How to measure a bookshelf
Measure a bookshelf by first determining its purpose. Record the internal width, height, and depth of each shelf, considering obstructions like decorative molding. Measure the overall external dimensions for placement or moving. Use a tape measure and account for slight variations. Always double-check your readings for accuracy.
Measuring a bookshelf accurately is essential, whether you’re buying a new one, assessing your current collection’s needs, or planning to move. The process involves taking both internal and external measurements, depending on what you need the dimensions for. You’ll need a reliable tape measure. A metal tape measure is generally preferred for its rigidity and accuracy, especially for longer spans. Before you start, decide if you’re measuring for specific book heights, decorative items, or the overall footprint of the unit.
For most practical purposes, you’ll want to know the usable space within the bookshelf. This means measuring the interior dimensions of each shelf. Start with the **internal width**. This is the distance between the two vertical side panels of a specific shelf. Extend the tape measure from the inside surface of one side panel to the inside surface of the other. Ensure the tape is held straight and level. Note this measurement down for each shelf, as they can sometimes vary slightly.
Measure the internal height of each shelf
Next, measure the **internal height** of each shelf. This is the vertical distance from the top surface of the shelf below (or the bottom of the shelf itself) to the underside of the shelf above (or the top of the shelf itself). Again, keep the tape measure straight and level. This is critical for ensuring your books or decorative items will fit comfortably without hitting the shelf above. If you have adjustable shelves, measure the space available between the shelf supports for each potential position, or measure the fully extended space.
Measure the internal depth of each shelf
The **internal depth** is the distance from the front edge of the shelf to the back panel or wall of the bookshelf. Extend your tape measure from the frontmost interior surface to the rearmost interior surface. Be aware of any obstructions at the back, such as mounting hardware or decorative elements, that might reduce the usable depth. For books, especially larger ones, ensure the depth is sufficient to support them fully without overhang.
Measure the overall external dimensions
If you’re determining where a bookshelf will fit in a room, or if you need to transport it, you’ll need the **overall external dimensions**. This includes the total width, height, and depth of the entire unit. Measure the widest point for the width, the highest point for the height, and the furthest point from the wall for the depth. Pay attention to any protrusions, such as decorative trim, baseboards, or legs, as these can affect how the bookshelf fits in a specific space or passes through doorways.
Account for obstructions and variations
When measuring, always be mindful of any decorative elements or structural features that might impede placement or storage. This includes moldings around the edges, built-in supports for adjustable shelves, or the thickness of the back panel. If the bookshelf is built into a wall unit, you might need to measure around these architectural features. Even seemingly minor details, like a slightly curved front edge or a thicker back panel, can affect your final measurements. Always double-check your readings, especially if you’re ordering a custom-built shelf or planning a tight fit.
Tools for measuring
The primary tool you’ll need is a **tape measure**. A 12-foot or 25-foot metal tape measure is ideal. For very large units, a longer tape might be necessary. A **pencil and paper** or a smartphone with a notes app are essential for recording your measurements. It’s helpful to sketch a simple diagram of the bookshelf and label each dimension as you record it. This visual aid can prevent confusion later on. If you’re measuring for a specific fit in a recessed area or against a wall, a **small ruler or folding ruler** can be useful for tight spots, though a tape measure is usually sufficient.
Common Mistakes When Measuring a Bookshelf
| Step/Tool | Typical Mistake |
|---|---|
| Measuring Internal Width | Forgetting to measure between the inside surfaces of the side panels, or not accounting for shelf support pegs that reduce usable width. |
| Measuring Internal Height | Not accounting for the thickness of the shelf above or below, or measuring to the outside of decorative molding. |
| Measuring Internal Depth | Ignoring obstructions at the back of the shelf like paneling or mounting hardware, leading to a smaller usable depth. |
| Using a flexible tape measure | A soft tape measure can sag or bend, leading to inaccurate readings, especially for longer shelf spans. |
FAQ
Do I need to measure the thickness of the shelves themselves?
You typically don’t need to measure the thickness of the shelves unless you’re concerned about the overall external dimensions or if the shelf material is unusually thick and might interfere with book placement at the very front or back.
How do I measure a bookshelf that is built into a wall?
For built-in bookshelves, measure the opening where the shelves are located. Record the interior width, height, and depth of each compartment. Also, measure the overall external dimensions of the built-in unit, noting any surrounding trim or molding that affects the fit.
What if the bookshelf is not perfectly square?
Measure at multiple points along the width, height, and depth, and record the smallest dimension. This ensures that your items will fit within the tightest part of the shelf space. For external measurements, measure the maximum extent of the unit.
How much clearance should I leave around a bookshelf?
For basic placement, leave enough space for the bookshelf to be maneuvered into position and for you to access items. If it’s a freestanding unit, consider the depth of the unit plus a few inches for airflow and cleaning. For built-ins, ensure minimal gaps, typically just enough for paint or minor settling.