DIY GUIDE · HOME REPAIRS & HANDYMAN · CHECKED 2026-10
How to assemble flat-pack furniture without ruining it
An hour to a day, depending on the piece. €86–192 in tools you keep.
The order of work, the check that catches a misbuild, and why a tall unit must be anchored.
- Every step, start to finish
- Checked 2026-10 — sources at the end
- Honest about when to call a pro
FIRST, THE HONEST ANSWER
Do it yourself, or get a handymen?
Do it yourself if…
- You have the instructions and all the parts
- You have a clear floor bigger than the assembled piece
- You can get a second person for anything tall or anything with a door
- You are willing to spend twenty minutes sorting fittings before you start
Get a pro if…
- It is a fitted wardrobe or anything that is scribed to the wall
- The piece is very large or very heavy and you have no second pair of hands
- Parts are missing or damaged — get those first; assembling around a damaged panel wastes the piece
- It needs to be fixed into a wall you are unsure of: dot-and-dab plasterboard, lath, or a wall with cables and pipes in it
Safety first
- ANCHOR ANYTHING TALL TO THE WALL before you load it. A chest of drawers with a drawer open has its weight well forward, and a child climbing it is the hazard this fixing exists for.
- Two people to stand up anything over about a metre and a half. A half-built carcase is floppy until the back is on, and it racks or falls.
- Lift with your legs and get the load close to your body. Flat-pack cartons are heavy, awkward and have no handles, which is exactly the shape that hurts backs.
- Check for cables and pipes before drilling a wall fixing, particularly above a socket or a switch, and use a detector rather than hope.
- Keep the small fittings off the floor and away from small children and pets — cam bolts and dowels are a choking size.
- Mind the sharp edges on cut chipboard and on the metal runners, and keep the knife cuts away from your other hand when opening the carton.
| MATERIAL | COVERAGE | FOR THIS JOB |
|---|---|---|
| Wall-fixing kit suited to your wall | One per tall unit | Plasterboard anchors or long frame fixings for dot-and-dab |
| Felt pads | A pack | Under the feet, so the piece slides rather than tears the floor |
| Wood glue | Optional, for dowels only | A drop in each dowel hole on a piece you will never dismantle |
How long it takes
about 90 minutes for a simple unit, three hours with doors — a low-clutch driver and a square
The sorting time is not overhead. Nearly every misbuild is a wrong fitting in the right hole, and sorting is what prevents it.
A cordless driver speeds the job up and is also how most flat-pack is destroyed. Set the clutch low, or do the final half turn by hand. Chipboard strips instantly and a stripped hole holds nothing.
Carcases go together slightly out of square and stay that way: doors then bind and drawers rub. A cheap engineer's square used before the back goes on is the single most useful tool here.
The fixings in the box suit solid masonry. Plasterboard needs proper plasterboard anchors; dot-and-dab needs a fixing long enough to reach the blockwork behind the void. The box's own screws are the wrong answer in most modern homes.
Assembling on a hard floor scratches the faces you will see. Work on the carton you just opened.
Not an efficiency — a half-built wardrobe is floppy until the back is on, and it racks or falls if one person tries to stand it up alone.
THE PART THAT DECIDES THE FINISH
Before you open a single bag
Everything that goes wrong in this job is decided in the first twenty minutes. These are the cases.
A clear, protected floor
The baseline.
- Clear a space bigger than the finished piece, with room to walk around it
- Lay the flattened carton or a blanket down and build on that
- Get the lighting right — cam locks and dowel holes are easy to mistake in poor light
- Move the door out of the way if the finished piece will not fit through it
Parts and fittings, counted
The step that prevents the stopped job.
- Lay every panel out and check it against the parts list, face up, in build order
- Sort the fittings into a tray or egg box — cams, cam bolts, dowels, screws of each length
- Check for damage now; a chipped edge or a swollen corner is a replacement, not a build-around
- Keep the fittings bag; the spares in it are the ones you will need
Reading the instructions all the way through
Twice as fast as not.
- Read to the end before step one — flat-pack instructions routinely require a panel to go in before something it seems unrelated to
- Note which panels are handed: many look symmetrical and are not
- Note the orientation of pre-drilled holes; the shallow ones are for screws and the deep ones for dowels
- Identify which step is the one that needs a second person, and arrange for them
Working out which way a panel faces
The commonest permanent error.
- Pre-drilled holes tell you: a face you will see has no holes in it
- Edge banding is on the visible edges; a raw edge faces inwards
- Lay panels in the orientation they will end up in, not in a neat stack
- If you cannot tell, stop and compare it with the mirrored panel — one of them will tell you
Plasterboard, dot-and-dab, or solid walls
Decides the anchor before you need it.
