Loud banging in crawl space - not rat or bird

Last night, and for past half hour again, have had a rhythmic banging noise from an area over sitting room ceiling and in behind an upstairs bedroom wall. I've called it a crawl space but it's actually sealed. It's beside a dormer window and below the attic - out front. It's very specific to that area. There is a chest of drawers near that corner in the bedroom but it's been there for years and isn't that heavy.

In the sitting room itself, there is a tv in that corner. The aerial is in the attic above sitting room and bedroom.

The banging was regular and loud. Not a rat scurrying around, not a bird flying into something, almost like someone slapping the joists every 30 seconds.

I've switched off the plugs behind the tv...and it's stopped. So assuming it's linked to the electrical circuit, and not the house settling or some plumbing issue...there are no pipes in that corner anyway.

Any ideas what might cause it? Could it be water dripping on a wire? Would that make a bang? Something sparking?

Bonzo Delaney

Deleted User wrote: »

Last night, and for past half hour again, have had a rhythmic banging noise from an area over sitting room ceiling and in behind an upstairs bedroom wall. I've called it a crawl space but it's actually sealed. It's beside a dormer window and below the attic - out front. It's very specific to that area. There is a chest of drawers near that corner in the bedroom but it's been there for years and isn't that heavy.

In the sitting room itself, there is a tv in that corner. The aerial is in the attic above sitting room and bedroom.

The banging was regular and loud. Not a rat scurrying around, not a bird flying into something, almost like someone slapping the joists every 30 seconds.

I've switched off the plugs behind the tv...and it's stopped. So assuming it's linked to the electrical circuit, and not the house settling or some plumbing issue...there are no pipes in that corner anyway.

Any ideas what might cause it? Could it be water dripping on a wire? Would that make a bang? Something sparking?

If it was electrical I'd presume the circuit board would trip out
I'd might be loose roof felt flapping if the attic space is draughty
Is the house old

shaunr68

I'd agree with the above, something flapping about seems a likely culprit. When you said you turned off the plugs, did you switch off the sockets at the wall? Can't see that it would make any difference if there was a wiring fault. Perhaps it was just a coincidence that the noise stopped at that point. Did it re-start? Could it be dripping, does it happen in dry weather?

dathi

could be "water hammer" in a plumbing pipe. after a toilet has been flushed as the ball cock stops the water the pipe vibrates.

greenhorn22

+1 on the pipe theory

Calahonda52

Is this a brand new problem?
re this
I've switched off the plugs behind the tv...and it's stopped.
did you use the mcb on the consumer unit to kill the power to the plugs or just offed the switches.

Do you have down lights up into that area or sockets, U se a little cctv camera that fits through the downlight, assuming no insulation and flower pots in the way

Guys, he says no pipes....

Thanks for replies.

There should be no pipes in that area. Plus it didn't follow any toilet flushes.

Just switched off the sockets at the wall itself.

The bangs were really loud, not just noise or bumps or even drops on plaster board, but like someone banging regularly with their fist on the other side. I was out for the day but my wife says she turned on the switches about an hour later...and 20 minutes after that the banging started again, so she turned them off and they stopped again.

Bonzo Delaney

Deleted User wrote: »

Thanks for replies.

There should be no pipes in that area. Plus it didn't follow any toilet flushes.

Just switched off the sockets at the wall itself.

The bangs were really loud, not just noise or bumps or even drops on plaster board, but like someone banging regularly with their fist on the other side. I was out for the day but my wife says she turned on the switches about an hour later...and 20 minutes after that the banging started again, so she turned them off and they stopped again.

But .... But the switches have no effect on the cables supplying power to the sockets at all , the switch only isolates the appliance its serving. I dunno guess it's time to cut a hole in the wall at the back of that press and have a look what age is the house.

Do the wires to the socket heat up in any way when appliances are on? Thought it might be linked to that.

House is 10 years old. Wooden flooring so it does have a bit of that "can hear footsteps upstairs" thing that's so common, but otherwise not bad for sound.

