There are so many things to consider here. I would approach an architect and pay for a consultation. I have no idea about the regulations regarding extending a ground floor flat. Is it semi-detached? I read a reliable source that said that building costs had increased by 40% between 2020 and 2023. Supply and demand. I wouldn't rule out moving either to get the space you require. There is no cheap way of doing it. You could subdivide the main bedroom but I don't think it is big enough.

Say if you reduce the width of the shower (and fit a pocket door) move the bedroom door over to the left to create cupboard depth for a large utility cupboard on the right wall you could decide if you want to convert the bedroom into a kitchen/diner/sitting room with bifold doors to the garden, with the kitchen in one line on the right, sofa and 1.5m table on the left, it would be snug but if you do decide to extend at some stage the kitchen here would make sense, the two front rooms would become bedrooms.

Alternatively, you could turn the rear of the current kitchen into a single bedroom with bunk beds and the lean to as a toy store, opening the remainder of the kitchen into the sitting room in a U shape. I would still redo the width of the shower so you had enough space for overflow kitchen/utilty along the right wall of the hall.

On a budget seems very unlikely. Consult a local architect/builder.

Meanwhile: Is there another storey on top of the bedroom?

@Rinked no, there is no other story. It's a ground floor flat which was converted from a house into two flats. There is another flat above them. This is why I suggested an architect.

I meant neighbours :) aka another construction on top of the bedroom

Assuming there's a neighbour on top of the bedroom, assuming both layouts could get planning permission and assuming you have the budget, here are some scetches:

1. Add a 4x3.5m (give or take) bedroom to the rear, create a hallway towards it. But keep in mind the smaller bedroom needs to be 6.5m2 to officially be considered bedroom (for resale value). A 90cm hall plus 11cm wall would leave 215cm width, which is just enough for most bedframes.

2. Goodbye sunny front reception, turned you into bedroom.. Kitchen would become the master bedroom, as the front door needed that hallway. Open plan living moved towards the garden. Removed the narrow lean to to allow more daylight into the bedroom.

You could start looking for a 2-bed, but if the cost of extending is somewhat returned in sales value (and the location is good), i'd say go for it!

No hurries though, a cot can easily go in your bedroom for a year or so. ;)

Hi,

one option would be a very small side extension.

wouldn't give you anything spacious, but it might tick a lot of boxes.

Utilising the hallway to put in a galley kitchen, and turn the old kitchen into a bedroom.

If you didn't have money to extend, then you could just use the current bedroom as a living and dining area, but create a better connection with the back garden.

If the garden is quite large, creating a self-contained unit at the end of the garden could be a future project. Like kid's playroom or anything you might need.