Bookcases & Shelving Units Sizes Explained

In depth

Understanding the terminology surrounding bookcase and shelving unit sizes can feel surprisingly complex. It’s not simply about choosing a ‘small’, ‘medium’, or ‘large’ option – manufacturers use a system based on internal width, which is often misleading for consumers. The most crucial measurement is the 'internal width', representing the space available *within* the shelves themselves. This isn't the external dimensions of the unit; it's the space where your books and belongings will actually reside. Manufacturers typically quote this in centimetres, and it’s vital to understand that a bookcase labelled ‘120cm wide’ will only hold items up to 120cm deep – perhaps less if you factor in the thickness of the shelf itself. Pay close attention to whether the quoted width includes or excludes the sides of the unit; some manufacturers include the side panels, inflating the measurement, while others don't.

The most common sizing system within the UK market is based on multiples of 60cm. You’ll frequently see units described as ‘60cm wide’, ‘90cm wide’, ‘120cm wide’, ‘150cm wide’, and so on. This isn’t arbitrary; it reflects a standard approach to shelving design, primarily developed for European furniture manufacturing. A 60cm internal width is generally considered suitable for smaller books or magazines, while a 90cm width can accommodate larger hardbacks. The jump to 120cm is more substantial and often intended for dedicated bookshelves housing a significant collection of books. Larger units, like 180cm or 240cm, are typically reserved for extensive libraries or dedicated display areas. When considering these wider units, you'll often find that the overall external dimensions are significantly larger to accommodate the structural support needed for greater spans. Don’t be misled by the large external size; it’s the internal width that dictates what you can store comfortably.

When assessing a space for a bookcase or shelving unit, begin with accurate measurements – and don't just consider wall length. The depth of the unit is equally important. A shallow unit (around 30-45cm deep) might be ideal for a narrow hallway or alcove, while a deeper unit (60cm or more) allows you to stack books and items without them protruding excessively into the room. Also, factor in the height – taller units require higher ceilings, and shorter units may look awkward if they’re too low to the ground. Remember that furniture retailers often round measurements up for marketing purposes, so always double-check the manufacturer's specifications before making a purchase.

A common mistake among UK shoppers is focusing solely on the external dimensions of the bookcase when measuring their space. This leads to frustration and disappointment when the unit doesn’t fit correctly. As previously mentioned, manufacturers frequently include the side panels in the quoted width, which can easily add 10-20cm to the measurement, creating a false impression. Always prioritize the internal width – it's the crucial number for determining what you can store. Moreover, consider the overall footprint of the unit; a wide bookcase will dominate a room, while a narrow one might get lost in the background.

Consider the intended use of the shelving when selecting a size. A home office demands a more substantial bookshelf than a small hallway display case. If you plan to store large volumes of books, prioritise internal width and depth over minimising the overall footprint. Conversely, if space is at a premium, you might opt for a shallower unit with a narrower internal width, sacrificing some storage capacity for greater flexibility. Think about what items you'll be storing – are they primarily books, or do you need to accommodate decorative objects, photographs, or other personal belongings? This will influence the necessary depth and overall size of the shelving unit.

Finally, remember that furniture sizes can vary slightly between manufacturers, even within the same product range. Always scrutinise the specifications carefully before purchasing and read customer reviews to get an idea of the actual dimensions experienced by others. Don’t hesitate to contact the retailer directly if you have any doubts or require clarification on the internal width measurement – it's far better to ask questions upfront than to end up with a bookcase that’s too small for your needs. Accurate measurements and careful consideration of your space are key to selecting the perfect bookcase or shelving unit to suit your home and your belongings.