Fish Smell in House

14 Sep 2007
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United Kingdom
How discouraging.....the unexplained fish smell that I discussed on this site last fall has returned. I though it had disappeared, but's back. This is too strange. I have exhausted all possibilities from electrical, plumbing, dead animals....even ghosts.

Can someone tell me what sort of a professional it is that I should have in here to investigate this? Electricians and plumbers have all shrugged and left, leaving me with nothing but a bill for hours of their investigative time.

Any theory would be appreciated. :cry:
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Getting warm again, sounds like something is decomposing!
Did your plumber check the traps in your bath, shower, basin ect?

Hair and other debris can sometimes collect in these traps and if said debris gets stuck between the water in the trap and the trap outlet can empty the trap via capilliry action therefor allowing bad smells to enter from the drain.

There are a few factors regarding traps not working correctly. Cheap shallow ones can dry out, Badly installed waste pipe can cause vacum situations which will pull the water out of a trap. etc etc.

This may not be the case but i'd just check them anyway.
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I had a nasty nasty fishy pong in the kitchen and it took me a week of searching and i did find out what it was and might be worth looking.

If you have one of these huge upright fridge/freezers pull it out and look at the waste tray at the bottom -

Ours was full of rotting, mouldy yoghurt, milk, and water jesus it ponged.

pulled out - washed, boiling water and washing up liquid and around bottom of fridge. Sparyed some dettol anti bac - put everything back and within one hour the smell has gone - and not seen again...

Yes, we have kids, so that explains the spilt, milk and yoghurts :)

Good luck..
try WMI (waste management industries) or your local garbage pickup .
they use a powder for their garbage containers that will kill anything.
Next try a carpet cleaner, they have a similar product to clean and de-smell carpets when someone dies in a house.
good luck.
only in canada eh!
"Any theory would be appreciated"
Have you checked some (or all) of your light bulbs? I know, from experience, that fairly old light bulbs, especially if they are not in regular use, do give off an offensive smell when they warm up. I don't know the cause but I assume that it is a collection of debris, insects etc, which collect on the bulb and start to "cook" as the bulb warms. It seems that the light does not have to be on, as the smell will be apparent, especially in a closed room, where the light was on during the previous evening.
Maybe you have it figured out by now and I know that you mentioned checking electrics but:

As Watchmaker said it could be light bulb heating up the old holder. Shorts in electrics in old plastic fittings can cause the plastic to heat up and give off the offensive odour as well.
As Tony wrote - it's not the bulbs but the plastic bulb holder, when the plastic gets hot it gives the fishy smell, that brittle plastic being urea formaldehyde, both of which chemicals have their own unpleasant smell.

You have probably got a 100w bulb in a holder marked for maximum 60w.
We had this when we bought our new house.

We were convinced it was the previous owner - hiding a kipper under the floorboards. It turned out to be the plastice light fitting.
Been working on a new build the last couple of weeks and the joiners have been cutting and installing Kingspan insulation in the roof before boarding over. The sun's been beating down and the whole top floor stinks like fish. Maybe it could be this?
Do you have a moss problem on the roof, porch, flat roof.... decomposing moss smells fishy, could be in the gutters or flat roof and smells gets in via vents. worth a try
is the house builtr on a concrete raft, or is there soil underneath?

Is the subfloor damp?

Have you had a sniff under the floor?

My money for a fishy smell would always start with an overheating thermoplastic electrical fitting though.

I'd change any filament-type bulbs for compact fluorescents (energy saving lamps) as they run far cooler as well as using 1/5th the electricity.

Possibly even try turning off the elctricity for a day ot two (preferably while you are away) to see if it makes a difference. I presume you can isolate your circuits one at a time.

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