did I cantilever too much?

[deercamp14x28]

Hi all.  I have a 14x28 cabin I built using the Little House plans from this site a couple of years ago.  I finally started on my deck a couple of weekends ago.  I laid the posts in concrete several weekends ago and I framed the deck last weekend.  When I cut my joists, I thought, "what the heck...I'll add a couple of inches".  I generally overbuild so I thought I'd be well within spec.  Here are the stats...

The posts are pressure treated 4x4's 5 feet apart.  The beam is doubled-up pressure treated 2x8's.  All joists are pressure treated 2x8's.  The beam is exactly 6' away from the deck.  The joists are are 7'8".  So this means that there is a cantilever of 1'8".  The deck boards (going on Saturday) will be pressure treated southern pine decking boards (5/4x6).  

Now once I had the entire deck framed the cantilever just looked a little long.  I know it's within spec for a deck - but am I going to be in trouble if I put a porch roof on this deck?  I know it's plenty strong, but I guess I worry about the part of the deck attached to the cabin rising if there's too much weight out on top of the cantilever.

Here's a pic of the deck thus far...
http://www.michaelsledge.com/deck/pages/IMG_0568.html

The rest of the pics of the deck...
http://www.michaelsledge.com/deck/index.html

Am I crazy or do I have real reason to worry?

[PEG688]

Deercamp  I couldn't open the pictures but if I where doing what you might do could you run new post at the outer corner past the cant to put the roof purlin / beams on ??  on new post bases?   Might look clubby and maybe I'm not following your plan for how the futrure roof will be held up   On post down onto the deck top???  Avoid hinge points go to direct bearing ,  That is assuming it 's a gable roof well even a shed roof  would be the same .  or replace the existing 4x4 post with maybe 6x6 and extend them up to hold the roof support , savie ??   I'm not tecie so I can't draw it up on the puter . I see it but need a 2x8 to draw it up on    So if you though you'd put post at the cant corner to support the roof I'd rethink .  Hope this helps , HTBH ;)PEG

[deercamp14x28]

Oh, sorry.  Those weren't the correct addresses.  I've edited my post to reflect the correct addresses.

My plan (flexible) is to put some 4" diameter cedar trees on the deck surface, put a beam across the top of them, and then hang my rafters for the porch roof on that beam.  It will be a shed roof - you can see the ledger the rafters will be connected to in some of the other deck pictures...

[PEG688]

  Get longer / taller trees    How quick do you want it if they are growing might take some time .  Miracle grow    HTBH  ;)PEG

[deercamp14x28]

Not 4" tall - 4" diameter!  I've got some trees identified - I just haven't cut them down yet.  If they don't work out I'll just use some pressure treated 4x4 posts which would probably be easier - just more boring.  

So is my cantilever too long for something like what I want to do?  The roofing material will be metal roofing similar to what I have on the cabin - I won't be putting plywood down on the rafters however.

[PEG688]

 How about dbl the rim joist and first one in and solid block under the cedar post, both ends and at any intermedate , post  . No plwood only metal, keep it lightweight , although the plwood 1/2 max would provide wind shere to the roof the metal wouldn't .  . Snow load  Not sure where the cabin is   Get a good tag top and bottom with something long lag bolt / strap .   A metal strap in a knotch in the post top and bottom with a tru bolt or two , something to prevent pivot points ..I'm thinking your not having to meet code of course.   Some combo of the above will keep her up.  Good luck , HTBH  ;)PEG

[Jens]

as far as I was told, the UBC states that you can cantilever 3ft if yo have 9ft of joist on the other end, and that was with a load bearing wall on the cantilevered part.  In other words, 30%.   1'8" is less than 30% of 6', so I'd say you are probably good to go.

[rwalter]

If my memory is correct normally for residential structures you should not cantilever more than 24" away from the beam or support wall. So your joists are 92" and your cantilever is no more than 20", therefore you should be fine. I vaguely remember something like 1/3- 1/4 of the joist length is allowable.

[PEG688]

without the roof load on the cant yes    With a roof on the cant , not knowing potental loads   no way    Look at the situation only the decking and hangers at the house end no real counter weight , how will the rafters be  hung at the house end   a lot of weight , the heavy end of snow the run off if it freezes at the eave in the evening , which it will and more snow , and a early melt the next late AM  earlyPM and a lot of load is place out at the end .  Hey I'm not a engineer justa 49 year old carpenter , what do I know    Nothing I've built has fallin down , yet , to my knowledge .  I've seen some stuff that is crap , I don't build it that way , I learn everyday from what I repaired by other each day   HTBH  ;)PEG  

[deercamp14x28]

Off to work so can't write much now, but...

This is in central Mississippi so no real worries about snow load...

[Jens]

Well,I think you will be fine.  A shed roof doesn't have nearly the weight of a gable roof, and with weight split between the ledger and the beam, no snow load, etc, you should be alright IMO.  In the future, keep in mind that if you have a main load bearing post, in the house or outside, you need to have solid transfer of weight all the way through to the foundation.  

[deercamp14x28]

For the record, the posts for the shed roof will probably be pulled back from the front of the deck about 6"-8", so they would actually be about 1' out from the beam location.  Maybe that would be enough to offset my concerns?

[Dan]

How about running the cedar tree-posts through the deck to new footers, and lay the decking around it so that it looks like the "trees" were there first.

[John Raabe]

Actually, looking at it, I think Deercamp will be fine using that deck for the roof load. He is not going to have a 100# snow load and has only a light metal roof.

If you look at the image:



Come up at a 45º angle off the support beam and up through the joist. Where it lands is where the joist STARTS acting as a cantilever. Now, consider that the decking and wall plate will move and spread the wall load over a larger area of the joists... Well, I just can't imagine he would be capable of getting enough load out there to do anything more than STIFFEN the floor joists.

However, I've not engineered this and I can't speak for your inspector.

[DavidLeBlanc]

Couldn't you put the roof pillers over the beam and cantilever the roof the same 18" as the deck? (maybe with angles from the edge of the roof back to the roof pillers?

[PEG688]

What I see in the pic is a 2x8 joist hung on a 2x12 rim with the rim higher than the joist I also see a odd step at the door as 2Xdecking will not make up the difference .   Always try to put the difference If there has to be one below so the decking  covers right up to the building, not a rim sticking up decking dieing into it  .  You all need to do full scale drawing in section so you can see how one thing effects the other  .   When I was in the cabinet shop I drew up details full scale  , if you all did that , spent time planning not in your mind but on cardboard that in it self would answer some if not all of your questions .  Believe me all builders if they want to get it right spend some  time drawing it up , if they tell you they don't they are fibbing ya or spend time changing it   With some sheet goods costing $100.00 plus  a sheet or more profit is in identfly the details and cutting once   HTBH  ;)PEG  

[glenn kangiser]

I dunno PEG- I do 'em in my head, cut 'em with a chainsaw then drive 'em in with a sledge hammer - but then again- I've never been accused of doing any fine carpentry either.

"I cut it three times and it's still too short." :-/

[PEG688]

Ah ya sure . If it don't go easy get a bigger hammer Jee it should fit    Tell me again "Why it's to short "    A little force is good    She'll be tight .    When will that replacement gluelam get here    Ah huh heard um all   Said even a few    No bodys perfect . HTBH  ;)PEG

[PEG688]

Could be I'm working from the specific back to the general , as aposed to the other .   One of my mentors would say "Do something, even if it's wrong , we can fix it tomorrow. "   There is a point of over figuring and the joy of building is lost .  FROZEN  can't cut , can't build , seen it in friends who have used my shop , me the mentor . I let them use it and me still , they could freeze up   Most just needed a nudge , one guy just quit    Other family issues came out in the end ...Theres a point of going where fools fear to tread,  and just doing poor work cuz you don't do the research.   Balance    Have a plan , do the research , ask when you don't know  "When in doubt , build it stout , with something you know about !"HTBH  ;)PEG  

[Bart_Cubbins]

I think PEG is right to draw attention to the ledger... it appears to be bolted to the house mostly through the top half while the joists hangers are attached to the bottom half. That can lead to failure of the ledger, as described in this story...

http://www.jlconline.com/cgi-bin/jlconline.storefront/42c6323a0017ac1927177f0000010572/UserTemplate/82?s=42c6323a0017ac1927177f0000010572&c=e78bf25430c0f61af5e3875903bd660d&p=1


"My conclusions were threefold," Bishop told JLC in a telephone interview. "The initial problem was that the ledger was attached directly to the siding with no weather protection. That allowed moisture to get between it and the building, and it began to rot. The second issue was that the lag screws were too few and far between, and they were driven through the ledger with a rotary hammer rather than through pre-drilled holes, which induced a splitting force. And then, all of the screws were in exactly the same plane, so that the splitting force was aligned along the entire 57 feet of ledger. The straw that broke the camel's back was that the builder used 2x8 joist hangers on a 2x12, so that all of the weight was distributed to that ledger below that plane of lag bolts."

