I am replacing the ceiling in my flat with some soundproofing materials and since these are heavier than usual materials used I want to check if the new materials would pose a problem. The room I want to apply this to is 3.3x4 metres. Joists Height: 22.2 cm / 8.85 inch; Width: 5 cm / 2 inch; Length: 330 cm / 130 inch 30 cm spacing between these; 13-14 joists What I want to know is how I can calculate the maximum load that the ceiling could hold. Any ideas?
Yes, so they are the joists between my ceiling and my upstairs neighbour's floor but soundproofing materials are heavier than usual building materials so would like to know how to deduce the load the ceiling would handle
Those joists at 400 crs would be safe up to 4.79m span for normal floors even if they're the weakest structural grade. Unless you are adding huge weights, you'll be fine. If you are adding such weights then you need a proper SE check.
Even if you had the highest standard dead load acting on the joists and your neighbours doubled the the standard floor loading the joists would still easily pass allowable deflection and strength requirements for standard house construction. Weights of what you are taking down and what you are putting back up would be more useful then a calc on the extra deflection of the joists could be made (there will be no problem with the strength). As for deducing what load the ceiling could take thats easy enough if you have a understanding of structural timber design and what parameters you need to works to