# Garage storage in rafters?



## kirwinjd (Dec 31, 2012)

Any way of determining how much weight the rafters above a garage can hold? I put several sheets of 1/2" plywood up there and 
as I shove more stuff up there I'm becoming increasingly concerned that I'm putting too much weight on the joists. I'm trying to move the heavier stuff towards the load bearing walls but I know either way, the garage rafters weren't made for a storage area.

Thank you


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## joecaption (Nov 30, 2011)

That's the spans, spacing and size of the joist?


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## MJ Force (Jan 1, 2013)

Are these rafters part of a roof truss system? Are these engineered truss's*. 
Typically a roof truss system is designed to accept the weight of a finished ceiling. However the material would be evenly distributed. Loading material unevenly could cause deflection to the roof or worse, failure of a joint. 
If you call a Roof Truss Builder and describe the specs and design they may suggest some ways which you could "beef them up". There are several design to pitched roof trusses ie; web, king post etc.


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## kirwinjd (Dec 31, 2012)

joecaption said:


> That's the spans, spacing and size of the joist?


Thanks for the reply.
Joists are 2x4, mostly spaced at 24", a few spaced at 14". Dimensions are 20'x25'. Looks like all the joists were lengthened with a web nail plate and a short block on top. Definitely a pre made truss design. House is only a 12 year old track home


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## kirwinjd (Dec 31, 2012)

MJ Force said:


> Are these rafters part of a roof truss system? Are these engineered truss's*.
> Typically a roof truss system is designed to accept the weight of a finished ceiling. However the material would be evenly distributed. Loading material unevenly could cause deflection to the roof or worse, failure of a joint.
> If you call a Roof Truss Builder and describe the specs and design they may suggest some ways which you could "beef them up". There are several design to pitched roof trusses ie; web, king post etc.


Great thanks for the info. It's definitely a pre engineered, per built truss system. My house is one of about 200 of the same model built in the neighborhood.
My other reply describes the construction of the garage. 

Question: if I was to exceed the design capacity, would I get any warning of an imminent collapse? Since the house and garage are joined together would that
Cause any damage to the house itself? My main concern is that I'm about to reload the garage rafters with a bunch of Christmas decorations, lights, ornaments etc.


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## Missouri Bound (Apr 9, 2011)

kirwinjd said:


> I know either way, the garage rafters weren't made for a storage area.
> 
> Thank you


 ...but you will do it anyway? :no:


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## GBrackins (Apr 26, 2012)

got some photos you could post?


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## Hammer450R (Aug 17, 2012)

They are not designed to store anything on.


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## kirwinjd (Dec 31, 2012)

I'm going to hire a structural engineer to see if I can add some support to the trusses. I need as much storage area as possible and even though the trusses weren't designed for storage, it seems like everyone in the neighborhood does it anyway. 
Thanks for the replys


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## AndyGump (Sep 26, 2010)

I would love to see a picture of these things.

Andy.


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## Duckweather (Mar 26, 2012)

Usually with engineered anything the warning you will get is a very loud crack about 4/5ths of a second before you hear the sound of a car being squashed. The proverbial straw and camel syndrome.


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## Daniel Holzman (Mar 10, 2009)

A bit of terminology. You apparently have manufactured trusses. Assuming this is the case, you do not have rafters, and you do not have joists. The truss is a single unit, each individual piece is generally referred to as a truss element, and the specific parts of the truss have common names, for example the top pieces are often referred to as chords.

In any case, residential trusses are normally designed to be loaded at the connection points, called nodes. You will be loading between the connection points. It is certainly possible to analyze the effect of loading between the nodes, but this is not a simple analysis, and it is generally not a DIY calculation. In some cases, the manufacturer of the truss will tell you the maximum allowable uniform loading on the bottom chords of the truss, or they may simply tell you that your truss is not designed for any loading.

A few pictures would really help, as you may not have actual trusses.


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## Fix'n it (Mar 12, 2012)

i did this with great success. but i will not comment without seeing pics.


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## MarkSindone (Feb 17, 2014)

Photos would really help us unerstand the storage situation a little bit better. Even the placing and material would make a big difference about how things are going to hold up over time too. Hope you can get some soon to share with us then we can really give you better advice on your storage issue.


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## curtd (Oct 25, 2013)

I wouldn't store plywood up there. Too heavy. Lean up against wall


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## MarkSindone (Feb 17, 2014)

Photos would really help us unerstand the storage situation a little bit better. Even the placing and material would make a big difference about how things are going to hold up over time too. Hope you can get some soon to share with us then we can really give you better advice on your storage issue.


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## jogr (Jul 24, 2007)

Since the OP posted this in January of 2013 he likely won't answer. He's probably buried under his collapsed garage.


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## ron45 (Feb 25, 2014)

A lot of helpful info, such as.....

Living room floors L/360 & 40 psf
Bedrooms and habitable attic floors L/360 & 30 psf
Attic floors with limited storage L/240 & 10 psf.

http://bct.eco.umass.edu/publications/by-title/understanding-loads-and-using-span-tables/

Here's a calculator
http://www.awc.org/calculators/span/calc/timbercalcstyle.asp


.....


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