The interior design guide
Open Rayon

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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Use the guide in your AI assistant.

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The guide has an MCP server, so your assistant can search it, read its pages and cite them while it answers you. It is free, read-only, and needs no account or key.

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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.

Plumbing.

Where does water come in, and where does it leave?

Water decides more of a plan than most designers expect: the soil stack fixes where the bathroom can go, and every tap needs supply in and waste out with enough fall. This chapter covers supply, waste, heating and the rooms that depend on them.

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Sections.

Everything about plumbing.

Planned

Where the soil stack sets the plan

Why the soil stack decides where bathrooms and kitchens can go.

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Planned

Supply, waste and fall

How water arrives and leaves, and the falls waste pipes need.

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Planned

Kitchen sink and appliances

Placing the sink, dishwasher and washing machine around the pipes.

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Planned

Bathroom layout around the WC

Planning a bathroom from the WC and its connection outwards.

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Planned

Showers: valves, trays and wet rooms

Choosing between trays and wet rooms, and placing the valves.

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Planned

Heating: radiators or underfloor

Comparing radiators and underfloor heating room by room.

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Keep reading.

Where to go next.

Units