Rafter Connection to Top Plates

[Mule]

It's funny how you stumble across something every now and then! I was looking for the nailing schedule for joist to top plate connection and found....TABLE R802.5.1(9)RAFTER/CEILING JOIST HEEL JOINT CONNECTIONS a, b, c, d, e, f, gC states:c. Heel joint connections are not required when the ridge is supported by a load-bearing wall, header or ridge beam. Is this saying what I think it is saying?? Surely not!!!The reason I started researching was because of an installation of some ceiling joists and I could not see any nails connecting the joist to the top plate. I couldn't remember if it was 2 on one side and one on the other or?????? When I didn't see any nails I had one of those hmmmmmmmm thoughts! The framer said they were between the rafter and joist. I'm still not buying it so I had him add straps. Here's a picture.Click on image to enlarge,View attachment 253

View attachment 1355

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[globe trekker]

.

Mule,

Wouldn't Table R602.3(1) - FASTENER SCHEDULE FOR STRUCTURAL MEMBERS be the ' more restrictive '

application, thus requiring actual fastening of those heel connections to the top plates? Just asking...

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

DESCRIPTION OF BUILDING ELEMENTS

NUMBER AND TYPE OF FASTENERa,b,c

SPACING OF FASTENERS

Joist to sill or girder, toe nail

3-8d (2-½" × 0.113")

—

1" × 6" subfloor or less to each joist, face nail

2-8d (2½" × 0.113")

2 staples, 1¾"

—

—

2" subfloor to joist or girder, blind and face nail

2-16d (3½" × 0.135")

—

Sole plate to joist or blocking, face nail

16d (3½" × 0.135")

16" o.c.

Top or sole plate to stud, end nail

2-16d (3½" × 0.135")

—

Stud to sole plate, toe nail

3-8d (2½" × 0.113") or 2-16d (3½" × 0.135")

—

Double studs, face nail

10d (3" × 0.128")

24" o.c.

Double top plates, face nail

10d (3" × 0.128")

24" o.c.

Sole plate to joist or blocking at braced wall panels

3-16d (3½" × 0.135")

16" o.c.

Double top plates, minimum 24-inch offset of end joints, face nail in lapped area

8-16d (3½"² × 0.135")

—

Blocking between joists or rafters to top plate, toe nail

3-8d (2½" × 0.113")

—

Rim joist to top plate, toe nail

8d (2½" × 0.113")

6" o.c.

Top plates, laps at corners and intersections, face nail

2-10d (3" × 0.128")

—

Built-up header, two pieces with ½" spacer

16d (3½" × 0.135")

16" o.c. along each edge

Continued header, two pieces

16d (3½" × 0.135")

16" o.c. along each edge

Ceiling joists to plate, toe nail

3-8d (2½" × 0.113")

—

Continuous header to stud, toe nail

4-8d (2½" × 0.113")

—

Ceiling joist, laps over partitions, face nail

3-10d (3" × 0.128")

—

Ceiling joist to parallel rafters, face nail

3-10d (3" × 0.128")

—

- - > Rafter to plate, toe nail

2-16d (3½" × 0.135")< - -

—

1" brace to each stud and plate, face nail

2-8d (2½" × 0.113")

2 staples, 1¾"

—

—

1" × 6" sheathing to each bearing, face nail

2-8d (2½" × 0.113")

2 staples, 1¾"

—

—

1" × 8" sheathing to each bearing, face nail

2-8d (2½" × 0.113")

3 staples, 1¾"

—

—

Wider than 1" × 8" sheathing to each bearing, face nail

3-8d (2½" × 0.113")

4 staples, 1¾"

—

—

Built-up corner studs

10d (3" × 0.128")

24"o.c.

Built-up girders and beams, 2-inch lumber layers

10d (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.

2" planks

2-16d (3½" × 0.135")

At each bearing

Roof rafters to ridge, valley or hip rafters:

toe nail

face nail

4-16d (3½" × 0.135")

3-16d (3½" × 0.135")

—

—

Rafter ties to rafters, face nail

3-8d (2½" × 0.113")

—

Collar tie to rafter, face nail, or 1¼" × 20 gage ridge strap

3-10d (3" × 0.128")

—

(continued)

DESCRIPTION OF BUILDING MATERIALS

DESCRIPTION OF FASTENERb, c, e

SPACING OF FASTENERS

Edges (inches)i

Intermediate supportsc,e (inches)

Wood structural panels, subfloor, roof and wall sheathing to framing, and particleboard wall sheathing to framing

5/16²-½"

6d common (2" × 0.113") nail (subfloor, wall)

8d common (2½" × 0.131") nail (roof)f

6

12g

19/32² -1"