Even though your deck is low to the ground, I think it'd be a real good idea to replace the hangers with top mount hangers and raise the joists to the top of the ledger.

Bart

[PEG688]

That always happens to the other guy  :-/  Doesn't it   HTBH  ;)PEG

[Jens]

Although I think that pretty much anyone on this forum wants to improve their skills (hey, some people might not), it is important to remember that there are people from all levels of skill here.  The reason I am writing this, is because some of the words seem beligerent to me, in a, "you don't know any better and don't seem to care, and that is why there is so much substandard housing everywhere".  I personally try to do everything to the best of my ability, and knowledge, and am pretty sure that everyone else here does too.  PEG...I get your sense of humor, but some people may not.  The bottom line to me, is that as long as it is not going to fall down it is better to build a house which is imperfect, but finished, than it is to build one which is perfect and unfinished.

Cheers

[PEG688]

Hobbiest    I really don't mean to send that out , I was Razzing Glenn some what .  So I'm I providing to much info ??    I would contend that some of the poorist built house are built by contractors , speedy , framing companys . Look at Homestead FL . Had the sheeting on the roof been nailed properly the blow off rate would have been lower.  The deck Bart showed was built by" PROS  " more than likely  it ""was on"" a condo .   I'm trying to provide my knowledge to those who ask , it's worth what your paying for it .   Could be my dry R.I . since of humor .   I could read into your message that "Hey butt out , these are my people !"  But with only 20 post your not over indulging .   Really just helping,, where I can,,, with what I know about .   HTBH  ;)PEG

[Jens]

Nope, no but out intended, I just know that my sometimes dry sense of humor does not always elicit understanding.  20 posts?  Yeah, well, I have been kind of doing a full on remodel of my house, 10-12hrs most days, 7 days a week most weeks, since February, as well as taking care of my 3 kids while my wife is at work, so hopefully you'll excuse my low numbers.  Post when necessary, leave most of the conversational posting to others with more computer time (usually).  almost done with the interior of the house though, and then finish what I couldn't on the exterior before the late winter hit, and sell it (thank God it will be over...for now).  I have been a framer, finisher, painter, none of them for too long, but have been building all manner of things since I can remember.  My family is the kind where, if you don't have the money, you build it.  Sometimes when you do have the money you build it anyway.  What is your background BTW?  You do seem knowledgable.  Please excuse the pre-emptive strike, but just want to make sure to see everyone included.  Exclusion is the worst form of punishment, because usually you haven't done anything to warrant it!  Oh, just found the site a few weeks ago too.  As I have said before, everyone here seems really kickass, and I enjoy seeing all the projects.

Cheers,
Jens

[PEG688]

Hobbiest  I'll try to be breif but complete.  Started as a the grunt at 15 , was leading framing crew at 19.   In R.I.   Did 4 years USN as a Aviation electrian .  This moved me to Washington state where I have lived since .  Went back into const. got a job with a millwork shop / G.Contractor . Learned to build cabs and case work for resedental and commericial projects , went back in the USN in 1986 got out again in 1990 . Back into const .   Worked for another cab shop / GC type company doing mid to high end custom work , lots of remo work . Not a lot of new construction some say 75 /80 % remo .  I've jacked up whole house shored up more .  Even in 1991 jacked up a boat house in a marinia . pulled a barged inside , jack it up cut the old floation free , slid new floats back in place , even had a under water P.Treated truss so the hull could pass over but the end of the boat house not get ripped apart by the wind again.  It was a grandfather deal if you moved the B/H out,, it was done , had to be done onsite if you will .  I've had my own company , but didn't like the  questions / Looks people would give me when I gave them  fair and honest bid .  I'm  a lead carpenter for a small 6 person company right now have been for 3 years . I'm 49 right now , so I've done a bit of building worked from detailed plans to no plan,, figure it out as you go,, sort of stuff.  I still dig holes pour concrete , talk to clients deal with every day issues .   Had a great talk with our Engineer just yesterday about a prow front place we are going to be building soon . Very good talk he listened,, I listened ,,and different ideas where looked at .   I could go on but this should give you a good idea of my back gound .  HTBH ;)PEG