There are many roofs that are insulated with fiberglass which is very toxic. Fiberglass is not only toxic but can also be quite harmful to humans. It can cause breathing problems and itchy skin. Fiberglass contains adhesives that contain a carcinogen called formaldehyde which can release dangerous fumes. You can also look for the best house insulation via https://www.justritestore.com.au/home/insulation/
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The better option would be to use recycled cellulose fiber. This type of insulation is made from paper products, especially newspapers. It may be more expensive than fiberglass but it is certainly safer, and a great green alternative. It is usually manufactured in sheets but, for roofing insulation, it is sprayed on with compressed air.
This type of insulation is very fire-resistant. If you pick up a handful of it and put a blowtorch to it, it won't burst into flames. It will merely turn into black color and your hand will remain unscathed. Many sales representatives use this demonstration as proof.
If the rest of the house should catch fire, the cellulose fiber will slow down the spread of the fire. This could be critical in terms of time while waiting for the fire brigade. Another plus is that the fiber is vermin and rat repellent, so you can say goodbye to bugs, rats, and mice that scurry around in your roof.
Another effective and environmentally friendly insulation is soy. You can wear it, eat it and get biofuel from it, and now you can insulate your roof with it. It is manufactured with soybean oil. After being sprayed into all the roof areas it begins to expand.