- Do you need to remove the plastic strip on the BARDOLINE shingle strip?
- How thick should the roof deck be?
- Can you drill a hole in the sheets to install a flue?
- What are the White marks on the under side of the Onduline sheet?
- Can you install Onduline sheets on a Pent Shed?
- Can you replace Asbestos sheets with Onduline?
- Can you lay Onduline on top of Asbestos?
- Do Onduline sheets contain asbestos?
- Do you supply Onduline in different lengths?
- What is the difference between Onduline and Coroline?
- Does the onduline material melt in hot weather?
- How long are Onduvilla tiles guaranteed for?
- Are Onduvilla tiles fire resistant?
- What are Onduvilla tiles made from?
- Can I use Onduline bitumen sheets for cladding?
- What is the size of ONDUVILLA tiles?
- What is the role of the embossed lines?
- Do you supply Onduvilla tiles in different lengths?
- What is ONDULINE® Sealsmart technology?
- What is the size of an Onduvilla ridge?
- About the importance of bitumen content and HOMOGENEOUS IMPREGNATION.
- How long does the ONDULINE guarantee last?
- Can you stand on the classic sheets if the roof under them is solid?
- ONDULINE® sheets are in compliance with European Norm EN 534:2010+A
- Is Onduline Fire Resistant?
- When should I use ONDUTISS AIR Membranes?
- What colours are ONDUVILLA tiles available in?
- Do you sell clear PVC sheets to match Onduline profile?
- Are Onduline's sheets the same as Asbestos sheets?
- What is the overhang needed for Onduline sheets?
- What is the minimum pitch for Onduline sheets?
The white raid on the bottom surface of the sheets results from the standard manufacturing process of our products and is a very rare but completely natural occurrence. It comes from agents used during the manufacturing process. The dose of these agents depends on the characteristics of the raw materials used. Therefore, it may appear on sheets from one production batch, and on the overwhelming majority of others, it will not appear at all.
The main component of the raid (approx. 90%) is calcium lactate hydrate. It is a water-soluble compound, hence it has the ability to reach the surface and crystallize on the sheet. This compound is not classified as dangerous. In the food industry it is used as a preservative under the symbol E327, it works mainly against fungi and yeasts.
The white raid is not a factory defect, but is only aesthetic. It occurs when the sheets are new and wears off after a few months of use. It in no way affects the waterproofing of the cover and the performance of the product, which we guarantee as a manufacturer. The sheets are a full-value product.
The white raid will go away on its own with time. However, if you want a quick effect, it is enough to wash the sheets with water and ordinary dishwashing liquid (without vinegar), using a sponge, a soft cloth or a brush.
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