8d common nail (2½" × 0.131")

6

12g

11/8²-1¼"

10d common (3" × 0.148") nail or

8d (2½" × 0.131") deformed nail

6

12

Other wall sheathingh

½" structural cellulosic fiberboard sheathing

1½" galvanized roofing nail 8d common

(2½" × 0.131") nail; staple 16 ga., 1½" long

3

6

25/32² structural cellulosic fiberboard sheathing

1¾" galvanized roofing nail 8d common

(2½" × 0.131") nail; staple 16 ga., 1¾" long

3

6

½" gypsum sheathingd

1½" galvanized roofing nail;

6d common (2" x 0.131") nail; staple galvanized

1½" long; 1¼" screws, Type W or S

4

8

5/8² gypsum sheathingd

1¾" galvanized roofing nail;

8d common (2½" × 0.131") nail; staple galvanized

15/8² long; 15/8² screws, Type W or S

4

8

Wood structural panels, combination subfloor underlayment to framing

¾" and less

6d deformed (2" × 0.120") nail or

8d common (2½" × 0.131") nail

6

12

7/8²-1"

8d common (2½" × 0.131") nail or

8d deformed (2½" × 0.120") nail

6

12

11/8²-1¼"

10d common (3" × 0.148") nail or

8d deformed (2½" × 0.120") nail

6

12

Also, Section 802.3.1 [ in the 2006 IRC ], " ...and the rafter shall be nailed to the top plate wall in

accordance with Table R602.3(1)".

.

 

[Mule]

I agree but i just found it rather odd that the code would even state such a thing! And actually I forgot the connection of rafters was in the wall section....another screwy thing!

 

[globe trekker]

.

Mule,

You already know that there are a lot of odd / irrational / non-common sense sections

littered throughout all of the code books.

Always glad to help you, and everyone else! Plus, I need all the help I can get, ...every

day! Trying to remember all of these codes and sections and applications and updates

and new products & materials, ...well, it just gets to be overwhelming.

.

 

[georgia plans exam]

FWIW the commentary states that the fastener table for this situation uses Table R603.3(1) only if the roof live load is 20 lbs per sq. ft. or less. If over, the connection must be in accordance with Table R802.5.1(9).

GPES

 

[globe trekker]

.

GPES,

For those of us without the Commentary, how would the average inspector / plans examiner / BO

determine which section to use?

.

 

[georgia plans exam]

Globe,

Good question. I am trying to find a code justification for the commentary statement but, have not so far. That what the FWIW is about. I do mostly commercial projects. Anyone out there have an idea?

GPES

 

[peach]

I think you'll find 20 psf is the minimum attached to the minimum 90 mph wind speed. Look at Table R301.2(2).

A very gray area.. but it's up to the plan reviewer to determine.. don't dump it on the inspector.

 

[Yankee]

Well, I've used that section and made the assumption that the connection between the rafters and the ceiling joists need not be made if the ceiling joists are not working like rafter ties (as in, there is a seperate structural element holding up the rafters (structural ridge, etc)), but the ceiling joists are simply working like ceiling joists. That doesn't mean that one can neglect to attach the rafters to the top plate. Different discussion.

 

[STB]

Yankee is correct,

2009 IRC

Deleting the thrust factor at the rafter/celing joist connection by the installation of a structural ridge or supporting wall does not require the fastening schedule in 802.5.1(9), but you are still required by table 602.3(1) to connect the ceiling joist and rafters to the top plate with the required number of toe-nails. REMEMBER,, ""MINIMUM CRAP YOU CAN BUILD TO"".

I also believe there may be a typo in #3 of Table 602.3(1) by the addition of the word "not."

 

[PORTEOUS]

We have a city ordinance requiring a truss clip @ every other truss or rafter regardless of up-lift.

 

[TJacobs]

What Yankee and STB said...

 

[brudgers]

We have a city ordinance requiring a truss clip @ every other truss or rafter regardless of up-lift.

Just my opinion, but that's sort of silly since some truss clips provide less resistance than (3)16d.

Making a requirement not based on actual loads just seems like bad public policy, because it replaces proper design with a check box.

 

[PORTEOUS]

We do get alot of grief about that policy concidering a majority of truss up-lifts are less than nailing req., that does'nt mean we dont look @ up-lift on truss sheets. I find most gov. policys silly anyway, time to move to Jordan w/ the "freemen", an organization way before it's time! Bill

 

[brudgers]

We do get alot of grief about that policy concidering a majority of truss up-lifts are less than nailing req., that does'nt mean we dont look @ up-lift on truss sheets. I find most gov. policys silly anyway, time to move to Jordan w/ the "freemen", an organization way before it's time! Bill

Is it a policy or an actual ordinance?