Combining cellulose and fiberglass insulation can be effective, as it takes advantage of the strengths of both materials. Cellulose, made from recycled paper treated with fire retardants, provides excellent thermal and acoustic insulation. It's dense, reducing airflow and the movement of heat. Fiberglass, made from fine glass fibers, is lighter and less expensive but can settle over time, potentially reducing its effectiveness. When cellulose is placed over existing fiberglass insulation, it can help fill in gaps and improve the overall insulation barrier. However, it's crucial to ensure the existing fiberglass is dry and in good condition to prevent issues like mold growth. Furthermore, the additional weight of cellulose can compress the fiberglass underneath, slightly reducing its insulative properties, though the overall R-value (a measure of thermal resistance) of the insulation layer should still increase. Consulting with a professional is advisable to assess the specific conditions in your building and ensure the combination of materials won't lead to moisture problems or other issues.

Polypropylene, a type of plastic, is generally known for being odorless, which makes it highly suitable for various applications, including food storage containers and textiles. However, if polypropylene emits an odor, this might be due to manufacturing residues, additives used in the production process, or degradation of the material. Exposure to excessive heat or certain chemicals can cause polypropylene to degrade and potentially release a noticeable smell. Ensuring the material is clean and used within its temperature and chemical resistance ranges can help minimize any odors. If the odor persists, it may suggest the need to replace the item or contact the manufacturer for advice.

Duracoat Aerosol is a popular choice for firearms enthusiasts looking to apply a protective and aesthetic coating to their guns. The amount of coverage you can achieve with a single can of Duracoat Aerosol largely depends on the size of the firearms and the manner in which it's applied. Generally, a 12 oz can is expected to coat 2-4 handguns or a single rifle or shotgun, assuming a thorough but conservative application. Factors such as the complexity of the firearm's surface and the desired thickness of the coat will influence the exact coverage. It's advisable to plan your project carefully, ensuring you have enough material to cover your needs, and possibly a bit extra for touch-ups or mistakes.