Where did all the space go?

We moved into our current house 5 years ago, with one newly minted child (a few weeks old), and one part-worn canine. We bought it because it was in a nice area (next to a nature reserve); close to future schools (walkable with the chiildren); and a good-sized plot with a larger than average garden (for a new-build property at least). We expected to have to do some work on the house to bring it into our style (much more modern than the previous owners taste), but size wasn't really a consideration. It had 5-bedrooms at the time (we've since converted the box room to an en-suite for the second bedroom - now master); 3x reception rooms (conservatory; dining room; living room); a study; double garage; etc. Basically, all the elements in the right proportions for a family of our size (and with room for the addition of another head to the tribe, which came a couple of years later).

True to form, we did a little light work

• Converted bedroom 5 into en-suite for bedroom 2
• Converted bedroom two into master bedroom
• Fitted furniture for master bedroom; bedroom 2; and study
• New suite for en-suite (bedroom 2)
• New suite for downstairs cloakroom
• New flooring - lounge; hallway; study
• New carpet - pretty much everywhere else

All in, we probably spent about £25k on getting it up to a point where we were happy with the upstairs layout, and generally the property was modern and worked for us. It does appear, however, that there's an unwritten law of physics that says

Any family blessed with children will inevitably run out of space and find impracticalities at every turn in whatever dwelling they find themselves in.

Needless to say, we've started to feel the pinch in a number of areas

The little girl's bedroom is painfully small now that she's out of a cot and into a 'real' bed. We ideally need to give her some more space; sort out some plan around bathrooms (currently the boy has an en-suite, and she uses the family bathroom, which is fine until she's a little older or when we have visitors)

The children have enough toys to restock most floors of Hamleys, and as they get a little older are increasingly in need of a desk for homework etc. a playroom would be ideal where we can put a desk, house their toys, and give them some space away from the main family areas, but close enough that we can keep an eye on them.

The kitchen is probably the least functional part of the house (OK, maybe the conservatory, but that's a complete write-off) - it's dated, dark and not really the modern, centre of family life we'd like it to be. We really want a larger open-plan area where we can cook, entertain and generally do family stuff in. We have a good garden, so something that opens onto the greenery for the summer months would be ideal.

The conservatory is ridiculous - it flips from arctic to saharan temperatures, depending on the season, and has largely become a storage cupboard as a result. Depending on what the kitchen situation becomes (i.e. maybe a larger kitchen space, open to the garden) then the conservatory is somewhat surplus to requirements.

The previous residents attempts at garden landscaping aren't really holding up to modern family life, with walls crumbling; decks rotting; etc. Something low maintenance, with some grass for football, and an area where the kids can have some play equipment (maybe also a trampoline) are high on the list for this space.

The current floorplan is below, so you get an idea of the layout we have. It's not a small house, and our problems are clearly nice ones to have (I'm sure most 2x2 families would be more than comfortabke in a house like ours), but we work hard to pay for nice things, and one of those mice things is a house that functions as we need, and is a nice place to soend some time

We need to find an alternative solution to our current situation, whether that's to move to a new property that fits our current and future needs better, or adapt our current one to tick more of the boxes on our hit-list.