They have the whole world to choose from when deciding to where to fly next.
Flies getting through vinyl replacement window.
To prevent cluster fly infestation you could use following tips.
Cluster flies can enter your homes through the smallest cracks around door and window frames or through any other tiny unsealed opening.
So they spend the next ten hours bashing into the window trying to get out until they die of exhaustion or until they re swatted.
Then once they re in they just want to get out again.
The number one problem with vinyl replacement windows a loss of glass viewing area.
Your doors and windows aren t always closed.
These flies enter homes through cracks and gaps such as those found around windows.
Most are dead but i will see a few flying around.
Cluster flies look similar to houseflies but are slightly larger with overlapping wing tips when at rest.
Unlike brick or wood homes the sugar particles which may not be detectable to the human eye stick to the vinyl siding causing flies to gather.
As long as there s something inside the house to attract them and there usually is they will get inside in search for food.
You ve noticed a lot of draftiness and maybe even some operational challenges.
They make a buzzing sound and fly in a sluggish manner.
For starters the concept of a replacement window can be a bit of a misnomer and contribute to the issue.
But once in the building i think they got into air ducts and from there followed light sources trying to get out and we ended up with dozens of flies on an inside window like you said.
I still am not sure how or why the flies got from the bird to inside the house.
I would check your exterior walls patio yard etc for any remains.
They can get through any number of openings.
They fly around outside.
They don t really land anywhere.
Let s say you have wood windows in your home today.
I think they are getting through from a small gap on the window.
I have 7 windows in my house all of which have several dead flies.
Getting the dirt and dead flies out of your window tracks.
However there is an easy way to thoroughly clean the tracks that is quicker and not as.
You can see the gap in the 2nd picture on the bottom right.
Fill all the cracks or crevices in walls window or door frames with caulking.
When the strips get full you just slowly pull them off replace with new strips.
I cut my strips in half put 2 strips on the top window glass 2 strips on the bottom window glass.
The fly you see in your window may not be a housefly at all but a cluster fly.
But they manage to find a tiny crack in your window.
It s one of the ickier household chores.