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Ball Park Demo

Ball Park Demo

How To Guide:

This calculator is designed for the general homeowners across the UK wanting to understand the cost of how much their new extension will be? Perhaps a double storey extension? Thinking about whether you are going to be building it with brick or maybe render? Please see below a step-by-step guide on how to use the calculator. We also have a video that will guide you through the process.

  1. Choose your style of build. Are you wanting to know the cost of a single or double storey extension or a new build.

  2. Now the duration of this build. This will help calculate your site overhead costs.

  3. Click for adding preliminaries to the calculator. A description of what preliminaries are is stated under this option.

  4. Does your build require foundations? This will only be mandatory if it’s a ground floor extension and not being built of an existing structure.

  5. If this option is required, please give the overall length of foundations needed. For example, if your extension is 3 meters out from your existing building and 8 meters long this would 3+3+8, making 14 meters in total. This will also determine the volume of the walls for ground floor presumed at 2.4m high for a ballpark.

  6. This option is only need for first floor extension. If this option is required, please give the overall length of walls needed. For example, if the length of the first-floor walls are 3m out from your existing building and 8 meters long this would 3+3+8, making 14 meters in total. This will also determine the volume of the walls for ground floor presumed at 2.4m high for a ballpark. Please note that if you have chosen a double storey extension then you are to answer point 4 and 5.

  7. This option is for a drainage package allowance, it includes pipework, manhole and a soakaway for ballpark purposes.

  8. If you are building from the ground up you will require a concrete slab, so please select this option. If you are planning on building a first-floor extension this option is not required.

  9. Please enter the size of your ground floor area for the calculator to be able to work out the costs. Using the example above- if your extension is 3 meters out and 8 meters long then you multiply the width by length. (3x8 = 24m2). This is only required if building from the ground up.

  10. If you are building a first-floor this option is required.

  11. Please enter the size of your first-floor area for the calculator to be able to work out the costs. Using the example above- if your extension is 3 meters out and 8 meters long then you multiply the width by length. (3x8 = 24m2). This is only required if you are building a first-floor extension.

  12. Now onto the wall finishes. Please choose from the two most commonly installed wall finishes in the UK, brick or render. This will calculate the two skins of masonry, wall finish, wall ties, damp courses and insulation. If you require more options, please purchase our Estimator Pro calculator.

  13. Is your roof a flat roof or pitched roof? All you need to do is choose the style, we have taken enough information to calculate the costs for you.

  14. Inside your extension, do you require any additional walls? Perhaps you are wanting to create another room? Select this option if required.

  15. Please enter the over length of the wall and our calculator will calculate all the carpentry, insulation, drylining to these walls. The calculator has allowed for 2.4m high walls for the purpose of the ballpark.

  16. Are you wanting to know the costs of plastering? Click this option to get a cost to plaster all walls and ceilings.

  17. Select this option if internal doors are required.

  18. Choose the number of internal doors that are installing into the project.

  19. What style of external doors would you like? The choice is yours?

  20. Select if windows are required.

  21. How many are required. Window are set at 1.2 x 1.2m for ballpark.

  22. Do you require a roof lantern size is set at 2m x 1m for ballpark

  23. Select if veluxes are required.

  24. How many are required.

  25. Are you having a kitchen in your extension. Choose from the three options. If no kitchen is required please move on to the next option.

  26. If your projects needs plumbing, please choose from the following options that you need plumbing for.

  27. Same applies for the electrics.

  28. Do you want the decoration included? If you choose this option our calculator will work out all the decorating costs to apply white paint to all new areas of ceilings, walls and woodwork.

  29. Click this option if you require scaffolding.

  30. Click this option if you require skips.

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