- Tap the wall: a hollow sound is plasterboard, possibly dot-and-dab over block
- For dot-and-dab, the fixing must reach the blockwork behind the void — the box's screws will not
- Use a detector and check for cables and pipes before drilling, especially above a socket or a switch
- Solid masonry takes the supplied plug; everything else needs a fixing chosen for it
Tall units, and the anchoring rule
The one safety issue in this family.
- Anything tall and shallow — a bookcase, a chest of drawers, a wardrobe — must be anchored to the wall
- A chest with an open drawer has its weight far forward; a child climbing it is the known hazard
- The anchor goes in before the piece is loaded, not when you get round to it
- If the wall will not take a fixing, the piece needs relocating rather than leaving loose
THE JOB
How to assemble flat-pack properly
Unpack and lay everything out
15 minOpen the carton flat and use it as your work surface. Lay out every panel face up, in roughly the order the instructions use. Keep the fittings in their bags until the next step.
- Do not stack panels on top of each other — that is how faces get scratched
- Check every panel for chips and swelling as you lay it out
- Keep the carton; you need it as a surface and you may need it for a return
Mistake to avoid: Building on a hard floor. Every scratch is on a face you will look at for years.
Count and sort the fittings
15 minSort into a tray: cams, cam bolts, dowels, each length of screw, handles. Count them against the parts list.
- An egg box or a muffin tin is the right tool for this
- Count now: a missing cam stops the build, and claims are easier before you have built half of it
- Group by step if the instructions number the fittings
Mistake to avoid: Working out of the bag. A 15 mm screw in a 12 mm hole goes straight through the face, and you will not notice until you turn it over.
Read the instructions to the end
10 minAll of them, before step one. Note the handed panels, the orientation of the pre-drilled holes, and which step needs two people.
- Note the step that needs help and get the help lined up
- Mark handed panels with a pencil on the inside face
- Check how the back panel attaches — it is often the step that fixes the whole thing square
Mistake to avoid: Starting at step one and reading as you go. Flat-pack instructions regularly need something done early that only makes sense later.
Fit the dowels and cam bolts
20 minPush dowels into their deep holes and tap home with the mallet. Screw cam bolts into their faces by HAND until the shoulder meets the board — not tight, just seated.
- Hand-tighten cam bolts; a driver strips the thread in chipboard instantly
- Dowels go in the deep holes, screws in the shallow — check before you tap
- A drop of wood glue in each dowel hole if you will never dismantle it
Mistake to avoid: Driving cam bolts with a power driver. They strip, and a stripped cam bolt hole cannot be repaired — the panel is finished.
Assemble the carcase loosely
25 minBring the panels together and engage the cams, but turn them only part way — enough to hold, not enough to lock. The carcase should still be slightly adjustable.
- Loose first, always. A fully locked cam on a misaligned panel is permanent
- Work on the floor rather than upright; a loose carcase racks under its own weight
- Check each joint is seated before moving on; a dowel not home holds the panel proud
Mistake to avoid: Tightening each joint fully as you go. The last panel then will not fit, and nothing will move to let it.
Check it square, then lock the cams
15 minMeasure both diagonals — they should match — and check the corners with a square. Adjust until it is right, THEN turn every cam fully home.
- Equal diagonals is the test; a square only checks one corner at a time
- This is the moment the piece becomes permanent, so take the two minutes
- Tighten cams in opposite pairs, like wheel nuts, so nothing pulls out of square
Mistake to avoid: Skipping the diagonal check. An out-of-square carcase means doors that bind and drawers that rub, and after the cams are home there is no fixing it.
Fit the back panel
15 minThe back is what holds the carcase square for the rest of its life. Check the orientation — one face is finished — and fix it with the pins or screws provided, starting at the corners.
- Finished face outwards; a back panel on inside out is visible from the room
- Start at the corners and work along, keeping the carcase square as you go
- If it is pinned, support the carcase edge so the pins do not bounce the panel
Mistake to avoid: Nailing the back on before checking square. It locks the error in, and the back is the hardest part to remove without damage.
Hang the doors and fit the drawers
30 minFit the hinges, hang the doors, then adjust them on the hinge screws until the gaps are even. Fit drawer runners level and square.
- Adjust the hinges rather than accepting the gaps — that is what the screws are for
- Even gaps top and bottom matter more than either door being perfectly level
- Check a drawer runs fully in and out before fitting the next
Mistake to avoid: Treating uneven door gaps as a fault in the piece. Almost all of it is hinge adjustment, which takes five minutes.
Stand it up — with help — and anchor it
20 minTwo people to stand it up. Level it with the adjustable feet or packers, then fix it to the wall with an anchor chosen for YOUR wall, checking for cables and pipes before drilling.
- Two people, no exceptions, for anything over about a metre and a half
- Dot-and-dab needs a fixing that reaches the blockwork; the box's screws do not
- Use a detector before drilling, especially above a socket or a switch
Mistake to avoid: Leaving the wall anchor until later. A tall unit is at its most dangerous empty and unanchored, and 'later' is how it stays.
