Flat roofs have become a popular option in the construction industry due to their sleek and modern look. However, to ensure that your flat roof is structurally sound, you need to consider the spacing of the components used in the construction process. In this article, we’ll explore what the spacing for flat roofs is and why it is important.
What Is The Spacing For Flat Roofs?
The spacing for flat roofs varies depending on the type of components used in the construction process. Generally, the joists will be placed at 400mm centres. This spacing ensures that the flat roof can support the weight of the components used in the construction process.
For spans up to 75 feet, the most economical spacing will be from 12 to 16 feet. This spacing is ideal for buildings with large flat roofs such as warehouses, factories, and commercial buildings. It ensures that the flat roof can support the weight of the roof deck, insulation, and any other components used in the construction process.
If the rafters of a flat roof need to span 18 feet, the spacing will be slightly different. The rafters will need to be placed at 600mm centres to ensure that the roof can support the weight of the components used in the construction process.
Do Flat Roofs Need An Air Gap?
Yes, flat roofs need an air gap. A ventilation gap of at least 50mm must be in place between the insulation and the underside of the flat roof deck. This gap allows air to circulate, preventing condensation from forming on the underside of the roof deck.
Without an air gap, moisture can build up on the underside of the roof deck. This moisture can lead to the growth of mold and other fungi, which can cause health problems. Additionally, moisture can damage the insulation, reducing its effectiveness.
How Is The Spacing For Flat Roofs Determined?
The spacing for flat roofs is determined by several factors, including the type of components used in the construction process, the span of the roof, and the weight of the components used in the construction process.
When determining the spacing for flat roofs, it is important to consider the load capacity of the components used in the construction process. The load capacity will determine how much weight the flat roof can support. If the load capacity is exceeded, the flat roof can become structurally unsound, leading to potential collapse.
The span of the roof also plays a role in determining the spacing for flat roofs. The longer the span, the more support the flat roof will need. As previously mentioned, if the rafters of a flat roof need to span 18 feet, they will need to be placed at 600mm centres to ensure that the roof can support the weight of the components used in the construction process.
Finally, the weight of the components used in the construction process will also determine the spacing for flat roofs. If heavier components are used, such as large air conditioning units, the spacing will need to be closer to ensure that the flat roof can support the extra weight.
