Measure once. We'll do the worrying.

The golden rules

• Measure in millimetres. Every size on our site is in mm, so there's nothing to convert.
• Measure every gap in three places. Top, middle and bottom for a width; left, middle and right for a height. Walls are rarely straight.
• Give us the smallest. Your piece has to fit the tightest point.
• Look for things in the way. Skirting boards, sockets, switches, pipes and picture rails. Note how far they stick out and how high they are.
• The sizes are yours. We make it to the measurements you give us, so measure twice.

Alcoves: three numbers, five minutes

1. Width, three timesAt the top, the middle and just above the skirting. Alcoves are rarely square, so give us the smallest.
2. HeightFloor to ceiling, or to the picture rail if you want to stop under it.
3. DepthFrom the back wall to the front of the chimney breast, if you want it flush.

Under the stairs: measure the triangle

1. Width along the floorFrom the wall at the tall end to where you want the storage to stop. Measure at floor level and halfway up.
2. Height at the tall endFrom the floor to the underside of the stairs, against the wall.
3. Height at the short endFrom the floor to the underside of the stairs where the storage stops.
4. DepthFrom the back wall to the front edge of the stairs (the stringer), if you want it flush.

Hallways and landings: leave room to get past

1. WidthWall to wall if it's a recess, or the length of wall you want to use. Look out for door frames and radiators.
2. Depth you can spareMeasure the hallway width, then decide how much you can give up. Most people want at least 800mm left to walk through.
3. HeightFloor to ceiling for a tall cupboard, or to just under a light switch or a coat hook for a bench.

Eaves and lofts: measure where the roof meets the wall

1. WidthThe length of wall you want to use, at floor level.
2. Height at the tall endFloor to ceiling where the slope starts, or where you want the storage to start.
3. Height at the low endFloor to the slope where the storage stops.
4. DepthHow far into the room you want it to come.

Box rooms: measure the room and the bulkhead

1. WidthWall to wall, at the top, the middle and the floor.
2. HeightFloor to ceiling.
3. The bulkheadIts height from the floor, its width and how far it comes out from the wall.
4. DepthHow far into the room you want the piece to come. Leave space for the door to open.

Chimney breast and TV wall: measure each part of the wall

1. Each alcoveWidth in three places, height and depth, as for any alcove.
2. The chimney breastIts width, and how far it stands out from the alcove walls.
3. Under the TVThe height of the TV's bottom edge, so the media unit sits below it.

Bedrooms: measure the wall you're fitting

1. WidthWall to wall, at the top, the middle and the floor.
2. HeightFloor to ceiling, at both ends. Ceilings slope more than you'd think.
3. DepthWardrobes need about 600mm for hangers. Check the door and the bed still have room.
4. In the waySkirting, coving, sockets and switches: where they are and how far they stand out.

Not sure about something? Email a photo to hello@tamedspaces.co.uk and we'll help.