Woman in underwear in own home

YABU. Presumably, the contractor was embarrassed and assumed that you would be embarrassed too. They are letting you that he'll be there again so you can close the curtains.

If you choose to walk about in your underwear in full view of the contractor after they've said this then you will look like the perv, not them.

What a lot of fuss over nothing. You're unreasonable to be 'raging' and yes, I think you're overreacting.

The contractor was wrong to gossip to the neighbour that he'd seen you in your undies.

The neighbour was likely purveying a warning, in an awkward way, that the contractor will be back and you may not want him seeing you partially undressed. He could have worded it better but probably only concerned for you.

There is no need to hide. If you still haven't had time to sort out window coverings then just send off for a roll of opaque or reflective window cling from Amazon and have it in place for the duration of the guttering install. You literally wet the window and press it on. Peels right off again.

The thing that puzzles me the most is, if your flat is first floor, and the contractor was working on a house to the side of yours, how he saw in your first floor window? I can't visualise how he saw you if you weren't near the window.

Maybe it was just a heads up in case you might be bothered by someone seeing you like that.

Oh the Mumsnet double standards. Wasn’t that long ago a poster was talking about her DH walking around in his pants and everyone was saying how vile he was and what a pervert he was and how gross he was.

Is this satire?

Maybe it's just because the roofer is male, the neighbour is male, and he bumped into her husband before he saw her? Or maybe he felt awkward telling her face to face? I imagine he's only relaying it as a warning, so that if OP might feel violated by being unexpectedly glimpsed in her pants at home (I know I would) she can take steps to avoid it happening?

I'm with you, OP - the 'chain of men' thing is the key here - it's misogyny pure and simple - reporting it to your husband as they probably think he needs to keep you under better control or maybe give you a slap for being such a cock tease. Many men are arseholes.

I had the voice of George Formby narrate that 🤣

I spend every morning in my bra and pants, which now unfortunately my DD issues a health warning about when her friends drop by as I have made an accidental
appearance before.

I wouldn’t take any notice OP

I read this as, BTW you do know he can see in, don’t you? If you care take action.

I now have an emergency dressing gown 😄

I think he was passing the info on because he’ll be doing the guttering and doesn’t want to see you in your pants.

Who are all these Peeping Tom supporters who voted YABU?

When was the last you felt the need to mention your neighbour’s underwear when you spoke to them?

That is very sad of them. Probably the most exciting thing to happen to them for ages. I’d watch out for “helpful” neighbours if I were you. IME they can be quite invasive.

I would set a boundary with the neighbour (even say I’d rather their guttering guy doesn’t do ours) and tell your DH to too. None of their business what you do in your own house.

Letting you know the neighbour has a contractor who is a perv. Maybe not the best way but better you know than not.

It's just a heads up, to ensure you are aware you might be seen.
I'd wager most women would prefer that workmen did not see them in their knickers.
The workman might have asked the neighbour to warn you, and to avoid being accused of something, rather than gossiping.
You are being ridiculously unreasonable.

I don’t understand the strength of your reaction.

many years ago I worked in a pub . My neighbour opposite told my boss that I walked around in my bedroom in my underwear. I probably did while I was getting ready but I never stood in the window as it was a large bay!

There is a block of flats opposite my office and we do see people in their underwear or completely naked very often. We do puzzle over whether people are exhibitionists or genuinely unaware. They must be able to see into our office very clearly so surely they realise that we can see them.

Of course he’s being sexist. I bet you anything he wouldn’t tell your husband he could see him in his underwear because he would think it’s fine for men to go round in their pants but he’s pearl clutching about a woman doing the same.

I go round in my underwear in my own house when it’s boiling hot. Like you it’s not a thong and a few bits of string, as I wear shorts style knickers and a sports bra. I would be raging too if a neighbour told my husband about it as if I was too dim to work out I could theoretically be seen. I’d be peed off partly because it’s none of their business and if a woman was talking about this kind of non-news she’d be called a gossip and a curtain twitcher; partly because it feels like they think they need to bring you in line to show some decorum; and partly because you’re an adult and don’t need to be given the heads up about the correct clothing to wear in your own house.

Id appreciate being told that a random man could see me into my home if I didn't realise. There were more tactful ways of delivering the information "Oh BTW, when he's working he can see right into yours" would have done.
But I think you're making a few assumptions here that paint this in the worst possible light.
That the guy was leering.
That he discussed you with your neighbour (rather than both men simply noticing).
That he deliberately told your husband so he could tell you off (rather than just because it was him he was talking to).
That they were telling you you couldn't wear what you liked (rather than telling you you could be seen).
Your assumptions could be correct, but there's enough doubt not to go round 'raging'.
You now know the guy can see in. Entirely up to you what you do with that information.

I don’t think he complained or said he didn’t like it, but is letting you know incase you didn’t realise you could be seen.
you now know you can be seen, so up to you to decide what to do with it

You have curtains or blinds now? I’d be kind of weirded by the guy’s comment to your neighbour. But I think your neighbour just told your husband so he could let you know that, until you could get window treatments, you should be aware how easy it was to see you, and consider whether you’d what to adjust your wardrobe or not.

I remember watching a programme at school
about how one should shut their curtains at night/when getting changed as stalkers can see it as performance. Maybe he was just giving you the heads up. One of my neighbours used to walk around naked & I assumed he didn’t realise I could see because one day our eyes met & I never saw him naked again 😆

Just a heads up really isn't it?
He's giving you warning that the contractor will be able to see in and not to be naked.

It would be much worse to be surprised by a plumber at the window while in the nud.

Nice ageism there!