Should I be putting this much weight in my screen porch

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michaelthomas

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Feb 10, 2006
286
I have been using my 10x12 screen porch as my winter wood shed as it is attached to the house and covered. The first year I put about a cord in it, last year about 2.5 cord and this year I am planning on putting 3.5 in it. I have mostly 2 year old Maple and Oak firewood. The floor structure is 2x10 joists resting on the foundation and 4x6 posts cemented below frost line. The floor is decking. I Stacked 2x6s up underneath the floor to act as a beam at the center of the joist span. I shimmed each joist so they are bearing weight on the beam. I also used bricks to support the span between the 4x6 posts. I stack the wood on pallets and will have 4 or 5 rows 18"wide, 11' long, and 6.5' high.
My question is: Am I overloading the structure? Also I live in Maine and we have significant snow load here, is adding 12,000# of wood and snow weight going to make this screen porch fall off my house or cause damage with the additional supports that i have places. Can I increase support to avoid damage?
 
I always like to think of things like this in 'peoples' weights. How many people would it take to worry about your porch collapsing? Compare that to your wood/snow.

When I put my stove on my slate hearth I tiptoed on as small as area as possible - I wasn't worried about the slate, so I shouldn't worry about the stove....

Standard disclaimers... blah blah
 
If it falls down get rid of the wood before you call the insurance company!
 
Our porches at the camp with a size and structure similar to yours sink from the weight of firewood. One of the rituals of May is getting the house jack out and leveling them out again. FWIW, its easier to stay up on it and jack a little than a lot. Relying on your insurance company doesn't seem like a good strategy.
 
2x10 joist is pretty heavy duty for a screen porch and extra support soulds like it can handle it
 
I agree with Smokinjay that the joists shouldn't be an issue. If anything, you will have the sinking posts like we do.
 
well 12000 is a bit heavy if the wood is seasoned right? hopefully your wood is dry therefore dramatically reducing the weight going on the porch! if your wood is dry i dont see a problem as it will get lighter as the winter goes
 
I got the wight per cord from the Chineysweep.com site and it said that Sugar Maple dried to 20% weighs 3700# per cord. The porch is filled and has a wood footprint of 11' long by 6.5' wide. The wood fills that entire space and is 6.5' tall stacked. I figure about 3.5 cord. The weight of the wood is close to 13000# and the footprint is 72 square feet and has about 180 # per square foot. I haven,t heard any cracking and there is definately pressure on the additional supports. I guess it is a matter of if the footings will hold up or not. We will see...
 
With 2x10s, that short of a span, and all the extra support, you should have no problems at all.
 
The floor joist aren't going anywhere. 2x10 is a big piece of lumber. Also, with one end of the floor structure bearing down on the footings I don't think that end is going anywhere. Now, how is this attached at the house? Is it the ledger board bolted/lagged to the house, or is it truely resting on the foundation? I've seen a few porch/deck collapses, and when the footings sink/move it can wrench the ledger board from the house.
 
I'd put 2 cord in there and leave the rest outside. I have 10 or 12 cord out in the weather, top coverd with plywood and/or rubber roofing material.

I have maybe a cord on my back porch, which is covered. It'd take me near a month to burn what's on the back porch. I know my wood outside dries nicely, even in the dead of winter, after it rains/snows. So what I do is, when it's decent weather, and the stuff out in the elements is rather dry, I re-stock the back porch. Works for me.
 
PICS!!!!!!
 
I disagree.

It is really two different design issues.
Your snow load is being transferred to the foundation. The snow is not impacting your floor, just your roof & foundation.

If a contractor did your porch, he probably designed for 100#/sft "live load" for your floor. You state (I agree with your calculations) that you're at 180#/sft "live load".

2"x10" joist size is just as important as spacing - 12", 16", or 24" on center AND the span (the length of the joist). You shortened the span by adding the beam, a good move.

Their are charts that cross reference all of those items. I'd get a hold of a chart and see what it says. Until then I wouldn't load my porch.

The other issue is - are your 4x6 foundation posts big enough to hold all of that. You are clearly off the chart (exceeding design) with your joists. Your foundation adds in all of those live loads, snow loads, and the weight of the structure, so you aren't exceeding that design nearly as bad as you are with your joists.

And to the ledger board - the other post has some good comments. I had a neighbor 2 doors away have his deck fall off because the ledger board wasn't properly attached. The neighbor and his father where on the deck when it fell off, and his 6 year old son was underneath. The son was ok long term, but did get a medevac ride. You can't rule out failure when you're on the porch. It might happen.
 
One side of the porch is directly resting on the foundation. However, unfortunalely it is not the side with the Ledger board. The ledger board is at the opposite end from the weight. The 4x6 posts are only about 12" exposed from the ground. I don't think I have to worry about them snapping as much as the settling into the ground issue that a post brought up. I feel less nervous after hearing from all of you.
 
1cord ok .... 2 cord ur pushing it but 3 cord ???? Think about it , is it really worth the headache of a destroyed porch???
 
If your deck is lag bolted to the house and the footings are in good soil and of proper size , you wont have any trouble with the deck .
I fill my deck with wood 14x14 x6' area 2x8 beams . 2x8 double header, and ledger board lagged to house .
If you add extra support in the center and the ground freezes you might have a problem with your deck heaving up from frost.
3.5 dry cord of oak weighs about 9500lbs this is at my dump trailer max weaight.
John
 
Redburn said:
1cord ok .... 2 cord ur pushing it but 3 cord ???? Think about it , is it really worth the headache of a destroyed porch???

hey hey, that's what I'm sayin', it'd be a bad, bad feeling to see the deck all smashed up and ripped to pieces, with the temps outside in the 20's, and snowin......

I say 2 cord max, I don't think a guy's gonna burn much more than a cord a month, maybe so depending, but look, you burn a cord, you replace it on a dry day, and you're good to go.....the other cord sittin there pretty and dry....
 
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