200mm knauf insulation between attic rafters

[Keitai]

Is this good insulation amount and will it work? Is it easy to install and safe on my lungs?

 

[freddiemercurystwin]

Depends how long you plan to live?

 

[GhostIntMachine]

Is this good insulation amount and will it work? Is it easy to install and safe on my lungs?

i presume you mean the brownish stuff. Whilst it's nicer to install than the old fibreglass or mineral wool insulation (you won't itch as much - or break out into a nasty little rash), you still need to wear a P3 mask when installing it as the dust/fibres off it can get on your chest, especially in confined spaces. Dust/loose fibre release can be minimised by cutting it on a piece of board, using an insulation knife:

And despite looking like one, it ISN'T a bread knife (it cuts faster and cleaner with less dust/fibre release than a bread knife)

 

[jj4091]

The obvious question would be how does it differ from a bread knife.

If it walks like a duck and quacks like a duck

 

[GhostIntMachine]

The obvious question would be how does it differ from a bread knife.

If it walks like a duck and quacks like a duck

Oddly enough it isn't as sharp... But I found that it cuts quicker, cleaner (i.e. leaves a clean edge - important if you are after air tightness or the edge is seen) and with less dust than any bread knife I've used. And there have been a few - seemingly one every job or two for quite a few years. It also creates less dust, possibly because it cuts more cleanly? I had the firm buy it for me back in 2017 when we were installing a couple of thousand square feet of some gawdawful German recycled wood fibre soundproofing (in a new library ceiling - above a suspended oak grid), found it could do PIR and mineral wool as well - so I haven't used a bread knife since. Because you can draw the blade across the palm of your hand without breaking the skin, it's arguably less of an offensive weapon than a bread knife, should you ever be stopped dragging a tool box off a job at 3am in the middle of Leeds (don't ask...). They also got a Bahco wavy edge saw at the same time as well, because we didn't know which would work faster/better:



Surprisingly (to me), the saw didn't cut the sound insulation as fast as the Stubai insulation knife and was it was more difficult to keep it cutting in a straight. vertical line. I actually haven't tried it on PIR or Rockwool/Earthwool, so I don't know how well it cuts them, but being bigger than the knife (about 26 to 27in overall) the saw won't fit inside any standard toolbox unless packed diagonally (a PIA), which is another disadvantage to my mind

 

[Keitai]

Ok thxs, think I'll pass on this job. No point breathing that in and doing a crsppy job she just doesn't wanna do herself