Does anyone else have a problem with velux windows and flies?

[2MwahHaHaHappy]

We moved into this house nearly 2 years ago, it's originally a bungalow that the roof has been converted and velux windows put in. Last autumn, we suddenly had a problem with an influx of flies, and only affecting these upstairs windows. And now it's happening again . Honestly, it's like the swarm up there today. I think it might be related to the weather - as the air gets cooler, when the sun's out the windows warm up and the flies are attracted. But it is just revolting, hoardes and hoardes of flies, inside and out. Does anyone have the same, or have any suggestions as to how to tackle the problem (other than daily trips round with the hoover!)? TIA

We have velux windows in our converted loft, and have never ever had a problem with flies. Not even when we were growing maggots in our wheelie bin.... (insert puky emoticon here)

Are you sure it is the windows? Perhaps something dead in the gutter attracting them?

Maggots . There's no smell of anything dead in gutters, plus it's just strange that it's the same time each year. I think the windows are dodgily put in, it shouldn't be so easy for flies to get into the house through them, should it?

Mmm, you may be onto something there...
Get a reputable builder in to check the fitting - I can't think of any other reason for your unwanted houseguests...

What - dodgy fittings in your house???

I don't believe it.

We have 3 really high veluxes over our kitchen and dining room but haven't noticed an excessive amout of flies.

What we do get, however, is that any fly or wasp that comes into the house ends up by the veluxes (attracted by the light and think they can get out maybe??) so we end up having to get the long pole to open them and let them out.

surely though, evenif it was just faulty fitting, there shouldn't be swarms of them? We had a swarm of flies and it was a dead bird in the chimmney stack! It may be worth checking it out, just to be on the safe side

I shall send dh up on a ladder as soon as he gets back from work!

I am 99% sure you have something dead and rotting nearby. I moved to a new house about 3 months ago and it was always full of flies... and I don't mean 5 or 10... I mean swarms. It drove me nuts trying to figure out where they came from becuase the windows were all shut.

So, I went out, shutting all the inner doors tight. When I came home the lounge was like something out of a horror film. So, that narrowed it down to one room.

It was the only room with an opening (up the chimney. Called a sweep who took away the chipboard cover and found 3 dead birds. He fitted a bird guard on the chimney pot and the problem is cured totally.

So.... that many flies can only mean.... dead bodies of some creatures.

Yes, we also have had a massive fly influx over the Summer. If the windows are not left open, the flies seem to get worse. Even with the windows slightly open, we still manage to get flies. It is driving us insane - so I totally understand your frustration. If only I could shine some light.
We have checked our loft on several occasions. The first time, the loft was full of flies - so we planted a fly killer device which blasted them all with in 48 hours. Since then the loft has one or two flys buzzing round - but I can cope with that. We've checked for dead mice or rodents - but nothing.
I also have friends with barn conversions and they too seem to attract flies in their roof / velux windows.

I have the identical problem with Velux windows on a house in the country. I am told they are attracted to a yellow strip on the outside. It is only on the south side of the house upstairs. Eastern and northern facing Velux windows are clear

Sounds like you have cluster flies - we have the same problem in a house we moved in to a couple of years ago. Search Pest Expert on Amazon for some products you can use - I use the spray most often as it stays effective for quite a while after you have sprayed it on the windows (wear a mask when you spray it). You will have to get used to hoovering up the dead flies tho!! Good luck.

These are cluster flies. They come into attics in the Autumn and leave when the weather gets warmer in late Spring or early summer. Velux windows (at least older ones) have a design flaw which allows flies to get in even when they are closed. This happens mostly with Velux windows that get most of the sun during the day, as the flies look to stay warm. They then explore the obvious design gaps in the Velux window, that allow them enter the room. you can fix this problem as I did by opening the window and filling all the obvious gaps that you see. First though, start by fixing the padding in the window’s air-vent if it’s perished. I used strips of draught excluder for this. Next, get yourself some attic insulation from a hardware store and cram fill the gaps on the left and right vertical sides of the window. Now tackle the bigger job of filling the large gap at the top of the window. This I believe is the main entry point for the flies. Don’t fill it all with insulation. Here’s what I did. Half fill 5-6 plastic freezer bags along their length with insulation and tie off the ends. Stuff these across the back of the top of the window. Now, there’s still quite a gap to be filled but don’t use insulation as you’d probably only be creating a cosy place for the flies. So, do what I did; get yourself some empty Coca Cola cans and wrap them in aluminium foil. I can’t recall for certain now whether I used 330mm or 500mm cans but I think it was 5/6 330mm cans. These cans will tightly fit into the gap across the top of the window as they will collapse slightly as you push them home to tightly fit end-to-end. You will have to cut the last one to make it fit. Cut the can in two and get it to fit the gap remaining by cutting strips into one part of the cut can and then pushing it over the other part of the can. Tape it with adhesive or insulating tape and then wrap it in the aluminium foil before gently pushing it home to fill the last gap in the top part of the window. There should be no gaps between the cans. The finished job if done right should look acceptably decent. One last thing spray everything with fly killer as you go and wear a mask when doing so. If you do this as described, you should like me have no more flies getting into your room via your closed Velux window. You can then take a permanent rest from the constant killing and hoovering up of dead flies. Happy Days!

These are cluster flies. They leave a pheromone marker so if you have an invasion in the Autumn, chanmces are you'll suffer the same thing every Autumn.
They try to cluster (hybernate) in the small gap where the window sash meets the fixed frame. Its nothing to do with poor installation or bad smells, they just want to hybernate! Trouble is that the Velux window seals are not great and allow the flies inside the room. Once in they wake up with the warmth and fly around like crazy untill they drop dead with exaustion.
The only fix is to retro fit a good quality draught seal on the inside. done well it wont look too horrible and will provide a physical barrier to the flies!