Deck Questions (Off Topic)

[dthor68]

Garage Journal is the busiest forum I have ever been a part of, you can get answers quick here. So, please excuse me for asking this off topic question. But it is still a form of construction.

I am building a simple 12 x 12 deck. One side of the deck is going to be attached to house via ledger board. The other side of the deck is going to be held up with a drop beam attached to (3) 6 x 6 post. The "free plans" I have call for 2 x 10 joist and a double 2 x 10 drop beam. 2 x 10's are 9.5", that is a total of 19". I have 21 7/8" to work with. That puts the drop beam less than 3" off the ground.

Could I use a double 2 x 8 drop beam instead giving me 2 more inches of clearance from ground. Or, stick with the plans 2 x 10's? It will be painted so it should hold up to the elements well.

 

[ItsNemo]

Use pressure treated for the entire frame either way, paint won't do anything. If you're worried about height, could put 4 posts in to reduce span and move down to 2x8 and/or triple up the beams on the same spans, just have to find a span calculator. Could also do 2x8's for the joists if you put in a middle support beam (6 holes).

 

[850xpeps]

Ya agree with nemo. Pressure treated. No way I hell would I put painted lumber as a deck frame. Pwf if possible. I think you would be fine with 3 ply 2x8. But I don’t see an issue with the beam being 3” off the ground if the ground slopes from the house to let water drain away.

 

[Shiftless]

When you double those 2x10s you sandwich them together. I use Simpson 3 inch hex drive construction screws in a zig zag pattern to essentially form a 4x10 beam. NOT 19 inches!
Others are correct in recommending PT lumber. anything else will rot and fail with perhaps catastrophic results.
Also, the attachment of the ledger board to your house has specific requirements too. Don’t forget the joist hangers where your joists attach to the beams. Don’t just nail ‘em up!

 

[Bretny]

When you double those 2x10s you sandwich them together. I use Simpson 3 inch hex drive construction screws in a zig zag pattern to essentially form a 4x10 beam. NOT 19 inches!
Others are correct in recommending PT lumber. anything else will rot and fail with perhaps catastrophic results.
Also, the attachment of the ledger board to your house has specific requirements too. Don’t forget the joist hangers where your joists attach to the beams. Don’t just nail ‘em up!

I would hope that he didnt think a double 2x10 would be stacked verticaly. But if hes useing 2x10 floor joists and 2x10 beam and the deck needs to be 21/22 in off the ground then yes it would still be 2in off the ground.

 

[ard]

And don't forget to seal any cut ends in the PT lumber. I use a green copper based preservative. Pour some in a tub, stand the cut end into it for 10 minutes.

There are other tricks to build a water-shedding deck... Basically 'if water falls on top, how do I let it drain through and no great into my wood and framing. Google is a friend.

 

[dthor68]

Come on folks, it is a deck. Do I really need to say I am using PT lumber, that should go without saying. And you can paint PT lumber, it will last longer than any stain.

A 2 X 10 is actually 1-1/2" by 9-1/2". When you place a 2 X 10 joist on top of a 2 X 10 beam that comes out to 19" (top to bottom). That puts the 2 X 10 beam 2" off of the ground. And when I say beam/drop beam I am talking about a beam that is 2- 2 X 10's nailed together, making it a 4 X 10 (3" X 9-1/2"). The 3-6 X 6 post that hold the beam will do so notched out 3 X 9.5" so that the beam will rest in the notch. Thus the post will hold the beam, the beam will hold the joist and the joist will hold the decking.

My only question was could I use a (2x) 2 x 8 beam instead of a (2x) 2 x 10 beam giving me 2 more inches of ground clearance?

 

[Shiftless]

You can get the clearance you want by attaching your joists to the outer double 2x10 beam with joist hangers rather than putting the beam under the joists.
Here is a pic.

 

[Turbo]

You can get the clearance you want by attaching your joists to the outer double 2x10 beam with joist hangers rather than putting the beam under the joists.
Here is a pic.

Winner! Terry

 

[850xpeps]

Come on folks, it is a deck. Do I really need to say I am using PT lumber, that should go without saying. And you can paint PT lumber, it will last longer than any stain.

