As you may know, roofing sheets are subject to thermal expansion and contraction due to temperature changes. When the weather changes, expansion and contraction start lengthwise from the center of the sheet and move outwards. This results in maximum expansion and contraction at the ends of the sheet: meaning that the maximum length between the top and bottom rows for screw-fix decks should be at most 24m for roofs. It is crucial to be aware of the number because if the length exceeds 24m, the thermal expansion and contraction can elongate screw holes, rendering the washers ineffective and resulting in damage to the structure and, of course, costly repairs.
This article discusses how thermal expansion can adversely affect your roofing structure and what are the ways to prevent it:
It is common for roofs of all materials to expand and contract due to the impact of climatic changes. However, people with metal roofs have to deal with noise due to thermal expansion because metal is a highly conductive material, and its atoms rapidly move and expand when they are heated. This expansion can cause the metal sheets to rub against each other, causing a loud noise. Similarly, metal roofs can also contract and move during cold temperatures, producing noise. The noise can be especially noticeable in buildings with large roofs or open spaces where the sound can echo and reverberate. However, proper installation techniques and appropriate fasteners and insulation can help minimize the noise.
This expansion and contraction can also cause strain, damaging the building. When materials are excessively restrained and cannot expand, the built-up internal stress is released, resulting in cracking, buckling, bowing, and other forms of deformation.
While thermal expansion and contraction is a natural process that cannot be prevented, you can take utmost precautions to minimize the impact by using the best quality self-drilling screws with EPDM washers. Here’s how: