out door deck subframe spacing

[workinallthetime]

anyone have any specs on the subfloor spacing of a wooden out door deck? i plan on using 6x6 post along the outside for effect and 4x4 where you cant see them under the thing. i also plan on using 5/4 x 6 x 12 deck boards. the deck will be 12 x 43 and HAS to be off the gound about 24" in the highest part. what spacing should i use for the sub floor? would 16" centers work w/ 2x6 or should i do different?

 

[firefighter9208]

I always build a deck like I am building the subfloor in a house. I built a 16x40 deck on the back of our house and I used a 2x12 band with 2x10 floor joists on 16" centers. The deck is 4' off the ground. You'd be suprised how many people you can get on a deck that big and I don't think 2x6 floor joist would be big enough. JMHO

I built a 10x30 deck on my parents house and used a 2x10 band with 2x8 floor joists on 16" centers. The deck is 8' off the ground (above ground basement) and is solid as a rock. I bolted the band to the house with 3" x 3/8 galvenized lag bolts.


Chris

 

[EddieWalker]

16 inch centers would be the best, but allot of people build them on 24 inch centers to save a few bucks. I wont' go that far myself as the 5/4 decking will get bouncy over time and wear faster.

The same is true with using 2x6's for your joists. How far apart are your posts going to be? If more then four feet, I'd double up the 2x6's, or go up in size depending on your post spacings.

My last deck had 4x4 posts on 6 foot centers with 2x8's 12 feet long for joists. I like to overlap my joists to tie it all together. I also use screws and never nail a wood deck. The wood will shrink on you and the nails will work themselves loose over a short period of time. Two screws per joins on the decking. One will just cause the decking to curl.

Some people say to always lay the decking the the grain curled down, but each board will have it's own natrual cup to it. I always work with the board and take advantage of it's natural cup to shed water.

If you can, buy your material a month or two before you build. Preasrue treated wood will dry on you and shrink quite a bit. 5/4 inch decking is REALLY bad at shinking. If you can't wait for it to dry out, be sure to install it tight. Do not leave any spacing. It will shrink on you more then you want anyway.

Before you do anything, go to the magazine and book sections of Home Depot and Lowes. They both carries all sorts of information on deck building. Some of it is overkill, but if you follow the plans in those books, you won't go wrong. Mistakes happen when taking shortcuts and trying to save a buck with wider spacings and thinner lumber.

If you set your posts in concrete, be sure to build up the concrete above grade and slope it away from your posts. Posts always rot out at the level of the ground around them. If the cement comes above the ground and is sloped to shed water away from the posts, they will last much, much longer. Some instructions say to put a rock or something under the post to keep it off the bottom of the hole. I've removed my share of fence posts and have never seen the bottom of the posts rotted enough to make any difference. They will rot out at ground level decades before they will rot out from the bottom. I also wonder if the rock, or gravel at the bottom of a hole will actually hold water longer then just putting the post on the bottom of the hole and backfilling with dirt or concrete?? I never use gravel or a rock on the bottom of my posts.

One poster here suggested putting tar paper down on the top of the joist to shed water off of them. Then the decking goes on over the tar paper and the joists. You will never see the tar paper, but it will protect the tops of the joists from standing water. It sounds like a really good idea to me, and something I've started to do myself.

Eddie

 

[workinallthetime]

good ideas guys !!!
i like the tar paper and i like the 2 x 8 or double 2 x 6 ideas. this deck is in the very early stages of planning, the deck will serve as yet another seating place around the pool. i have not decided on post spacing yet only that i have to use 6x6 to match some existing work i did. the last deck i built was about 8 years ago and i ussed 2 x 8's for the decking. i pulled each board together with a clamp and a cleat before i screwed them down and ended up with about 1/16th to 1/8th gap over the years. i also have pulled lots of fence post and have yet to see one rotted at the bottom worse than the top. ever pulled a tie wall down and found the dead men ties to look brand new and the actual wall to be rotted away? i think the gound acts as some kind of insulator but who knows. agree on the dome top concrete also but using sonna tube is overkill for post only 2 feet in the ground. i dont like the method for setting post on top of blocks out of the ground, just looks wrong. next time im at the depot i will look at some books and post pics as the project gets under way.

 

[WayneB]

When we started our new porch at camp we went ahead and used 2x10 (16 on center). Support post were 6x6x16 and 6x6x12's a bear to handle. We sunk the 6x6 post 4 feet into the ground.

When we did the roof we selected 2x8x14 and the collar ties are 2x8x12, cut to fit! The location of the deck / porch faces north / northwest and we do get some pretty heavy winds and most of the storms come in from the northwest so we went a bit heavy on the structure.

We did the work this past fall right up into December and then it was just too cold and we were worried about the snow coming so we put the finish off until spring. Going up in two weeks to check thinks out and start working.

