# ledger not for decks



## Rick18071 (Aug 2, 2013)

I could use some help in finding somewhere in the 2009 IRC for ledger connections for a sunroom/addition floor. Lot's of things about deck ledgers for decks in the IRC but I can't find where ledgers are even allowed for anything else.


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## rogerpa (Aug 2, 2013)

*R502.6.2 Joist framing.* Joists framing into the side of a wood girder shall be supported by _approved_ framing anchors or on ledger strips not less than nominal 2 inches by 2 inches (51 mm by 51 mm).

*R502.10 Framing of openings.*  Openings in floor framing shall be framed with a header and trimmer  joists. When the header joist span does not exceed 4 feet (1219 mm), the  header joist may be a single member the same size as the floor joist.  Single trimmer joists may be used to carry a single header joist that is  located within 3 feet (914 mm) of the trimmer joist bearing. When the  header joist span exceeds 4 feet (1219 mm), the trimmer joists and the  header joist shall be doubled and of sufficient cross section to support  the floor joists framing into the header. _Approved_ hangers shall  be used for the header joist to trimmer joist connections when the  header joist span exceeds 6 feet (1829 mm). *Tail joists over 12 feet  (3658 mm) long shall be supported at the header by framing anchors or on  ledger strips not less than 2 inches by 2 inches (51 mm by 51 mm).  *

*TABLE R602.3(1)* *FASTENER SCHEDULE FOR STRUCTURAL MEMBERS*


*ITEM**DESCRIPTION OF BUILDING ELEMENTS**NUMBER AND TYPE OF* *FASTENER**a, b, c**SPACING OF FASTENERS**Roof*1Blocking between joists or rafters to top plate, toe nail3-8d (21/2" × 0.113")—2Ceiling joists to plate, toe nail3-8d (21/2"× 0.113")—3Ceiling joists not attached to parallel rafter, laps over partitions, face nail3-10d—4Collar tie rafter, face nail or 11/4" × 20 gage ridge strap3-10d (3" × 0.128")—5Rafter to plate, toe nail2-16d (31/2" × 0.135")—6Roof rafters to ridge, valley or hip rafters:

    toe nail

    face nail4-16d (31/2" × 0.135")

3-16d (31/2" × 0.135")—

—*Wall*7Built-up corner studs10d (3" × 0.128")24" o.c.8Built-up header, two pieces with 1/2" spacer16d (31/2" × 0.135")16" o.c. along each edge9Continued header, two pieces16d (31/2" × 0.135")16" o.c. along each edge10Continuous header to stud, toe nail4-8d (21/2" × 0.113")—11Double studs, face nail10d (3" × 0.128")24" o.c.12Double top plates, face nail10d (3" × 0.128")24" o.c.13Double top plates, minimum 24-inch offset of end joints,

    face nail in lapped area8-16d (31/2"× 0.135")—14Sole plate to joist or blocking, face nail16d (31/2" × 0.135")16" o.c.15Sole plate to joist or blocking at braced wall panels3-16d (31/2" × 0.135")16" o.c.16Stud to sole plate, toe nail3-8d (21/2" × 0.113")

or

2-16d 31/2" × 0.135")—

—17Top or sole plate to stud, end nail2-16d (31/2" × 0.135")—18Top plates, laps at corners and intersections, face nail2-10d (3" × 0.128")—191" brace to each stud and plate, face nail2-8d (21/2" × 0.113")

2 staples 13/4"—

—201" × 6" sheathing to each bearing, face nail2-8d (21/2" × 0.113")

2 staples 13/4"—

—211" × 8" sheathing to each bearing, face nail2-8d (21/2" × 0.113")

3 staples 13/4"—

—22Wider than 1" × 8" sheathing to each bearing, face nail3-8d (21/2" × 0.113")

4 staples 13/4"—

—*Floor*23Joist to sill or girder, toe nail3-8d (21/2" × 0.113")—241" × 6" subfloor or less to each joist, face nail2-8d (21/2" × 0.113")

2 staples 13/4"—

—252" subfloor to joist or girder, blind and face nail2-16d (31/2" × 0.135")—26Rim joist to top plate, toe nail (roof applications also)8d (21/2" × 0.113")6" o.c.272" planks (plank & beam - floor & roof)2-16d (31/2" × 0.135")at each bearing28Built-up girders and beams, 2-inch lumber layers10d (3" × 0.128")Nail each layer as follows:

32" o.c. at top and bottom and  staggered. Two nails at ends

and at each splice.*29**Ledger strip supporting joists or rafters**3-16d (3**1**/**2**" × 0.135")**At each joist or rafter*


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## Rick18071 (Aug 2, 2013)

So for a sunroom/ addition they cannot use a ledger. they would have to use joist hangers or a ledger strip right on the rim board. They can't build the sunroom/addition on a deck that is suported by a ledger that is to code for a deck, they would have to rebuild the deck without the ledger board and attach the joists direcly to the rimboard?


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## Francis Vineyard (Aug 2, 2013)

I can't find where the code prohibits enclosing decks.

Francis


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## cboboggs (Aug 2, 2013)

I don't think you would have to rebuild anything, you would just have to make sure the existing construction could support the increased loads.


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## Sifu (Aug 2, 2013)

Would there necessarily be increased loads?  Would the condition be potentially better since presumably the existing floor will not be subject to wet conditions any more?  Aren't the uniform loads for a deck the same as would be for a sunroom?  (40/10)


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## rogerpa (Aug 2, 2013)

You said; "not for decks". Now you have a deck???



> for ledger connections for a sunroom/addition floor


How is the existing deck supported at the house? Toe-nailed?  Is it code compliant now? Lateral load connection?

*R502.2.2.1 Deck ledger connection to band joist.*  For decks* supporting a total design load of 50 pounds per square foot  *(2394 Pa) [40 pounds per square foot (1915 Pa) live load plus 10 pounds  per square foot (479 Pa) dead load], the connection between a deck  ledger of pressure-preservative-treated Southern Pine, incised  pressure-preservative-treated Hem-Fir or _approved_ decay-resistant  species, and a 2-inch (51 mm) nominal lumber band joist bearing on a  sill plate or wall plate shall be constructed with 1/2-inch  (12.7 m) lag screws or bolts with washers in accordance with Table  R502.2.2.1. Lag screws, bolts and washers shall be hot-dipped galvanized  or stainless steel.

I doubt the sunroom would exceed 50 pounds per square foot design load.


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## Rick18071 (Aug 3, 2013)

ledger not for decks

We have a 40psf ground snow load plus the  dead load for the peaked roof plus the weight of the walls and windows coming down on the 2 sides of the deck. The end deck joists that are supported by the ledger would have to be beefed up to support the walls. Wouldn't this increase the load on the ledger?


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## Rick18071 (Aug 3, 2013)

Yes the ledger is done by code for a deck.



			
				Francis Vineyard said:
			
		

> I can't find where the code prohibits enclosing decks.Where does the code prohibit a car on a deck?
> 
> It's not a deck anymore. It's a floor.  Would you let them support an interior floor with a ledger?
> 
> ...


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## Yankee (Aug 3, 2013)

Rick18071 said:
			
		

> Yes the ledger is done by code for a deck.
> 
> 
> 
> ...


Framing can ether bear a min of 1.5" on something or it can be hung with hangers. Figure out what the loads will be and the service conditions and go from there. Don't let the code sections intermingle and confuse you.


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## Rick18071 (Aug 3, 2013)

But ledgers don't bear on anything or hung with hangers.


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## Yankee (Aug 3, 2013)

Rick18071 said:
			
		

> So for a sunroom/ addition they cannot use a ledger. they would have to use joist hangers or a ledger strip right on the rim board. They can't build the sunroom/addition on a deck that is suported by a ledger that is to code for a deck, they would have to rebuild without the ledger board and attach the joists direcly to the rimboard?


I don't see where is disallowed to hang the joists from a ledger board, or bear the joist on a ledger board.


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## Yankee (Aug 3, 2013)

Sifu said:
			
		

> Would there necessarily be increased loads?  Would the condition be potentially better since presumably the existing floor will not be subject to wet conditions any more?  Aren't the uniform loads for a deck the same as would be for a sunroom?  (40/10)


The supporting system needs to accommodate the roof and its loads in addition to the floor loads. So if it is an existing deck, the girder/posts ma be inadequate.


