Eaay to handle loft insulation

I think I used that Knauf stuff from Wickes when I did mine, it's perfectly fine to handle. If it is dusty in there I'd invest in a decent fp3 mask -Elipse £30 from Wickes

Sheep's wool in our loft.. Seems great. Lovely to use!

There are plenty of 'modern' fibre insulations that don't cause the same level of itch-hell as the old stuff. Having said that, wear some old clothes, gloves and a FFP3 mask as mentioned above.

I’ve been looking at this  https://chimneysheep.co.uk/collections/wool-insulation

Here you go, Sisalwool.

https://sisaltech.com/

Breathable, easy to work with, made in the Bush science park just outside Edinburgh so you can just rent a van and go pick it up. In the middle of refitting our loft with it.

Rock/mineral wool was fine when I did ours, just make sure you have gloves and a mask and some old clothes. If you do get any on you (always the wrists) rinse it with cold water.

Good masks are brilliant, I got a Draeger half face with replaceable filters years ago, can get a bit sweaty but keeps everything out.

I wasn't even aware glass wool was still a thing, horrible stuff!

The Knauff rockwool stuff makes me itch but I have sensitive skin. It is *nowhere near* as bad as glass mineral wool.

The white Diall stuff is great from a non-itch perspective but it is idiotically expensive. I've only used it on small areas i touch regularly, e.g. around the loft hatch.

I used the diall stuff in the eaves for similar reasons to your self.

I didn't need many rolls . My eaves are not big. It made a huge difference.

The rest got the 3 for 2 cheap cheap 200mm roll stuff.

My experiences, all in 100mm/120mm, rolls or panels:
Fibre glass - the worst IME. Even with a mask and glasses the lungs and eyes suffer, everything else itches and it won't shower off easily. Floppy and and even if it stays in place initially sags and compacts in the long term.
Rockwool. Better, it still irritates but less so. Cuts with a box cutter. A bit floppy but springy enough
Wood fibre: the dust is phenomenal, but it irritates less than the above. Requires a special saw to cut, stinks. Quite rigid so requires accurate cutting and springy enough to hold in place
Hemp, cotton and lin mix:  dusty but less of it and easier on the eyes than any of the above. Very hard and time consuming to cut with good scisors in several passes. Stinks. Springy and stays in place well
Polyester wool: very pleasant to work with, yes you did read that right, very pleasant to work with. Cuts to size easily. Springy and stays in place well
Multi layer insulation with 27 layers or more of aluminium foil, polyester and some foam stuff is about the equvalent of 100mm of the above. It's easy to use but requires an effort to seal the edges and joins to make it effective.
In terms of performance they all work well against the cold but the fibre glass and polyester wool are disappointing against the heat. The multi layer stuff gets bad press but IME works well. The wood fibre and Cotton/lin/hemp have a higher thermal inertia (they're heavier) and definitely protect better from the Summer heat.

Edit: rodents, they made homes in the glass wool which I had to replace but are less enthusiastic about wood fiber or polyester wool (I assume that's what people are calling "white Diall"). I don't know what they think of the cotton/lin/hemp yet.

The stuff I got years ago from B&Q was apparently made from recycled bottles. It was absolutely fine to work work with.

I still wore long sleeves, gloves & a face mask as there was a lot of dust & old insulation which I think was more traditional 'itchy' stuff already in the loft.

These two are popular in these parts, no idea if you can get them local to you. Wood fibre under the tiles (with no membrane before anyone asks) then cotton/lin /hemp. The last layer I've yet to decide, probably polyurethane boards (similar to Celotex) but I'm hesitating as it's toxic if there's a fire.

The recyled bottle stuff is the polyester wool (Diall), Stumpy. I think I've already posted a pic of that used to insulate under the floor.

+1 on cotton, hemp or wool.
You can get woodfibre in the UK as well.

I did our loft out in this stuff  https://thermafleece.com/product/thermafleece-cosywool-sheep-s-wool-roll

Lovely to handle, can tear by hand or cut with bread knife for more accurate edges if needed, plus treated against moths, fire, etc.

There is a great place in Stirling called Insulation Merchant that does a great range (but not Sisalwool) including all the wood fibre/hemp options, along with all the breathable membranes and posh tapes if you want to go that route. I'm not having the most fun with it, but it will be nice when it's done. They are also very helpful and gave me some great advice on how to deal with our pitched roof to flat roof transition.

Nice and easy to handle is great for new stuff going in but what to do with the old crap? Think ours needs doing as it looks a mess of new, old and very old (and some sofa cushions!). Removing everything that is there looks a large horrible job.

Removing the old stuff was a large, horrible job. I don't ever want to have to do it again. If we move, it's into a modern ultra insulation new build 😂

It took weeks, we can only take the van to the tip once per week, so had to do it quite spread out. Full PPE rolling it up into bin bags, trying not to spread the dust. Dead mice n all. Fill the van, clean down, wait til next week then repeat. Underneath the 'back to the dawn of insulation' stuff we chucked out I found a cm or so of grim black dust filling the lath and plaster. Borrowed a big industrial hoover to clean it up. One joist gap was about 25kg of dust, times 25 gaps. I did check, the tip knew what we were bringing and cleared it all.

Then the higher than expected £1700 from the electricians to raise the cables enough to get the new insulation underneath (they did stick a few new ones in for future solar too)

I set 5 days aside to lay the membrane and fit the new stuff. At the end of those days I had tendonitis and about 30% done. So now it's fit it in when I can.

I do wonder if the time added to my life by living in a warmer less mouldy house will be offset by the days spent cleaning the old stuff out 🤷 Who knows eh.

Do you really need to remove the old stuff?

My loft is decked out with what looks like typical yellowish glass fibre nasty stuff, I was just planning on rolling out some newer easier to handle stuff straight on top of it?

I had the same issue as Pigyn, the electrics needed raising and some plumbing modifying. I prefered spending a few days making a clean working environment than try to do the work in a cloud of dust wearing a mask and misted up goggles.

Is that wood fibre stuff more insulating for a given depth than the usual rockwool/fibre roll?

I want to board my "cold" loft but don't want to lose too much height if possible.

Bottom chords of the trusses are only 38x75 so wondering if that will be strong enough despite 1995 build.

I think new regs about loft strength were 1996.

Do you really need to remove the old stuff?

From what I've seen a lot of ours is falling apart. Only way to cover an area with it is to push it down which I'd have thought reduces the insulation value.
Quick search seems to suggest you can have it removed by suction. Doing that is tempting. Moving around in our loft space is not that easy though as it's the eaves around a room. Ideally I'd add a crawl way covered in easy to move insulation though does that then add in a cold bridge.

Thanks all for the thoughts. I'll give Sisaltech a call as they were very helpful during my failed attempts to do anything to the flat roof section. I remain a bit unsure about the moth issues with a lot of wool based stuff, appreciate most of it is treated in some way but you don't have to go too far into the various heritage building groups to find various infestations. So maybe the Diall plastic stuff is the way to go (if it's good enough for trail_rat that's a good enough endorsement for me).

Thankfully it should be a fairly clean and easy job other than the exceptionally tight space. Certainly don't have the hours in my week to be taking days to remove and clean out old stuff so I'd be getting someone in if it was that long!