Photos of the space.

Here’s a rough of what it might look like…

Thank you Kazzh, I'm hoping to get rid of that slanting space underneath. But thank you very much. Love the covered stsirs.

Boxing in under the stairs will make the room look smaller, and you haven’t really got anywhere else for a dining table.

I agree with Sarah. Replacing the spindles for glass could work.

The artex and fireplace is adding to the busyness. Could you take out the side bits of the fire? Tv to the right of the fire and sofa opposite with a chair to the left of the fire.

Go for roman blinds rather than curtains which encroach on the floor space. A mirror over the fire to make the room feel bigger. Opt for a dining bench at least on one side

My first thought was also to add an under stairs dining nook till I realised that your front door opens on to that space so it wouldn’t be practical. How about placing a small round dining table, with chairs that tuck underneath, into the corner where the yellow curtain is? And if you were intending to skim the ceiling you could take the opportunity to move the central ceiling light to a hanging pendant above the dining table. I agree with Minnie, the dated fire surround needs to go. If the radiator was moved it would allow space for an L shaped sofa to be placed along that wall. I’ve included a couple of ideas for the stairs and this would create a space to store coats and shoes and have a small arm chair for putting your shoes on. The chair could also be useful when you need more seating in the lounge. As far as a loo is concerned the only place a tiny one might go would be under the stairs but that would make your room even smaller!

Definetly agree with betty as it will be in theme with the firplace wood

However I would suggest to instal it from floor to ceiling or another alternative glass stairs and add handrail on the wall side as it wont be aproved in UK housing regulation without handrail.

You can add small handcraft radiator cover from wooden pallate that looks like small cabinet to cover the radiator or if you want to put sofa against it then create the cover like a long wall niche

Yes a handrail is a necessity. Whilst some radiator covers do look good I still think it would be better to reposition yours to allow a corner sofa to be placed against that wall and a table in the corner. Covering a radiator is never a good idea.

Opt for slatted unflammable covers and open sides on top of the cover that allow air to circulate freely, maintaining heat distribution while providing a stylish appearance. This cover actually to protect toddlers, pet and furniture touching the radiator when in use, some type of radiator can get really hot in contact. There even standarized brands for safety and improve heating distribution by limit heat loss like Arte Viva Radiator Cover

Thank you so much Sandra, Monnie01, Betty and Devrya. These are so helpful! There will be no fireplace and the radiator will also be in the corridor, just opposite the kitchen entrance so most of the suggestions work really well. It's a long road ahead but I'll share updates. Thank you so so much!

Could you supply the upstairs layout too please? It would help with planning where the loo could go. Are there only windows on one wall downstairs?

If the budget allowed, I'd look at removing the wall separating the kitchen and living room and make a corridor which could accommodate a small loo.

Here some idea if you planning to have small bathroom under the stairs and for the open plan kitchen be mindful of the space for a fridge in the corner, I advice to make the bathroom door open to outside or using sliding door so it not feel cramped when opening door.

I suggest you place two seater sofa on later closed off stairs wall and place swivel TV stand on the top left corner so it can be adjusted wherever you sit

for the radiator placement in the corridor I suggest you visit neighbor who has similar radiator placement and consider if its warm enough in winter cause it depends how well the heating distribution if it placed in different room

Dear Tab Darcy, that's the top floor. Thank you!

Devyra, that's a good point re the radiator in the corridor. I'll check this. I wont be making the kitchen into an open plan one so hopefully, that should be alright. Thank you for the understairs suggestions too. I'm grateful.