A 2 X 10 is actually 1-1/2" by 9-1/2". When you place a 2 X 10 joist on top of a 2 X 10 beam that comes out to 19" (top to bottom). That puts the 2 X 10 beam 2" off of the ground. And when I say beam/drop beam I am talking about a beam that is 2- 2 X 10's nailed together, making it a 4 X 10 (3" X 9-1/2"). The 3-6 X 6 post that hold the beam will do so notched out 3 X 9.5" so that the beam will rest in the notch. Thus the post will hold the beam, the beam will hold the joist and the joist will hold the decking.

My only question was could I use a (2x) 2 x 8 beam instead of a (2x) 2 x 10 beam giving me 2 more inches of ground clearance?

Don’t be lazy and find your own span table then. You didn’t say pressure treated so we’re idiots for not assuming? You said you were painting the wood. So what would we take from that?

And most 2x10 are actually 9.25” tall. Something that hasn’t dried out yet might be 9.5”.

It should go without saying it’s prob a good thing his paragraph or yours came after people’s help.

 

[dthor68]

You can get the clearance you want by attaching your joists to the outer double 2x10 beam with joist hangers rather than putting the beam under the joists.
Here is a pic.

In my case I could not. I have a septic tank that is in the way. I had to put my footings at 10' from my house. So a 12' deck needs a beam, 2' overhang. A 10' deck would have been much easier, but the queen wants a future pergola.

 

[Shiftless]

You’re building a deck over your septic tank?

 

[dthor68]

Don’t be lazy and find your own span table then. You didn’t say pressure treated so we’re idiots for not assuming? You said you were painting the wood. So what would we take from that?

And most 2x10 are actually 9.25” tall. Something that hasn’t dried out yet might be 9.5”.

It should go without saying it’s prob a good thing his paragraph or yours came after people’s help.

I have looked for a span table, no luck. I did manage to find a table on overhang (cantilever).

 

[850xpeps]

I have looked for a span table, no luck. I did manage to find a table on overhang (cantilever).

Couples words on google got it

 

[dthor68]

You’re building a deck over your septic tank?

Yes, about 16" corner opposite clean out.

 

[dthor68]

Couples words on google got it

Nothing there answering my questions.

 

[Shiftless]

Yes, about 16" corner opposite clean out.

Will your project be inspected? You might be limited with a 5 foot clearance requirement.
If it isn’t to local code (too close to septic tank or drain field) your future pergola won’t be legal either.

As long as you’re at it, if you’re pretty sure you’ll be building a pergola in the next few years, I would build the deck with that in mind and properly frame where the pergola support posts will go. The vertical loads on the posts should be properly supported and not just resting on some deck boards in between joists.

 

[dthor68]

Will your project be inspected? You might be limited with a 5 foot clearance requirement.
If it isn’t to local code (too close to septic tank or drain field) your future pergola won’t be legal either.

As long as you’re at it, if you’re pretty sure you’ll be building a pergola in the next few years, I would build the deck with that in mind and put footings where the pergola support posts will go. The vertical loads on the posts should be properly supported and not just resting on some deck boards in between joists.

No inspection. Actually the 10' deck that was built with the house was closer to the tank than the new. I moved the new 4' back. The old deck set on (3) 3" thick concrete blocks, no footings.

And I did find a table that states (2) 2 x 8's cover 5' 11" from post to post which is good.

Appreciate all of the help folks.

 

[AllThisStuff]

Does your city not need permits for decks?

 

[ItsNemo]

Does your city not need permits for decks?

A lot of places don't require permits if the deck isn't over a certain height (usually 2 feet) from the ground.

 

[73fxe]

I think that You better wait a year after You build the framing if You are planning on painting the framing. PT wood is real wet and paint won't last if the wood isn't dry.

 

[joey1320]

My building department doesn't need permits for a deck(and shed) under 10'x10'. That is unless it's attached to the house via a ledger board. If a ledger board is used, as opposed to a floating deck, inspections are needed for the whole process.

Check with your building department - if that's the thing you want to do.

 

[Matt Matt]

A lot of places don't require permits if the deck isn't over a certain height (usually 2 feet) from the ground.

Most permits are needed/required if it exceeds 24 inches in height at its highest point to ground, attached to any existing building and exceeds 100 ft.²

These three simple rules implement dozens of other rules.… Like proper fastening and fasteners, Heights of handrails, stringers, footing loads, cantilevers and lumber selection with adequate spans. Building codes should be always reference to especially when a roof or snow load might apply.