Calculating the shuttering quantity for a staircase involves determining the total surface area of the formwork (shuttering) required to construct the staircase. Formwork is the temporary structure used to support and shape the concrete during the casting process. Here’s a step-by-step guide to help you calculate the shuttering quantity for a staircase:
Step 1: Identify the Components of the Staircase
Break down the staircase into its individual components, such as the treads, risers, landing, and any support beams or walls associated with the staircase.
Step 2: Measure the Dimensions
Measure the dimensions of each component, including the length, width, and height. For treads and landings, measure the length and width. For risers, measure the height and width. If there are any support beams or walls, measure their dimensions as well.
Step 3: Calculate the Surface Area of Each Component
Calculate the surface area of each component using the appropriate formula based on its shape:
- For rectangular components (treads and landings): Surface Area = Length × Width
- For vertical components (risers, support beams, and walls): Surface Area = Height × Width
Step 4: Determine the Total Shuttering Quantity
Sum up the surface area of all the components to get the total shuttering quantity required for the staircase:
Total Shuttering Quantity = Sum of Surface Area of All Components
Step 5: Account for Reusability
If the formwork is reusable (e.g., plywood formwork), you can adjust the shuttering quantity by considering the number of times each component will be used for multiple casting cycles.
Step 6: Add a Safety Margin
To account for potential wastage and unforeseen circumstances, add a safety margin to the calculated shuttering quantity (usually around 10% to 15%).
Let’s assume we have a staircase with the following dimensions:
- Tread (Length × Width): 1.2m × 0.3m
- Riser (Height × Width): 0.15m × 0.3m
- Landing (Length × Width): 1.2m × 1.2m
- Surface Area of Tread = 1.2m × 0.3m = 0.36m²
- Surface Area of Riser = 0.15m × 0.3m = 0.045m²
- Surface Area of Landing = 1.2m × 1.2m = 1.44m²
Total Shuttering Quantity = 0.36m² (Tread) + 0.045m² (Riser) + 1.44m² (Landing) = 1.845m²
Adding Safety Margin (10%): Total Shuttering Quantity = 1.845m² + 0.1845m² = 2.0295m²
By accurately measuring and calculating the surface area of each component of the staircase, you can determine the total shuttering quantity required for the construction process. Adding a safety margin accounts for any unforeseen variations or wastage, ensuring you have sufficient formwork for the entire project.