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## Francis Vineyard (Aug 3, 2013)

Rick there are many terms that are not defined in the code such as ledger board and others that have the dual duty as beams and headers.  What we may do is analyze or pull from other applications for guidance; for example floor attached to masonry walls in R606.

In effect what happens is the band board will work as a girder and with the ledger board as a built-up beam.  Could attach the ledger strip or hangers directly to the band board but would be more work to achieve the same result as adding a ledger board.

Deck is defined as a floor system and doesn't necessary have to be open to the exterior.

The new AWC DCA can be used as a reference where it prescribes attachments of beams but not girders to the ledger.  Similarly where "ledgers" are nailed to wall studs to support stair landing the method is not specifically in the code and yet inspectors will require joist hangers for joist attached to this board!

FWIW we have residential garages with wood decks or floors constructed in accordance with the live load table.

Yankee was able to post twice by the time I could edit with my slow internet connection so there's some redundancy.

Francis


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## Rick18071 (Aug 4, 2013)

Don't have my IRC with me but I know it says deck girders cannot be supported by a ledger. With this sunroom/addition they will have a girder with walls on it attached to the ledger. It seems to me that if you can't have a girder for a deck supported by a ledger you shouldn't have a girder that is supporting a floor, walls, and a roof to be supported by a ledger.


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## Francis Vineyard (Aug 4, 2013)

Correct; ledgers cannot prescriptively support girders, however most likely existing deck rimjoist that will support the wall/ceiling/roof becomes a beam not a girder.

http://www.thebuildingcodeforum.com/forum/residential-building-codes/10812-irc-beam-girder.html?highlight=beam+girder

Francis


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## Yankee (Aug 5, 2013)

Francis Vineyard said:
			
		

> Correct; ledgers cannot prescriptively support girders, however most likely existing deck rimjoist that will support the wall/ceiling/roof becomes a beam not a girder.http://www.thebuildingcodeforum.com/forum/residential-building-codes/10812-irc-beam-girder.html?highlight=beam+girder
> 
> Francis


 I would agree


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## Rick18071 (Aug 5, 2013)

Ok, so where is the table for beam spans if is not a girder?


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## DRP (Aug 5, 2013)

The girder and header table is a table of uniformly loaded beam spans.

But, the ledger attachment specs are for a uniformly loaded ledger. I agree with you that it would be inappropriate to attach a beam, girder, header... a concentrated point load, somewhere along the length of a ledger that was designed for distributed loads. The connection of the ledger to the supporting structure in that immediate area may, or may not, be up to the task. IMO the beam supporting the wall and roof needs to have its' loads quantified and the connection of the beam to the supporting structure would then be designed according to the referenced AF&PA's NDS. I've been wondering id the bams supporting the wall could not be inserted through the rim to rest on the mudsill. The remaining ledger would then carry the joists, if perpendicular to the house, as the intended uniformly distributed load. WCDD also has uniformly loaded beam safe load tables but I think the first hill to climb is the one you were first focusing on, connection.


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## Francis Vineyard (Aug 5, 2013)

Assuming a gable roof extending from the structure the beam supports the dead load of the wall (20 psf); the roof/ceiling load is split between the posts and wall of the structure. Another design to address is wind bracing with approved brackets or connectors in accordance with R602.10.9 (2009 IRC).

Shed roofs are similar.

Francis


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## Rick18071 (Aug 5, 2013)

Thanks. it is a gable roof but even if it wasn't it still would be supporting part of the roof. I am going to tell them it must be attached to the rimboard with a hanger or dig in a pier against the foundation.

By the way can't find the word beam anywhere in the IRC. And the only place I can find "ledger" is for decks, so I can't see using ledgers for anything else.


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## Francis Vineyard (Aug 5, 2013)

Does it matter?  See Definition: Height, Story; ceiling height in basement; Drilling and Notching; floor framing fastening; floor sheathing table; etc..

