It is really just a matter of removing the clutter around the grate and giving it a good cleanup. It is quite an interesting feature and will stand well on its own. I would remove all of the objects around it and clear out the grate. The modern stand of tools needs to be replaced with a simple set that matches the style of the fireplace. Not sure what the round item to the left is, but I suspect it might me a lighter of some sort. It and the jug seem to feel comfortable but the rest of the items need to be removed. As suggested above, a careful application of the appropriate blacking will do wonders, but even before that I would call in a chimney sweep to clean the flue and make sure it is in working order. Even if you do not plan to use the fireplace it is a good idea to know what the working status is. I imagine this is meant for coal burning, though I would not take my word on that. I have a gas fire with imitation coals that "burn" quite realistically. You can get them at a fireplace shop and they do indeed look like coal. You could use those if you do not plan to light them, or even use real coal to fill the grate. When I restored my fireplace and set in a coal basket I was lucky to talk to an old fellow who knew just how it should work. If you can't find good advice from a shop or chimney sweep then it would be fun to do do a little research at the library to find out how the fireplace was used and how it should look with proper accessories. I think you will be pleased with the result.

As an experienced architectural designer my answer deals with your specific problems, but also contains general advice which could be useful to other readers, so please don't be offended or take what I write personally... I'm just trying to help people. I notice your house has a massive external surface area with which to lose heat, plus lots of windows so it will not be an easy house to keep warm! It would be very sensible to check out your whole house internally and externally with an infra-red thermometer as this will show up the worst heat loss spots. They could be around window frames, doors, skirting, ceilings and these are the places to target your heat loss fighting energy and finance. Your problem could be caused by a whole range of issues. Do you have a suspended timber floor which is ventilated? Just like your open chimney, the wind will rob any heat from the room unless you stop it doing so. This would involve insulating the floor in some way, and if you were taking up the floorboards you would be wise to treat the joists (especially the ends) and check for evidence of mice, which can play havoc in cavity wall insulation. Taking up the floor is a very disruptive job, which is why it has not been done in my house. Untreated timber could rot if ventilation is restricted by close-fitting insulation. If you have an unventilated floor, it may not have any or enough insulation. Also, beware of internal insulation as a solution, as this makes your outside walls colder/damper and usually leads to later problems with damp/mould/rot and expensive remedial work, even structural failure. Make sure you follow the advice of a competent person who understands how complex building physics can be. (Building services engineer). Bay windows are usually really poor bits of construction... If your double glazing has a large gap between the panes of around 20mm, it may not be the real problem. If the spacers (between the glass) are shiny aluminium, this is not good, so if you ever replace the glazing, don't settle for anything less than Edgetech Superspacer or Truplas, the very best warm edge spacers available. I live in a 1930's ex council house and I have blocked the only remaining chimney with a massive bag of loft insulation. The floor was already overlaid with a cheap laminate floor, so the floor gets cold when the winter winds roar. Reflective blinds (checkout Reflex Rol) can be used, but with a bay window, fitting will be complex and heat will still escape around the edges of the blind. Reflective foil is able to bounce radiant energy away from itself, but there should always be an airspace on each side of the foil or the energy just conducts through to the cold side. If the window faces south, then blinds could make the room even colder, unless you always remember to raise them early each morning - the same goes for thermal shutters. My house in Somerset has a gas combi boiler which has hardly needed to come on at all so far this winter. My gas and electricity comes from EBICO, as they have no standing charges. I have insulated the house externally with 50mm of Celotex, covered with treated battens and Marley Cedral weatherboard (which does not rot) and only adds around 80mm to the wall thickness, plus Cedral is perfect for eaves boards and soffits. (You can paint it whatever colour you like). This, plus a porch outside the front door has made a massive difference to my warmth as I am 70 and now live on my own. The attic has been properly insulated and boarded to become an unofficial room. I am lucky to have two unshaded windows that face south and they bring in lots of free energy. I am not stupid and I'm often in and out to my garden, so in winter I wear a vest under my T shirt, as well as a fleece and longjohns under my trousers (get them at Lidl) which is also a good place to buy LED lights. Always start with energy conservation and insulation rather than things that burn timber or fossils fuels and ignore the real problem. I would avoid burning wood, given the state our atmosphere and lungs are in. We are not cave men anymore and should be evolving. New energy efficient houses sometimes feature large south-facing PV roofs which directly heat a central water tank or can feed electric underfloor heated zones - and just like my 1970's experimental solar house, these super-insulated dwellings do not have a 'normal heating system'. I can't stand curtains, they look a mess, often block out solar radiation / light and have to be washed. I like close-fitting wooden floors which you can simply sweep with a brush and run over with an upright vac-cleaner. Tiles are a pain to keep clean and can break your hip as well as things you drop. We can save lots of money and energy by not buying things that need to be washed and dried, as well as things we really don't need!

Nice picture. Is it actually a real painting? If so I wouldn’t ‘modernise’ that, but painting the frame in your Lamp Black will certainly update it. May be a ‘safe’ colour but at least you won’t make the wrong colour choice. 🙂 Out of interest, what size is it?

Hannah W yes the blocked wall was double doors, part glazed. I couldnt tell you a cost I’m afraid as my husband blocked up the wall, he’s not a professional (we can see the outline on the other side 😁) but it didn’t take too long and was just a case of some stud work, plasterboard and plastering (my husband can plaster too as he did a course years ago to cut down labour costs rather than have tradesmen in).