How to Read an Assembly Instruction

Flat-pack assembly instructions look confusing, but they follow a consistent logic. How to read diagrams, symbols, and what order to work in.

Before You Start

  • Read the whole instruction once — without stopping to assemble anything. It takes 5–10 minutes and saves an hour of undoing
  • Count all parts against the list at the beginning — confirm nothing is missing
  • Sort the fixings by type: screws, cam bolts, dowels, confirmat screws — separate piles for each
  • Get your tools ready: what you need is listed on the first page of most instructions

The Parts List and Labels

At the start of the instruction there is a parts list: each part has a letter or number label, its dimensions, and quantity. This key applies to every diagram in the booklet.

  • Parts are labelled A, B, C or 1, 2, 3 — the same label is used consistently throughout all steps
  • Dimensions are in mm — double-check when you have several parts of the same type but different sizes
  • Fixings are listed separately, usually with a size code (M6×30 = M6 bolt, 30 mm long)
  • If a part label appears in multiple steps, it is used more than once — that is intentional

How to Read Assembly Diagrams

Most modern instructions are text-free: only pictures and arrows. The visual grammar is the same everywhere.

  • Arrow = direction of movement of a part or fixing
  • Dashed outline = a part already fitted in a previous step
  • Circle with a zoom = an important joint shown in detail
  • Number in a circle next to a fixing = how many of that fixing go in at this step
  • Cross or stop symbol = do not do this (usually shows incorrect part orientation)

Types of Fixing and How to Tell Them Apart

FixingWhat it looks likeWhat it does
Confirmat (euro screw)Thick screw with a hex headJoins two melamine board panels
Dowel (wooden peg)Round wooden cylinderAligns and positions parts
Cam lock (eccentric connector)Disc + bolt (minifix)Demountable panel joint
Wood screwThin, sharp-tipped screwAttaches hardware, back panels
Bolt and nutThrough-bolt + nutStructural load-bearing joints

How Not to Mix Up the Face and Back of a Panel

One of the most common assembly errors is fitting a panel the wrong way round. Instructions show this, but it is not always obvious.

  • The face side is the laminated surface — smooth, with the decorative finish
  • In diagrams: the face side is usually shown lighter or with a texture pattern
  • The edge with pre-drilled holes always goes on the inside of a joint, never facing outward
  • If a part is not symmetrical, look for a factory pencil mark or identify it by its hole pattern
  • Standard technique: lay all panels face-down before starting to assemble the carcass

Carcass Assembly Order

Most carcasses follow the same sequence regardless of manufacturer:

  • 1. Insert dowels into all designated holes
  • 2. Join one side panel to the base — do not fully tighten the confirmat screws yet
  • 3. Attach the second side panel
  • 4. Fit the top panel or horizontal rail
  • 5. Slide in the back panel — it squares up and locks the carcass
  • 6. Only once everything is square — tighten all confirmat screws fully
  • 7. Fit hinges and door panels last

When the Instruction Is Unclear

  • Look at the next step — the current step often makes more sense in context of what follows
  • Physically hold the parts together without fixings — test the logic of the joint before committing
  • Search for a video using the furniture's article number or construction type — most popular ranges are covered on YouTube
  • Do not tighten anything permanently until you are sure the orientation is correct

The golden rule: do not tighten any fixing fully until the whole carcass is assembled. Build it loosely first, check the geometry is square — then tighten everything. Undoing a fully tightened carcass is far harder than adjusting a loose one.

Common Mistakes When Reading Instructions

  • Skipping a step and moving on — most assembly errors come from this
  • Confusing similar-looking parts of different sizes — always check against the parts list
  • Using the wrong fixing — a confirmat screw instead of a wood screw or vice versa
  • Tightening an eccentric cam in the wrong position — it must click into a specific orientation
  • Forgetting to insert dowels before joining panels — means disassembling what you just built