Plague of flies

Mon 29 Nov 2021, 13:35 (last edited on Mon 29 Nov 2021, 13:47)

Phil, it's the other way around. Floor joists support the floor, ceiling joists support the ceiling (of course floor joists on upstairs floors do both). The timbers that support the roof itself are the rafters. This is from a UK site. As far as I can tell the terminology is universal in English-speaking countries.

Modern houses tend to use roof trusses which combine the rafters, ceiling joists and other wooden web ties in pre-assembled frames. They use somewhat smaller section wood and rely for the webbing to give them strength. Something of an expensive job to reinforce if you ever perform a loft conversion, but that's a different matter.

Sat 27 Nov 2021, 14:09

Malcolm, here in GB we call the roof supporting timbers the "joists" and the ceiling supporting timbers the "rafters". My expanding spray foam went between the joists. I was invited by the contractor to watch it being done - seemed like a magic process!

A single spray sweep into each gap expanded into a 4 inch deep foam panel. It is a breathable product so that there is no risk of condensation. 

If anyone is interested, I can provide the name of the contractor that I used (message me).

Fri 26 Nov 2021, 18:18

We had exactly this on a south-facing double-glazed skylight last weekend - swift bout of hoovering (disposed of outside) and a Rentokil spray did the trick. First time in 12 years in the property. Hopefully the last.

Fri 26 Nov 2021, 18:10

Phil, do you mean between the joists on the loft floor? Or sprayed onto the inside of the roof to make an insulated and warm unnofficial but useably warm loft? Be lovely to construct that highly modelled railway scenario one has ever coveted.

I've always thought the best place for loft insulation was up on the underside of the actual roof itselt thus freeing up a damp-free loft space. If it could be done with Kapok in the early Colonial style house from the 1700s why not do it now!? I was born in a countryside house with kapok wall lining underneath pannelled wood whalls and ceilings, built in ca 1740 something. The main body was limestone rock, beeing within visual distance of a quarry. It was a very modern house in its time. The well was in the 12 foot deep basement thus saving trips out into yard in -29 degree galeforce winds and blown ice conditions.

Fri 26 Nov 2021, 13:46

I had experience of fly infestation a few years ago. Very small black flies which descended from my loft space via the hatch. They swarmed over my landing window in late November and I had to regularly open the window wide and sweep them out with a hand-brush. Environmental Health came out and had a look. The bloke said, "Sorry mate, once you've got 'em, you've got 'em forever!" Apparently they return every year once they have got an established site. They come in under the tiles and breed on the joists. Then they are drawn to your living space by the warmth of your central heating.

I found a solution and it is not cheap but it has greatly reduced my energy bills!

In 2015 I had all the joist gaps sprayed with expanding foam insulation. Cost me £6.5K but I think it's money well spent. The loft space is now exactly the same temperature as the rest of the house and the bills have reduced by 30%.

And....not a single little black fly in sight!  

Fri 26 Nov 2021, 11:04 (last edited on Fri 26 Nov 2021, 11:05)

Presumably I missed the one of frogs and we have boils, locusts and worse to come...

Fri 26 Nov 2021, 10:28

Almost exactly a year ago Jean asked for help about a fly infestation. 

It might just be a late-November thing, but in case you think they are cluster flies the link is here: https://www.charlbury.info/forum/7289#40377

Thu 25 Nov 2021, 20:35

Is anyone else suffering from lazy, annoying flies? They seem to be coming out of every hole and hiding-place and just sitting around with little concern for their own welfare.