To ask you to help me find the mystery smell in my house?

[peachgreen]

My house smells like sour milk. It's HORRIBLE. I cannot for the life of me pinpoint what it is and I was wondering if anyone had any suggestions of what it could be, especially if you've had a similar issue.

It smells worst in the hallway, lounge and the dining room, gets slightly better in the kitchen and utility room. Downstairs toilet smells fine. It isn't coming from the fridge or freezer, or the sinks or dishwasher. The house is 1950s with solid poured concrete walls internally and externally so there's nothing in the walls. There is a big "basement" under the floor which is inaccessible without tearing up the carpet - but the smell isn't stronger lower down. And no, I haven't spilled milk anywhere!

We're generally a pretty clean household although I'll confess that with an excitable 1 year old I'm not quite as on top of things as I would usually be, but we're talking a week's worth of dust, not a month's worth of old food!

HELP. It's driving me bonkers.

I was standing under our electric shower when it blew and it took me about 10 seconds to register something suddenly smelled funny, like a fishy mushroom smell which I think was the plastic wires melting. Worth checking electrics - especially with the tripping

We have painted recently (well, a year ago) but we didn't use Valspar and the walls don't smell. We definitely have damp issues in this house - we had the basement treated when we moved in which seems to have solved a lot of the problems but it could be somewhere we missed (definitely no bodies though - at least not human ones!). Have now emptied the larder completely and no rogue potatoes (though I did find some pears that were past their best but they didn't smell!). DH washes and bleaches the bin when he empties it so it's not that.

@SpringForEver Really helpful checklist, thank you - will go through all those at the weekend and report back!

@IsoscelesSandwich Definitely not pregnant! And DH can smell it too.

Do you have any house plants? We had one in our office that smelt like sour milk - because everyone kept tipping their tea dregs into it!

Also, a culprit in my house was an old chopping plastic chopping board. It was tucked in a drawer and I could smell it every time I walked past.

Satsuma left in a Christmas stocking? I did that one year and the smell was vile.

Found it yet?

Oh gawd... what if OP took a point blank whiff up both nostrils and has been lying face down somewhere in her hallway for three days?!

Well I think we've solved it... during the search we found a TINY patch of mould behind the sofa - I mean about the size of your palm - just caused by condensation. It didn't seem to be the source of the smell but obviously I wiped it down and treated it while I was there. And now the smell has gone! So either it was a dead animal which has fully gone now or it was this tiny patch of mould!

No collapsing thankfully.

Suspect vermin

De lurking to say yay!

Great news that your smell is gone