Navlgazer t1_je12m6p wrote on March 28, 2023 at 5:24 PM

Reply to comment by so-very-very-tired in Can I reframe one bay of roof trusses to create a more comfortable opening between posts? by pearapplecherry

The weight of a person isn’t any different that all the junk people store in Attics .

so-very-very-tired t1_je18n3h wrote on March 28, 2023 at 6:01 PM

It's not about the weight of an individual...it's what the truss system is rated for in terms of live loads.

They're usually not rated for live loads above/beyond storing your xmas decorations and maybe some boxes of old clothes and the like.

A residential floor it typically rated for 40lb live load. I believe (but don't quote me) roof truss floors are only required to be rated for 20lb live load if only used as attic storage space. And builders tend to use roof trusses for being cheaper to build/install and rarely over-build.

Granted, you can certainly get trusses that are rated much higher, and perhaps that was done here.

For example, there are things called 'attic trusses' which are designed to usually handle 30lb live loads on the floor. The other main advantage is that they are designe to leave a larger open space in the middle (vs your standard roof trusses which use all of the diagonal members as in the OPs photo). These are great when used but they're rarely used by default simple due to them costing a lot more.

pearapplecherry OP t1_je3dk5c wrote on March 29, 2023 at 2:50 AM

Great point - I don't remember the exact load calcs, but we've had movers and all sorts of awkward heavy heirlooms up there in the past with no real issue, it really is just holiday junk at this point. I respect the abundance of caution though.

And to clarify no it's not an active living space; my dad set it up as a covid quarantine (which fortunately was never necessary) and decided to stick it in the corner and save space for more the aforementioned junk.