flys everywhere!!

[GoSuckEggs]

we have just moved into a new house and there are LOADS of flys in the conservatory. there are also quite a few dead on window sils around the house.
I hoovered the conservatory, but then there are just more the next day.

what on eart could be causing so many flys?

Check any plants. One of my pot plants got infested and seemed to be a breeding ground.

Any air vents? If so might be breeding in there? And also check any little tiny gaps around the doors.

Dead creature under floorboards or in cavity wall?

Google cluster flies, with the lateness of summer it would be about right.

Cluster flies tend to get into lofts or other concealed areas and return to the same house each autumn when they lay their eggs. Warm weather causes them to come out and if they can't get out of the house they die, usually on window sills....

You may notice clusters of sleepy flies on your roof or external walls as the weather warms up as they have to warm through before they can fly. Likewise in autumn you may see them clustering again as they return to hibernate.

Pigs to get rid of too, we had them in an Army married quarter.

all of my plants came from my old house, there was lots of flys here before we moved.

no floorboards or wall cavitys.

these are not small flys, they are normal (bottlenose?!) flys.

did previous owner's wife or husband go missing unexpectedly?

is there a new floor or patio?

Could it be a dead bird in the chimney?

or, as it's a conservatory, it might have been carelessly built interfering with a gully or manhole cover, or damaging the drains.

look at and sniff the floor and lowest part of the walls for signs of damp. Houses built before plastic drains have clay pipes and gullies, which break when subsidence occurs, or tremors during the 1939/45 Unpleasantness.