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Gregg Austensen
04-26-2007, 07:55 PM
Does anyone see an issue with this. The rafter were 2x8's and the ridge 2x6.

Jack Feldmann
04-26-2007, 08:31 PM
Gregg,
While this may not be "Inspector 101" it's pretty close and has been covered many times in this thread.

I hope that you called it out as a defect.
JF

BARRY ADAIR
04-26-2007, 08:45 PM
Yes the ridge is not the proper size and collar beams are also required unless they are present and out of the frame.
I looks like there is one back by the vent.

Richard Rushing
04-26-2007, 09:37 PM
Hello Gregg,

For future reference, here is the IRC back up for the requirement;

R802.3 Framing details. Rafters shall be framed to ridge board or to each other with a gusset plate as a tie. Ridge board shall be at least 1-inch (25.4 mm) nominal thickness and not less in depth than the cut end of the rafter. At all valleys and hips there shall be a valley or hip rafter not less than 2-inch (51mm) nominal thickness and not less in depth than the cut end of the rafter. Hip and valley rafters shall be supported at the ridge by a brace to a bearing partition or be designed to carry and distribute the specific load at that point. Where the roof pitch is less than three units vertical in 12 units horizontal (25-percent slope), structural members that support rafters and ceiling joists, such as ridge beams, hips and valleys, shall be designed as beams. installed to bearing walls at a slope not less than 45 degrees from the horizontal. The braces shall be spaced not more than 4 feet (1219 mm) on center and the unbraced length of braces shall not exceed 8 feet (2438 mm).

Hope this helps...

Rich

Chad Fabry
04-27-2007, 03:25 AM
Yes the ridge is not the proper size and collar beams are also required unless they are present and out of the frame.
I looks like there is one back by the vent.

Collar ties are required?

The ridge board isn't required, but if it's there it must be big enough to fully support the rafter.

Darren Miller
04-27-2007, 05:09 AM
Barry,

Coud you quote the section of the code that states collar ties are required?

According to the NJDCA (the board that oversees NJ code); collar ties are NOT required by code; the only time they are required is if they are part of the engineers design.


Darren

New Jersey Home Inspection - About the House! (http://www.aboutthehouseinspections.com)

Jerry Peck
04-27-2007, 06:00 AM
From the IRC.

(Tucked back in the wording of R802.3.1, just before R802.3.2.)


Collar ties or ridge straps to resist wind uplift shall be connected in the upper third of the attic space in accordance with Table R602.3(1).

Collar ties shall be a minimum of 1-inch by 4-inch (25 mm by 102 mm) (nominal), spaced not more than 4 feet (1219 mm) on center.

BARRY ADAIR
04-27-2007, 06:10 AM
Jerry,
Thanks!

Whew, that almost felt like I walked into a room full of builders going over one of my reports.

also from TREC SOP
(6) report as in need of repair the lack of or inappropriate installation of components such as purlins, struts, collar ties or rafter ties, where necessary

I was taught, back in the '70s by an Old World carpenter most of his plans were on a legal pad or napkin and designs were created on site, collar ties are required and therfore their absence in the subject photo would be noted as a repair in my report.

Richard Rushing
04-27-2007, 07:15 AM
Here is the whole enchilada:

2006 IRC: R802.3.1 Ceiling joist and rafter connections. Ceiling joists and rafters shall be nailed to each other in accordance with Table R802.5.1(9), and the rafter shall be nailed to the top wall plate in accordance with Table R602.3(1). Ceiling joists shall be continuous or securely joined in accordance with Table R802.5.1(9) where they meet over interior partitions and are nailed to adjacent rafters to provide a continuous tie across the building when such joists are parallel to the rafters. Where ceiling joists are not connected to the rafters at the top wall plate, joists connected higher in the attic shall be installed as rafter ties, or rafter ties shall be installed to provide a continuous tie. Where ceiling joists are not parallel to rafters, rafter ties shall be installed. Rafter ties shall be a minimum of 2-inch by 4-inch (51 mm by 102 mm) (nominal), installed in accordance with the connection requirements in Table R802.5.1(9), or connections of equivalent capacities shall be provided. Where ceiling joists or rafter ties are not provided, the ridge formed by these rafters shall be supported by a wall or girder designed in accordance with accepted engineering practice.Collar ties or ridge straps to resist wind uplift shall be connected in the upper third of the attic space in accordance with Table R602.3(1). Collar ties shall be a minimum of 1-inch by 4-inch (25 mm by 102 mm) (nominal), spaced not more than 4 feet (1219 mm) on center.

Darren Miller
04-27-2007, 10:03 AM
See that, just goes to show the difference is state requirements.

"Collar ties or ridge straps to resist wind uplift shall be connected in the upper third of the attic space in accordance with Table R602.3(1). Collar ties shall be a minimum of 1-inch by 4-inch (25 mm by 102 mm) (nominal), spaced not more than 4 feet (1219 mm) on center." does not appear in the NJ code.