Prepare your BOM and do it with different lumber 2x8's and then with 2x10" so you can get a feel for what the over-all cost will be to increase the lumber size. The deck will be there a long time so it is worth putting in the extra lumber.

Just my thoughts

Wayne

 

[inveresk]

If you're going for permit, best check with your building inspector. Load/span tables might well be given in your local building code.

Otherwise, as a rough rule of thumb, you can work out joist size for a given span by halving the span and adding an inch. For example, a 14 foot span would work with 2 x 8" joists (14 divided by 2 plus 1). This assumes normal residential floor loading for live and dead loads and joists spacing of 16". If your joists are less deep you'll either get deflection or a good deal of bounce. If at times you're likely to load the deck over and above what could be considered normal, go up a joist size.

 

[Timber]

I am currently building a 16x52 deck with a pergola of the same size. I have built several Decks and I typically use 2x10 construction 16 in center for the deck and 24 on center for the pergola. I also prefer to set a deck on sauna tubes rather than planting the posts. You didn't mention it it is free standing or attached. Regardless you have to be sure the Rise and tread fall into code. That may determine the hight of your deck. How your deck is constructed is determined by your location,the style, weather it is free standing or attached with a ledger board to the sill plate or the foundation. You can cantilever 2 to 3 feet depending on you local codes. How you lay your decking will impact your framing as well. The first thing you do is draw it out to scale. I make blueprints my self but a scale drawing on graft paper is fine. If you buy your lumber ahead of time like Eddie suggested to dry be sure to stack it properly so it doesn't twist. I also suggest dimensions that eliminate waste. Lumber is sold buy the linear foot so if your cutting off 2 feet and tossing it away your wasting a lot of money. Proper planning is done in the drawing. 43 is a bad dimension keep to even numbers. If your set on 43 feet take the end decking boards and run the same direction as the stringers and you will take up that foot 6 inches on each end. How ever it will cost you 2 extra stringers. It will look nicer that way too just Miter the corners. At 24 inches off the ground that is 2 steps 3 rises to the deck at 8 inch rises standard code no Higher. That also gives you the option of no railings if you want to wrap the deck with steps. You also don't want to use all 12 foot planks, Use 12's, 10's, 16's, and 8's. You want to stager the joints. The rule is at least to rows before you repeat the pattern


This is a 24 inch deck I built that is a 10X12 landing that the steps to access the house and the main deck. The deck I am currently building is going to be of the same design

 

[RPK]

It is usually easiest to design a deck by starting with the deck boards. Exterior decks need to be designed to support a 40lb/sq.ft. load. When using 5/4 deck boards 16" on center joists are a must. Trex and most all of the types of high end decking need 12" on center joist spacing. 2x6 joists are only good for about 8 ft of clear span at 16" on center. 2x8's are good for 12 ft and 2x10's are good for 16 feet. Using that information and knowing the overall size of the deck you can determine how many carrying beams will be needed. The size of the carrying beam(s) are determined by the size and number of concrete piers. The more piers the smaller the carrying beams
RPK

 

[workinallthetime]

good points timber and all you guys.
i guess i should give you guys a little more detail about the site and my ideas
1st the site
the length is 43 aprox and the width is 12
12 foot width was determined for demensional lumber
the deck will sit slightly above an existing rock wall on the pool side and the back side will be tucked close to but not touching a hill that i will dry stack sandstone on before i start. under this deck water flows when we get alot of rain and the soil is pure clay and rocks. i dont get any kind of debris floating through this area just a little stream that is spread out.
the railing will be made of 4 x 8 sheets of lattice hung between 6x6 pt posts. ive had good luck with my design for that in the past. this deck will serve as a sun area and entertainment area for the pool and there will only be 2 places to step up to the deck which will probably be made from natural stone.

if it rains tomorrow i will not be able to do much so i can get some pics for you guys to see.

Yahoo! Photos - theglenlane_barn@sbcglobal.net's Photos - house work

here are some pics of before and after work and some unfinished work ive done around the place in the past couple years.

 

[EddieWalker]

Two things realy cought my attention.

First, the water flowing under the deck. I know it probably not feasable to change this, so it's very important that you ditch the ground to keep the water away from your posts. Also be sure to grade the slope to keep the water moving. Standing water will lead to mold and bugs. Is there anyway to catch the water before it gets to the deck and channel it through some sort of pipeing?

Second is the lattice. I understand it's fairly quick and easy to work with, but I've never seen it last more then a few years before starting to break. I've used it myself, and probably will again if a client insists, but I'd really try to find another material. Those books at Home Depot and Lowes will have all sorts of alternatives. One Idea I've been kicking around for an outdoor railing is rebar. I want to leave them unfinished and let them rust. I've seen copper pipe that had an amazing patina that was really nice that I'd love to try sometime.

