What goes at the bottom, what goes on top, and what takes nothing on top

The order matters more than the space. A badly stacked unit fills up half empty, and then makes you empty the whole thing to reach the box at the back. This is the order that works, with the real measurements of 50 things people actually store.

The short version, if you are in a hurry: first what can only go on the floor, at the back. Then what leans on its edge against the wall. On top of that, the columns of boxes — heavy ones at the bottom. And by the door, whatever you will need first.

1. At the back, what can only go on the floor

That is 8 of the 50: too heavy or too delicate to sit on top of anything else. They go in first because after that you are not moving them.

• Fridge — 0.6 × 0.65 × 1.8 m
• Washing machine — 0.6 × 0.6 × 0.85 m
• Dishwasher — 0.6 × 0.6 × 0.85 m
• Tumble dryer — 0.6 × 0.6 × 0.85 m
• Euro pallet (1.2 m high) — 1.2 × 0.8 × 1.35 m
• Half pallet — 1.2 × 0.8 × 0.85 m
• Metal filing cabinet — 0.45 × 0.9 × 1.3 m
• Small machinery — 0.6 × 0.8 × 1 m

The fridge is a case of its own: on top of not going on anything, it does not lie flat either. The compressor oil goes where it should not and you switch it on already broken. Upright, with the door slightly open, or it will smell.

2. What takes no weight at all

8 of the 50. Some cave in, others have no flat face to rest anything on. Put boxes on them and the boxes end up on the floor and the furniture scratched.

• Chair
• Television
• Fridge
• Bicycle
• Parasol
• Christmas tree and decorations
• Pushchair
• Display stand

3. Stacking to 2 m multiplies what fits

Storage units are 2.5 m tall, but the number that matters is 2: that is as high as you reach without a ladder. A column you cannot reach is a column you will never touch.

• ×7 Archive box0.28 m tall each
• ×6 Small box (40×30×30)0.3 m tall each
• ×5 Medium box (50×40×40)0.4 m tall each
• ×4 Large box (60×50×50)0.5 m tall each

Look at the order: the small box gives more layers than the large one. Counter-intuitively, to stack high you want the small box packed full, not the large one half-empty — a half-filled box caves in and takes the column with it.

The 50 cm left above can only be used one way: with shelving.

4. The same unit, stacked and unstacked

The same 20 items in the same medium unit. On the left, everything on the floor; on the right, stacked to 2 m.

5. What lies flat stops eating your height

16 of the 50 items in the catalogue can be laid flat or stood on edge. And that is not a detail: an item standing up takes up its whole column height, and lying flat it frees the lot for stacking on top.

• Step ladderfrees up 1.75 m of column
• Parasolfrees up 1.74 m of column
• Single bed (dismantled)frees up 1.7 m of column
• Single mattressfrees up 1.68 m of column
• Double bed (dismantled)frees up 1.65 m of column
• Double mattressfrees up 1.64 m of column

Careful with what does not lie flat, which is where people get it wrong: fridge, washing machine, dishwasher and dryer always stand upright. And the television on its edge, never face down.

6. Full table: what holds what

The same measurements our calculator uses to tell you what size you need. If something is missing, write to us and we will add it.

7. Four things not to do even if they fit

• Wrapping wood in cling film

  Plastic against wood stops it breathing and traps condensation inside. Use a moving blanket or an old sheet.

• Filling boxes only halfway

  A half-filled box caves in under the weight of the one above and takes the column down. Fill the gap with clothes or paper.

• Leaving the aisle until last

  Always leave a way through to the back. It sounds like wasted space until the day you need the box behind everything.

• Leaning things against the partitions

  Partitions separate, they do not support. Anything you lean on them ends up pushing your neighbour.