The interior design guide
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The interior design guide. A definitive knowledge base for interior designers.

From first principles to the finishing touches: shell, surfaces, space planning, furniture, electrics, plumbing and joinery, in the order a project runs.

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The Lexicon.

Every term, in plain words.

From hue and light reflectance to bonding and kick space, every term the guide uses has a short definition, what to know in practice and the pages that use it.

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The interior design guide.

A definitive knowledge base for interior designers.

Eleven chapters take a home from first principles to the moment you show it to the client. Start with Foundations and read in order, or search for a topic, a term or a rule of thumb.

Chapters.

Eleven steps, from principles to presentation.

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Where to go next.

Sections.

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Where to go next.

Shelf span.

What it means in interior design.

Shelf span is the unsupported length of a shelf between its supports. Longer spans and heavier loads make shelves sag over time.

In practice

For full bookshelves in 18 mm board, keep spans to about 70–80 cm; thicker or solid timber shelves go further (rule of thumb). A front lip or a hidden steel flat stiffens longer runs.

Where the guide uses it

  • Defined here, in the Lexicon.

Related terms.

More from Joinery & millwork.

Back to the Lexicon

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