Eddie

 

[workinallthetime]

ive toyed with the idea of making a wrought iron hand rail all the around the thing,
i will compensate for the water when i build by elevating the concrete above grade and possibly using some sort of metal pipe post with welded brackets to support the subfloor

as for diverting the water, out of the question w/o major time and expense.

 

[Timber]

I thought I would post these hear as I am building this deck with the same rise as yours



This deck is going to be 16X52 feet. The rise off the pool deck is 24 inches. That is the hight of the foundation at the bulkhead. The decking will cover the foundation so the bulkhead appears to be sitting on the deck. From the deck it is 24 inches to the slider's. There will be a 3X6 foot landing in front of both sliders and the steps will wrap 3 sides as will the entire deck. So if your following me hear the deck comes off the house 16 feet & the steps have an 8 inch rise & a 10 inch tread. The bottom step will cover 6 inches of the patio around the pool for the entire length of the deck.



I dug my holes for my sauna-tubes at about 40 + inches. I use all 2x10 construction and I have a 24 inch rise so I need space for 20 inches of lumber and I want my tubes above the ground. I set a line level to give me 22 inches to play with. I cut my sauna-tubes and poor cement and screed it off at the top of the tubes and set my J bolts. The other thing is I am going to cantilever the deck 2 feet over the tubes on the length and width. I will bolt a 6x6 plate to the sauna-tube and then a 12 inch 6x6 to the plate. My carrying beam will be two 2x10s Bolted to each side of the 6x6 upright,Then my 2x10 stringers will then sit on top and overhang 2 feet minus the end cap. The other end at the house I will drill and anchor the sill plate to the foundation with wedjit bolts. and then collar tie in my stringers. I will do the same on the front side of the bulkhead

I hope you could follow me, It might give you some ideas. feel free to ask anything.

 

[workinallthetime]

I thought I would post these hear as I am building this deck with the same rise as yours



This deck is going to be 16X52 feet. The rise off the pool deck is 24 inches. That is the hight of the foundation at the bulkhead. The decking will cover the foundation so the bulkhead appears to be sitting on the deck. From the deck it is 24 inches to the slider's. There will be a 3X6 foot landing in front of both sliders and the steps will wrap 3 sides as will the entire deck. So if your following me hear the deck comes off the house 16 feet & the steps have an 8 inch rise & a 10 inch tread. The bottom step will cover 6 inches of the patio around the pool for the entire length of the deck.



Now I dug my holes for my sauna-tubes at about 40 + inches. Now I use all 2x10 construction and I have a 24 inch rise so I need space for 20 inches of lumber and I want my tubes above the ground. I set a line level to give me 22 inches to play with. I ct my sauna-tubes and poor cement and screed it off at the top of the tubes and set my J bolts. The other thing it I am going to cantilever deck 2 feet over the tubes on the length and width. I will bolt a 6x6 plate to the sauna-tube and then a 12 inch 6x6 to the plate. M carrying beam will be 2 2x10s Bolted to each side of the 6x6 upright. My 2x10 stringers will then sit on top and overhang 2 feet minus the end cap.

I hope you could follow me might give you some ideas. feel free to ask anything.

first question is
how the heck did you post pics straight into the thread? i always want to do that.
i ragged on sonna tubes before but now im eating my words because i think due to the moisture condition where i am putting mine i may need to go that route.

whats the spacing on your tubes?>

 

[Timber]

LOL I Learned that from Rob (3rrl) I use Photobucket. Its a free image hosting account. I load my pics there and then I select an image and scroll to the bottom and click on generate HTML image. It then gives you several choices. I just copy and paste it into my post were I want it. I thing many members use this procedure. I use the click-able thumbs but there are other options
Image hosting, free photo sharing & video sharing at Photobucket

 

[workinallthetime]

ok guys here is the spot
the fence and the deck thats there i did not build!!!!!!o!
the deck will look like it is setting on top of the unsightly wall and the fence will be gone
as you can see from the pics the spot is kind of awkward, there is exactly 12 feet from the front of the wall to the hill
i could actually set my post where they would hardly ever be in the water by moving them out twords the ends. if i can canterleaver 2 feet then that leaves the largest span between post at 8 feet, that seems like a big span to me.
did i also mention the wall has a curve to it and so does the hill, thats why i was going to run the decking the 12' way instead of the 43 foot way plus the far end is longer than 12' due to the wall turns in alot

 

[EddieWalker]

Thanks for the pictures, they help allot. I'm still a little confused on what you're goal is. Is this deck for entertaining around the pool? Sort of a nice place to set up tables, and relax?

When I looked at your pictures, I imediatly saw a perfect location for concrete patio pavers. The wood deck sort of seemed forced and out of place to me, but pavers really jumped out at me. I saw them coming off of the edge of the concrete around the pool, through the existing wood deck and out past the trees/shrub that you have there now. I'd either remove them, or take one out and build around the other.