Francis


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## steveray (Aug 6, 2013)

The problem with 1/2" lags is they need to be embedded 4x the diameter...1-1/2" rim doesn't cut it.....or at least that is what the NDS or WFCM used to say



			
				rogerpa said:
			
		

> You said; "not for decks". Now you have a deck???How is the existing deck supported at the house? Toe-nailed?  Is it code compliant now? Lateral load connection?
> 
> *R502.2.2.1 Deck ledger connection to band joist.*  For decks* supporting a total design load of 50 pounds per square foot  *(2394 Pa) [40 pounds per square foot (1915 Pa) live load plus 10 pounds  per square foot (479 Pa) dead load], the connection between a deck  ledger of pressure-preservative-treated Southern Pine, incised  pressure-preservative-treated Hem-Fir or _approved_ decay-resistant  species, and a 2-inch (51 mm) nominal lumber band joist bearing on a  sill plate or wall plate shall be constructed with 1/2-inch  (12.7 m) lag screws or bolts with washers in accordance with Table  R502.2.2.1. Lag screws, bolts and washers shall be hot-dipped galvanized  or stainless steel.
> 
> I doubt the sunroom would exceed 50 pounds per square foot design load.


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## peach (Aug 7, 2013)

Rick18071 said:
			
		

> We have a 40psf ground snow load plus the dead load for the peaked roof plus the weight of the walls and windows coming down on the 2 sides of the deck. The end deck joists that are supported by the ledger would have to be beefed up to support the walls. Wouldn't this increase the load on the ledger?


unless it's a flat roof, the roof snow load will be less than the ground snow load.


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## DRP (Aug 7, 2013)

As I see it, the deck rim joists from house ledger to outer deck rim beam were uniformly loaded, they now support a wall and part of the roof, a healthy increase and point load on the ledger from the new rim beam that supports the bearing wall. This load needs to be quantified and the new beam connected to the house adequately.

Although the word beam may not appear, a joist, a rafter, a girder and a header are all types of beams. A ledger may or may not be able to resist the quantified load, quantify load and resistance to see. Simpson may ok the use of a hanger through the ledger into the rim, worth a call.

There has been some rewording on the lag penetration specs for deck ledgers, can't recall the specifics they're here somewhere, I switched to bolting.


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## Francis Vineyard (Aug 7, 2013)

Presumably the OP questions how the code address decks to be enclosed and it seems we are not on the same page as to how this is done without plan to look at.

Where is the load including snow on the deck when it's covered?





The addition of walls comes into play, now the question is can we make the rim joist a beam? It's never been a problem in the past without hangers but now the code says "Girder supporting deck joists shall not be supported on deck ledgers or band joists." I think this was a mistake and instead should be something similar to what the manufacturer instructions for the hangers in the DCA6-09 has for framing around chimneys or bay windows "when an engineer design is submitted in accordance with section R301.1.3 of the IRC." Question is this engineering provided in the DCA6-09 commentary for trimmer joist using the NDS? Some will require a seal for this but not required in all states.

Could you use this information in the DCA6-09 for framing around chimneys or bay windows for beams for example on wrap around decks at the corner where the orientation of joist remains perpendicular the the exterior walls or where a deck is frame into an inside corner? And what about where stairs are added to the rim joist do you require a header (beam) design with additional post underneath?

Some pictures that where apporved by an engineer had strapping added to the roof diaphram and walls to help carry the load! Yes that's brick veneer.









A picture just for the fun of it . . .





Francis


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## Rick18071 (Aug 7, 2013)

They are not building a sunroom on a deck, there was no deck there. It's realy an addition. The code only sepcifys ledgers used for decks.

When I get a plan for a wrap around deck connected to a corner of a house I mark the plans to install a pier at the corner against the house foudation to suport the deck girder.


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## GBrackins (Aug 7, 2013)

what if they run the "girder" back into the wall and it bears upon the sill plates?


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## Rick18071 (Aug 7, 2013)

That would be ok with me.


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## GBrackins (Aug 7, 2013)

floor joists hung from a ledger board in between the two exterior "girders". The sufloor would be attached to the top of the ledger (code attached ledger to resist lateral, uplift & shear) and all perimeter beams & joists to prevent any lateral movement for the joist hangers.


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