if you simply choose over-cladding, rather than refurbish, your building’s metal cladding. If you retain the old roof as a liner, and it cannot be sealed, you will need to add a new vapour protection layer. This VPL ought to be located above what will now become your internal sheet, and you will need to puncture it with fixings for the new skin’s support bracket. However, this makes the layer extremely difficult to seal and, with the additional fixings, you are risking ‘cold bridging’.
In addition, over-cladding makes it essential that you consider the performance of other, existing, materials. A huge variety of sealants, thermal performance materials, and support and ancillary fixings must now match the design life guarantee of the over-sheeting system you have used, adding additional expenses and complications that refurbishment through Cladding Coatings can prevent.
What’s more, over-cladding would present clear disruption to your site: increased storage requirements; large and heavy deliveries; storage; handling, and movement of men and materials, all needing to be carefully planned and safely managed through a strictly-controlled programme. In contrast, at Cladding Coatings, a dedicated Project Manager supports you from start to finish, and we focus on minimal disruption during operations: avoiding heavy disturbance at your site. Cladding Coatings can work evenings and weekends, around your operational hours allowing you to carry on as normal.
If the physical disadvantages weren’t enough, choosing to over-clad presents some real environmental concerns. Over-sheeting would mean double roof or wall sheet disposal at the end of the building’s life: presenting twice the cost, and doubling the environmental impact. What’s more, large resources of finite raw materials and non-renewable energy are required to produce steel sheets, raising questions regarding sustainability. If you have a steel roof already in place, recoating is all that is needed to protect it indefinitely.
In addition, just like the original sheet, the over-cladding itself will require recoating in line with repainting expectations. The existing performance factors you faced with the original layer will still be present with the new over-sheet: for example, it is almost inevitable that cut-edge corrosion will occur during the over-cladding’s lifetime. Therefore, choosing to over clad requires you to factor in a significant degree of future maintenance.
In summary, over-cladding can be a costly process that is damaging to the environment, and presents the risk of a number of future problems. If you chose to over-sheet, you are protecting the roof of your building with an unnecessary layer of steel; the over-sheet is heavy, the risk of condensation and leaks is high, and you must plan to repeat the works in the future: doubling the maintenance and lifestyle costs.
Enlisting the services of Cladding Coatings to repaint, rather than re-sheet, will maintain the strength and value of your building, prevent disturbance, and extend profiled metal sheet life indefinitely. In contrast to the problems encountered by over-coating, our environmentally-friendly refurbishment will add value, improve building appearance, and protect against corrosion and weathering.
With solutions including on-site spraying, painting and cladding coating, simply call our friendly and professional team on 0161 626 3493 to talk through your options and obtain a no-obligation quote: we’re always happy to offer our advice and expertise.