Pavers are very simple to install and when you are done, they will be there forever. They cut real easy with a masonary bit in any power saw and you can do as little or as much as you want. Nothing wrong with doing a small area this year, then adding to it next year.

Anyway, that's just an idea that hit me.

With your drainage and water issues, the sono tubes should be mandatory. I wouldn't even mess with wood posts with as short a rise as you have, just pour the concrete up to the point your joists need to be and attach them directly to the concrete. You can also drill your holes in the ground and put rebar in them so it extends up past the hole to just below the height you need them to be. Then slide cinder blocks over the rebar and fill the cavities with concrete. You will have permeanent posts that will never rot and be imune to the water. Just be sure you measure your height first so the cinder blocks line up at the right point. There is no need to morter the blocks when you fill them with concrete for this.

Eddie

 

[workinallthetime]

the deck that is there will be gone along with the fence and crepe myrtle things. i hate all 3 !!! the old man that lived here built the deck using nails, so you can imagine im out there every 2 weeks knocking them back in so someones toe does get ripped open.
as for the concrete pavers good idea but no, i have used natural stone everywhere i can around here, i have a friend who owns several rock quarries and where i can get smooth stone for walks. my yard is full of sandstone that work great for building walls.
sonna tube yup think im going that route or something close to it.

 

[ktm250rider]

Precast piers could also be used. They may cost a little more than the sono tube and cement components. However, once the hole is dug, just drop'em in and back fill.
If you want to run your deck boards in the 12' direction, then your framing would have to be done in the 43' direction. If Im thinking of this correctly, its gonna be hard to frame anything if your framing is running parallel to the hill.
To accomodate the curve, I would run your 2x10 framing perpendicular to the hill set on a 2x12 3 ply beam. You should be able to get your 2' cantilever with this. Cut the floor joists to match the curve you want. I would put in blocking at the minimum joist length over the entire width (43') of the deck. With the curved floor joist, use 1x boards to form to the curve. Use two of them with the outer one larger than the inner one and raise the outer one to be level with the finished decking. Run the decking at a 45 to the framing. Then you can cut the decking to match the curve. THe second trim board on the front will cover the cut ends of the decking.
2x12 3 ply beam, 8ft span should be ok. Check with building inspector to get local codes to be sure.

 

[mikim]

concrete piers fer sure ....when laying the deck boards ... I always like to run mine at 45 deg ... allows 3 screws at each joist and adds interest. There are new (to me) fasteners out there now too that you fasten the deck boards from underneath - or the side - so there are no screws showing at all. Are you going to hide the wall under the deck? if so - any chance it can be used for some support? .......... With the pool, the hill, and the wall, you have a chance here to build something with a lot of interest. I wouldn't hurry into it.... and wouldn't hurry the build either. Take some time and do it right the first time. Takes longer to do it over.

 

[workinallthetime]

concrete piers fer sure ....when laying the deck boards ... I always like to run mine at 45 deg ... allows 3 screws at each joist and adds interest. There are new (to me) fasteners out there now too that you fasten the deck boards from underneath - or the side - so there are no screws showing at all. Are you going to hide the wall under the deck? if so - any chance it can be used for some support? .......... With the pool, the hill, and the wall, you have a chance here to build something with a lot of interest. I wouldn't hurry into it.... and wouldn't hurry the build either. Take some time and do it right the first time. Takes longer to do it over.

when we bought this place our realtor was shocked that we even wanted to look at it. the house had 2 old people living in it and it was 3500 sq feet of nick nacks and 1979. we saw the potential with the land, the house, the pool, the rv pad and the woods. We take one room at a time and do a total make over on it, we tear it down to the concrete slab and bare walls and change everything. the outside is pefect for the guy who wants to display his tallents and ideas. we were here for a year before the septic went pop side up in the yard and after months of digging with a shovel and post hole diggers i said " baby buy me a tractor or im paying someone to do this" got the tractor when she foundout we could be looking at anywhere from 1500 to 15000 for septic repair. fixed the septic with 500 feet of new line and a 15000 bx23,lol. the tractor lead to more projects since i was unstopable now and now the tractor has led to full time tractor/lawn/landscape work. its amazing how one decision can take you so far. i burried the kids trampoline so its level with the ground, thats cool all the kids love it, ive built so many dry stack sandstone walls im getting tired of it,lol.
as for the deck this place has been such a good information sorce i thought i would put up a post and see what real people do and think. i can google with the best of them but thats not real people who do the job.

it would be great if i could use the wall, im just afraid it is to uneven and would be a possible moisture problem but maybe not. once i get a room reshot w/ texture and paint the hall ill start tearing up stuff to see what im dealing with out there. i got the "lets do it" from the wife so its just a matter of time and priorities until i get there.

thanks guys