Fixings & Fasteners Calculator
Estimate screws, plugs or repeated fixing quantities, spare allowance, pack counts and optional cost.
Typical use: Screws, wall plugs and repeat fixings for non-structural DIY quantity planning
Using this calculator
Open the interactive calculator to enter your project measurements and adjust the available settings. Review the calculated quantity and buying units before ordering materials. Check product coverage, pack sizes and installation guidance with the manufacturer or supplier.
Planning and practical guidance
How to Hang a Shelf Safely: Walls, Fixings & Hidden Services
Choose shelf positions and wall fixings sensibly, check for hidden services and understand why the shelf load and wall construction determine the fixing method.
- Choose the shelf position and think about the real load it will carry, including heavy books, kitchenware or objects that may be added later rather than just the empty shelf.
- Identify the wall construction as accurately as possible. Solid masonry, timber studs, dot-and-dab plasterboard and hollow stud walls need different fixing strategies.
- Check for likely cable and pipe routes before drilling. Electrical cables are commonly routed vertically or horizontally from switches and sockets, but a detector and sensible caution are still needed.
- Mark bracket positions with a level and make sure the bracket spacing is suitable for the shelf material and expected load so the shelf does not sag between supports.
Wall Plugs & Fixings Explained: Match the Fixing to the Wall
Understand why solid masonry, hollow block, plasterboard and cavity walls need different fixing approaches.
- Identify the substrate before selecting the fixing. The visible plaster/paint layer does not tell you whether the structure behind is solid masonry, hollow block, plasterboard or timber stud.
- Use a fixing whose manufacturer explicitly lists the substrate and load/application you intend to use.
- Match the drill diameter to the fixing manufacturer’s specification and drill a clean hole to the stated depth.
- Remove drilling dust where the fixing instructions require it; dust can stop plugs seating correctly and can affect higher-performance fixings.