Load it and check again
10 minLoad from the bottom up. Open every door and drawer, check the gaps have not moved, and re-check the anchor is tight. Fit felt pads if it sits on a hard floor.
- Heaviest items lowest — it is both more stable and better for the carcase
- Re-check the door gaps loaded; a shelf's weight can change them slightly
- Keep the leftover fittings and the instructions together with the model number
Mistake to avoid: Loading a unit before anchoring it. That is the exact state in which these fall over.
The four mistakes that ruin flat-pack
- Using a power driver on cam bolts and screws — chipboard strips and the panel is finished
- Locking the cams before checking the diagonals
- Fitting the back panel before the carcase is square, or with the finished face inwards
- Not anchoring a tall unit, and loading it anyway
Stop here and get someone in
- It is a fitted wardrobe or anything scribed to the wall — that is joinery, not assembly
- The wall will not take a fixing and the piece is tall: it needs relocating or a different anchor, not leaving loose
- Parts are missing or damaged — get the replacement before you build, not after
- The piece is too heavy or too large to handle with the help you actually have
| WHAT YOU SEE | WHY, AND THE FIX |
|---|---|
| A screw hole has stripped | Chipboard has no thread left once it strips. Pack the hole with slivers of wood and glue, let it set, and re-drive by hand — or move the fixing slightly if the design allows. |
| A screw has come through a visible face | The wrong length went in a shallow hole. Back it out, fill with a matching wax or filler, and use the correct screw; the mark will show slightly but the panel is usable. |
| The doors do not line up | Almost always hinge adjustment rather than a fault. Adjust on the hinge screws for height, depth and side-to-side until the gaps are even. |
| The carcase is out of square and the drawers rub | The cams were locked before it was checked. Loosen the cams, square it with the diagonals, re-lock — if the back is already pinned on, that has to come off first. |
| The back panel is on inside out | Remove the pins carefully with pincers and turn it round. Do it now; it is visible from the room and it gets harder once the piece is loaded. |
| A cam will not grip | The cam bolt is not seated to the right depth, or the cam is upside down. Check the arrow on the cam points at the bolt, and that the bolt's shoulder is against the board. |
| A panel is swollen or chipped out of the box | Do not build around it. Claim the part — an assembled piece with a damaged panel is far harder to put right than an unopened one. |
| The piece will not fit through the door now | Measure before building, not after. Some pieces can be partly dismantled; a back panel that has been pinned usually cannot go back on as well. |
WHAT YOU SAVE
What it costs to do it yourself
| Cordless driver with a clutch | €45–110 |
|---|---|
| Engineer's square, mallet, hex set | €25–45 |
| Wall-fixing kit for your wall type | €10–25 |
| Felt pads and sundries | €6–12 |
| Total, first time | €86–192 |
| DIY total | €86–192 |
Guide prices compiled by the Locufy team from published Irish and UK provider price lists and 2026/27 cost guides. Updated 2026.
All of it is kit you keep, and an assembly service for a single wardrobe usually costs more than the whole list — the price guide has the band.
RATHER NOT?
Furniture assemblers near you, with prices shown
The ones who cover your area, nearest first, with one score from every review. No account needed to look.
Or post the job free and let them come to you.
With the model number, in a labelled bag taped inside the piece. You will want them if you move.
Fixings settle, especially in plasterboard. Thirty seconds with a screwdriver.
Loaded and lived with, the gaps often want a small tweak. That is normal, not a fault.
Before you slide it anywhere. One drag across a wood floor undoes the floor.
Assembling flat-pack furniture: questions people ask
For the long carcase screws, yes, with the clutch set low. NOT for cam bolts and not for the final half turn — chipboard strips instantly and a stripped hole cannot be repaired. Seat cam bolts by hand.
Almost always hinge adjustment rather than a manufacturing fault. The hinge screws adjust height, depth and side-to-side; even gaps top and bottom matter more than either door being dead level.
For anything tall and shallow, yes, and before you load it. A chest with an open drawer carries its weight well forward, and a child climbing it is the hazard the fixing exists for. The box's own screws suit solid masonry; plasterboard and dot-and-dab need fixings chosen for them.
The pre-drilled holes and the edge banding tell you: a face you will see has no holes in it, and a raw unbanded edge faces inwards. Lay panels out in their finished orientation rather than in a stack.
Loosen the cams, square the carcase by measuring both diagonals, then re-lock in opposite pairs. If the back is already pinned on it has to come off first — which is why the square check comes before the back.
For a single bedside unit, no. For a wardrobe, a wall of units, or anything you would be standing up alone, often yes — and the price guide has the band so you can compare it against the tool list above.
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