The other alternative is a Japanese ghost in the space...I have seen The Grudge...

Bonzo Delaney

It could be the roof felt flapping in the gutter in the wind I've seen it once before sounds like a clapping noise other than that I'm at a loss

Calahonda52

Just guessing
Have a close look outside at the eaves and dormer to see any sign of birds nesting in there
Is the aerial cable flapping in the wind.
missing roof tiles

Dtp1979

Do you have a stove in the room or a back boiler?

aujopimur

Illigal immigrants?.

No stove or back boiler.

Couldn't see anything loose or flapping, wasn't windy Sunday morning. It has since stopped though.

Dtp1979

[Deleted User] wrote: »

No stove or back boiler.

Couldn't see anything loose or flapping, wasn't windy Sunday morning. It has since stopped though.

Could've been an old mouse trap that was still set. Maybe a rat or mouse got caught in it, put up a good fight then died

Dtp1979

Dtp1979 wrote: »

Could've been an old mouse trap that was still set. Maybe a rat or mouse got caught in it, put up a good fight then died

No, can't access the area at all so no traps in there.

Plus, unfortunately, I know the death rattle of the rat. The furious scraping and thumps. This was regular, one big bang every 30 seconds for minutes on end.

Mrs cockett

A Mystery

cupan_tae

unless a mouse something chewed a cable, and when the circuit is on it is spazming ?

Sounds like you'll have to get into the crawl space to figure it out ?

Thought of one possible explanation.

We got footpaths put in a few weeks ago. Lot of rain last weekend and maybe they settled slightly and a cracking noise went up a wall and reverberated off the joists in that corner of the house?

Possible?

Calahonda52

Deleted User wrote: »

Thought of one possible explanation.

We got footpaths put in a few weeks ago. Lot of rain last weekend and maybe they settled slightly and a cracking noise went up a wall and reverberated off the joists in that corner of the house?

Possible?

A bit far out perhaps?
have you thought about how to get a look see without serious disruption/repairs?
Any pictures of the outside?

Harry Palmr

Woodwork contracting? My attic joists creak and bang at night in the summer after a hot day.

Calahonda52

Calahonda52 wrote: »

A bit far out perhaps?
have you thought about how to get a look see without serious disruption/repairs?
Any pictures of the outside?

A look see would mean going through a bedroom wall. Only plasterboard or whatever they call it...but still unsightly and knowing me and diy will be left there!

As it's stopped since Sunday, happy to let it lie. Might ask an engineer.

Calahonda52

Deleted User wrote: »

Might ask an engineer.

You are asking one:)

Perhaps consider cutting a hole to take a double socket, and just put a blank plate over it.
The hole needs to be cut the right size for the dry wall socket box and make sure its horizontal
https://www.youtube.com/watch?v=B5tdMUE28Zo

You could then peep in there with maybe a small cctv camera on a stick, Thats what I use for this sort of stuff
Or this day and age a video on the phone with a selfie stick?

above assumes no insulation like rockwell in between the wall stud: insulated PB not a problem

Bonzo Delaney

Harry Palmr wrote: »

Woodwork contracting? My attic joists creak and bang at night in the summer after a hot day.

Also a common thing would be the PVC gutters contracting after a hot day.

recipio

Could a bird have gone into the space.? They can flap about for days on end before expiring.

Bonzo Delaney

It's a good priest is what you need.

recipio

recipio wrote: »

Could a bird have gone into the space.? They can flap about for days on end before expiring.

Thought of that but the noise and the regular nature of the bangs...it wasn't a bird or rat thrashing about.

whizbang

I have a cheep LCD TV on a wall mount on a partition wall. For a couple of hours after switch on, and again after switch off, the plastic case expands and contracts with an unbelievable loud bang.
Its amplified by the wall mount onto a stud wall, but still amazingly loud.

Its only late at night that I notice it, because of movement around the house, but it wakes me if i'm asleep.