What's the best way to improve a stale smelling house

Assuming you have an extractor fan in a bathroom get it switched out for one that’s on continuously. They pump fresh air in and stale air out.
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Don’t do this. You are trying to mask a stale smell by creating toxic indoor air pollution. Just open some windows when you are home. I only do once a week or so and my home smells fine.

https://pmc.ncbi.nlm.nih.gov/articles/PMC3018511/

My friend often buys these for me for Christmas and/or birthday. They are lovely!

Lots of good ideas on here already. Just be careful with plug ins as they are not great for your lungs especially with low ventilation and no good for pets, if you have any.
Does your bin lid close tightly? Ours didn’t and was the cause of a lot of our stale whiffs. I swear by zoflora and have a diluted solution that I spray in the sink plug hole before I go out. Extractors need cleaning too and often smell stale, maybe check those.

I suspect you have a whiff coming from somewhere and that’s where the lingering stale odour is originating. I had a slow leak from the dishwasher waste just dripping behind it it was tiny but created a stale smell as it dried that was hard to pin down. I’d check under sink cupboard drip tray from behind fridge, behind radiator, scrub out the bin.

Valentte do amazing reed diffusers and oil drops, I used to spend££££ on Ko Malone reed diffusers at the airport until I discovered them. The Rosemary one is my favourite, it smells fresh and clean.

Have you tried wiping your walls and ceilings? They get dirty too and can hold onto smells over time from things like cooking, smoking and drying clothes.

I'd have a look at what is causing the smells. Humidity or damp, pets, soft furnishings that need a good wash, carpets or rugs that need cleaning, laundry, bins, or just upping the cleaning tasks a bit. Don't add other smells to try to cover it up.

if you don't want to leave windows open all day- open at least one, as wide as possible, on each side of the house on each floor as soon as you get in. (creates a draft) making sure all internal doors are open. Leave them open at least 10 minutes.

And then leave them cracked open all night. (if you can, do the 10 min thing again in the morning. It is the German Way and it's pretty good.

Also check behind furniture that you rarely move, wardrobes, sideboards etc, to make sure there's no mould growing or whatever.

If you dry your clothes inside that could also be contributing.

Oh...missed the bit about coming home at 11PM. You obviously can't open all the windows then! But on the days you're home earlier, and when you're cooking, getting in the habit of letting the house air will help a lot.

I don't personally like artificial air cleansers or fresheners at all, and they're potentially not good for you.

I mentioned essential oils but you still need to be working with fresh air otherwise you're just masking the staleness.

Can you put your windows on a latch? This is what we do and we rarely even close them at night time through the spring and summer.

I got an air purifier off amazon with a little slot for essential oils, I have it set up in the upstairs hallway with lavender in and run it 24/7. It smells amazing when you come in the front door.

You need to remove the stale air and replace it with fresh air. Just adding more smells on top, even if they are nice smells, won’t help. Open windows and run the extractor in the kitchen to draw fresh air through the house.

Leave all of the internal doors open so that air can circulate.

Keep bedroom and bathroom windows open. Mine are open 24/7.

Sounds odd, but clean all your light fitting, on top of wardrobe&, behind radiators etc. Cleaners done typically do this, but if you do it every six months or so to clear any built up dust it will make a big difference.

I know you said you know all the things about ventilation, but it's really the most important thing by far.

When you wake up in the morning make it part of your routine to go around and open all the windows upstairs before you have your shower/get ready for work. Just before you leave, go around and close them all again. Even 5 or 10 minutes a day will make a big difference.

Do the same thing downstairs in the evening while you're cooking dinner (obviously skipping those windows that might cause security concerns if that's an issue).

Just doing that daily will help a great deal.

Make sure, if you do leave windows on the latch while out, that it doesn't invalidate your insurance!

When you're at home (weekend, day off, whatever) leave all the windows in the house open for a good, long while - I make myself a cup of tea and sit in the living room that faces the front for at least 30-45 minutes, that way I'm sure the whole house has got a good airing, and I don't have to worry that someone's going to crawl in through the windows!

After cooking just quickly spray some degreaser or cleaning spray on the splashback/counter tops/cupboard doors and wipe down so that you clear some of the potentially stinky grease. Obviously don't leave food or sorry dishes out. Empty the bins more often.

Wash curtains every so often as they can really hold on to smells.

Essential oils are lovely - I have a basket of pine cones in the front room that I use as a vehicle for oils to fragrance the air.

I'm the same - perimenopausal and my sense of smell has gone into overdrive. I used to think people were being a bit silly when they complained about smelling things too keenly but oh my god it's horrible when you can detect so many levels of odour!

Price's reed diffusers are great, I'd get a Chefs kitchen for the kitchen and an Open Window for everywhere else. Tesco tend to sell them for £4 at half price a lot.

When was the filter on the cooker hood changed last? How new/efficient is the extractor fan in the bathroom? Can you put safety catches on some of the upstairs windows so you can leave them cracked open? How often do you change tea towels/washclothes/bathroom mat/hand towels? When was the last time you put Mr Muscle down the kitchen sink?

All upstairs windows open all night when you sleep.

I would have thought it was against building regs to have an internal kitchen with no external ventilation? Does it have some extra strong extractor fan?

Like another poster I also use essential oils. I have lavender, peppermint and tea tree, and put a drop on a wet cloth and do the floor with it, also do the table, shelves with it. I think you should air in the morning while you get ready for work and then again in the eve for at least half an hour. make sure rubbish is taken out often. wash duvet in machine (large one at laundromat if needed) twice a year, sprinkle baking powder and tiny drop of essential oil on mattresses and hoover them, wash pillows in machine, wash or have dry cleaned coats that hang about a lot, sanitise shoes, do out clothes cupboards every few months... good luck!

Ahh ha. Perimenopause sent my sense of smell into overdrive, OP. It's natural for some women.
My windows all have trickle vents and I keep them all open. If you didn't know they were there you might not see them. I regularly wash my sofa throws and cushions, and have a couple of small dishes of bicarb dotted around to absorb smells. Agree with PP, plug ins and other artificial scented stuff just seems to add to a general stale smell. Fresh air definitely preferable.

Hate scented items, all they do is add another chemical smell. I think just airing it, as you say that it is clean.

Definitely leaving upstairs windows open all the time on a locked setting, it makes such a difference. To be honest, we tend to do that with downstairs ones as well, but live in a pretty safe area. I would be surprised if you didn't have that as it's standard, but if you own you can look at getting window restrictors which let you leave them open a bit more. But, they do need drilling into the window and frame.

Zoflora or bleach down your plug holes

😱

You need to have your windows on the latch at all times, and open the vents.