Midge mesh window Scotland: standard mesh is not the same

The window is open on a still evening, on the west coast or in the Highlands, and the insects in the room are not houseflies. A midge mesh window in Scotland is a finer specification than the sheet sold for wasps and bluebottles in most of the UK. Two British sellers do not even agree on the thread count, and the tesa Insect Stop listings in our comparison do not print a grade at all.

You can still keep ordinary flies out with a standard sheet. You should not tell yourself that the same sheet has stopped Culicoides because the packet says insect. The Products Compared editorial team used amazon.co.uk listings, Streme's mesh guide, Scottish Shutters' midge-mesh guide, and the Smidge forecast page. We did not laboratory-test hole size or airflow. A qualifying purchase can earn us a commission at no extra cost to you.

In short

Do not assume a standard fly screen is a midge screen. Streme describes midge mesh as 30 by 20 and says 20 by 20 or 18 by 16 will not keep midges out. Scottish Shutters sells a 20 by 20 mesh it says stops them. None of the tesa sheets here states a midge grade.

Midges are smaller than houseflies

Scottish Shutters' guide names the Highland midge as Culicoides impunctatus and gives a wingspan of about 1.4 mm. That figure belongs to their page. It is not a hole size printed on tesa tape, and it is not a thread count. A hole that stops a housefly can still pass an insect of that size. If you hold a standard sheet up to the light and can see a clear grid, you are looking at holes, not at a guarantee.

Streme's which-mesh guide treats standard mesh as the cloth for most of the UK, and midge mesh as the tighter cloth. Its help page separates the two and calls out Scotland and Northern Ireland. A sheet that is fine in a Surrey garden in June can be the wrong promise in Argyll or on Skye.

A week in a west-coast let, with a sheet bought because the title said fly screen, is not a trial of midge mesh. One saved review on listing B00569J8CQ, from west-coast glamping, reported that midges did not stay. Other reviews say gnats passed. A quiet stay can mean a low forecast. It cannot become a grade the listing never printed.

Two UK sellers, two mesh claims

Streme says midge mesh is 30 by 20, and that 20 by 20 or 18 by 16 will not keep midges out. Scottish Shutters sells a 20 by 20 mesh and says that cloth stops Highland midges. Both sentences are on those sellers' own pages. They cannot be averaged into one comforting count. One firm is telling you the coarser count fails. The other is selling that coarser count as the solution.

If a fitter, a glazing firm, or a product title says only midge mesh, ask which count they mean, and ask them to put it in writing on the quote. A 20 by 20 that Streme rejects is a different object from a 20 by 20 that Scottish Shutters stands behind, because the yarn thickness and the hole can differ even when the count looks identical. Thread count is a shorthand. It is not, by itself, the hole in millimetres.

Scottish Shutters also claims about 40 percent less airflow through its midge mesh. That is their claim about their cloth. A tighter weave costs you breeze, and the figure is not a lab result for any tesa sheet. There is no British standard, in the sources used here, that collapses the two claims into one legal mesh.

What the tesa listings do not say

Our tesa fly screen comparison covers twelve amazon.co.uk listings. None of them prints a mesh grade. Standard, Comfort, and Open/Close are sold as insect screens you trim or roll, not as Highland midge mesh. The top pick for a tall French window is the anthracite Comfort sheet, 120 cm by 240 cm, at £9.51, with 4.4 out of 5 from 17,369 reviews. That score is about a tall sheet people can peel back. It is not a midge test. Cut to size is not stated on that listing.

The white 130 cm by 150 cm Standard sheet at £7.20 is the best value in the set for one ordinary window, if the sheet is larger than the frame. Open/Close Premium at £23.99 rolls aside so you can use the handle. If you needed 30 by 20, or a 20 by 20 that a Scottish fitter has specified in writing, none of these prices buys that sentence.

A review is not a specification. The west-coast glamping note on B00569J8CQ is one stay, and other reviews say gnats passed. Gnats are not automatically Culicoides impunctatus. The 4.4 from 17,369 reviews measures tape and coverage, not a 1.4 mm wingspan.

Measure the frame in more than one place and buy larger than the largest reading. The buying guide is that order. An outward-opening casement can still be blocked by a tight sheet. That limit is on fly screens for outward-opening windows.

Forecasts and still evenings

Smidge publishes a midge forecast as a daily map on a scale of 1 to 100. It tells you where activity is expected. It does not test a screen, and it does not convert a standard sheet into midge mesh. That is why one quiet glamping night cannot grade a product.

Wind does not shrink the holes. People notice midges most on still evenings, when the sash is open and the room air is not moving. A gale is a poor ventilation plan, and insects can still pass on the lee side of a coarse weave.

Finer mesh passes less air. Scottish Shutters' 40 percent claim is their figure for their cloth, not a measurement of a tesa sheet. A tight screen with no other vent will feel closer, which is the trade-off if the alternative is midges in the bed. Scottish Shutters treats the Highland midge as seasonal. This page will not invent the months. Check the Smidge map for the week you are there.

When a standard sheet is the wrong promise

Buy a tesa sheet when you want a no-drill insect screen for houseflies and similar larger insects, the frame is clean, and the listing size covers the opening. The how to fit page is the stick-and-trim order for sheets that are meant to be cut. Do not start that job in the belief that Standard mesh has become midge mesh because the postcode is Scottish.

Buy a stated midge mesh when the forecast, the location, or last summer tells you that ordinary cloth failed. Get the count in writing: 30 by 20 if you are following Streme's warning, or the seller's own 20 by 20 if you are following Scottish Shutters and you accept their airflow claim as theirs. A made-to-measure frame can carry that cloth. A tesa packet in this set cannot, because the grade is absent. Paying £9.51 or £23.99 does not fill in a blank specification.

If midges are already in the room, check the tape line before you blame the weave. A gap at the corner admits insects a fine cloth would have stopped. If the perimeter is sealed and they still pass the grid, the grade is wrong, and another reel of the same sheet repeats the error.

These listings are standard insect mesh unless a listing says otherwise, and none in this set does. Use them for flies. For a midge mesh window in Scotland, ask for the count the seller will stand behind, and do not average two rivals into one comforting number.