"Where ceiling joists or rafter ties are not provided, the ridge formed by these rafters shall be supported by a wall or girder designed in accordance with accepted engineering practice." the next sentence states 'Rafter ties shall be spaced not more than 4 feet (1219) on center.' end of section.



Guess our wind isn't as strong as the rest of the country.


Darren
New Jersey Home Inspection - About the House! (http://www.aboutthehouseinspections.com)

Jerry Peck
04-27-2007, 11:13 AM
See that, just goes to show the difference is state requirements.

"Collar ties or ridge straps to resist wind uplift shall be connected in the upper third of the attic space in accordance with Table R602.3(1). Collar ties shall be a minimum of 1-inch by 4-inch (25 mm by 102 mm) (nominal), spaced not more than 4 feet (1219 mm) on center." does not appear in the NJ code.


"Where ceiling joists or rafter ties are not provided, the ridge formed by these rafters shall be supported by a wall or girder designed in accordance with accepted engineering practice." the next sentence states 'Rafter ties shall be spaced not more than 4 feet (1219) on center.' end of section.



Guess our wind isn't as strong as the rest of the country.


Darren

Actually, I think there is a wording recognition problem with the builders up there. :)

*I* *think* they are using the term "rafter ties" and are meaning "collar ties".

Are "rafter ties" defined in the NJ code? Does it say where the "rafter ties" are to be installed?


I'm going with 'they mean *collar* ties'.

Darren Miller
04-27-2007, 11:54 AM
"Where ceiling joists are not connected to the rafters at the top wall plate, joists connected higher in the attic shall be installed as rafter ties, or rafter ties shall be installed to provide a continuous tie. Where ceiling joists are not parallel to rafters, rafter ties shall be installed. Rafter ties shall be a minimum of 2-inch by 4-inch (51 mm by 102 mm) (nominal), installed in accordance with the connection requirements in Table R802.5.1(9), or connections of equivalent capacities shall be provided. Where ceiling joists or rafter ties are not provided, the ridge formed by these rafters shall be supported by a wall or girder designed in accordance with accepted engineering practice."

That's what the code says; obviously it defines rafter ties.

I just attended a NJDCA seminar on Framing Inspection and using a Checklist last week. That's how I know collar ties are not required here.

http://www.nj.gov/dca/codes/forms/pdf/framingchecklist.pdf

Here is the check list that all builders are required to fill out prior to calling for a framing inspection. He then hands the signed list to the building inspector and he conducts another inspection.

Darren

New Jersey Home Inspection - About the House! (http://www.aboutthehouseinspections.com)

Jerry Peck
04-27-2007, 06:54 PM
That's what the code says; obviously it defines rafter ties.

Actually, that does not define what a, nor state where a, "rafter tie" is or goes, other than "joists connected higher in the attic shall be installed as rafter ties".

How high, within the bottom third (a rater tie), within the middle third (a whatever), within the top third (a collar tie)?

Richard Rushing
04-27-2007, 08:11 PM
like this....


Rich

Darren Miller
04-28-2007, 04:47 AM
Actually in NJ it does:

"Where ceiling joists or rafter ties are not provided at the top plate, the ridge formed by these rafters shall be supported by a wall or girder designed in accordance with accepted engineering practice."

The words "at the top plate" are in our code books.

Darren

Jerry Peck
04-28-2007, 05:32 AM
Actually in NJ it does:

"Where ceiling joists or rafter ties are not provided at the top plate, the ridge formed by these rafters shall be supported by a wall or girder designed in accordance with accepted engineering practice."

The words "at the top plate" are in our code books.

Darren

No, that does not "define" "rafter ties", besides, you mis-quoted the section you provided, see below. (bold is mine)

"Where ceiling joists are not connected to the rafters at the top wall plate, joists connected higher in the attic shall be installed as rafter ties, or rafter ties shall be installed to provide a continuous tie. Where ceiling joists are not parallel to rafters, rafter ties shall be installed. Rafter ties shall be a minimum of 2-inch by 4-inch (51 mm by 102 mm) (nominal), installed in accordance with the connection requirements in Table R802.5.1(9), or connections of equivalent capacities shall be provided. Where ceiling joists or rafter ties are not provided, the ridge formed by these rafters shall be supported by a wall or girder designed in accordance with accepted engineering practice."

Darren, it's your code, but it does not say what you say it does, you are mixing parts of sentences with other parts of other sentences.

*IS* there "definition" for "rafter ties"?

Look in the definitions section. If your code is based on the ICC codes, that will be chapter 2, and Section 2 of other chapters.

Jerry McCarthy
04-30-2007, 04:54 PM
Darren
At the risk of sounding like a total "suck-up" listen to Jerry P as he has it right. He and I have had our disputes regarding code interpretations in the past, but this ain't one of them. If I had a nickle for every rafter tie somebody called a collar tie and visa-versa, deedle, deedle dum, da, da, dee....................! :D

Scott Patterson
04-30-2007, 09:41 PM
I have to agree with Jerry P. Another good point is that it is just good building practice.

I have also seen them referred to as Collar beams.

They tie the rafters and ridge together, reinforcing the roof frame and securing them against spreading outward.