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Where to find guidelines for porch roof construction?

C

cam100

Member
Joined
Oct 25, 2011
Messages
2
Location
Virginia Beach, VA
Hello all,

I'm new here, and have been learning a lot from reading through this forum. I am planning a long covered front porch (for my Virginia home) that I want to build using deck construction techniques. I am following the AWC Prescriptive Deck Guide, but it doesn't address roofs. I can't find anything in the IRC that specifically addresses them, either. Is there any publication that covers constructing porch roofs under the 2009 IRC?

Thanks!
 
Decks are floors - Roofs are roofs. When built as unenclosed spaces (Sans Exterior walls)

Uplift and wind forces are applied to top and bottom surfaces at the same time (like double but worse)

single story roofs agin a 2 story structure also have an increased snow loading factor - so most of prescriptive rafter charts require calculatiom.

WFCM or ASCE-7
 
Hi Cam,

ASCE-7 is a difficult to parse standard that is designed for engineers.

I suggest that you contact the local building department and ask them for some help. They may offer it, they may not, probably the former. There are a lot of factors to consider one of which is exposure category.

I'm bettin that a conversation with the local plans examiner will be very helpful.

Bill
 
cam welcome. What Bill invited is excellent adviced.

Contact Virginia Beach Gov for specific requirements if any on your location about flood elevations; wind speed of >110 mph in addition to Zoning setbacks and architectural review as this will have bearing on your construction.

The AWC (DCA6-09) is an excellent reference guide for decks, but is generic and there too may be local amendments made to the Virginia edition of the Uniform Statewide Building Code (USBC).

Respectfully not knowing your expertise and experience in residential construction I recommend contracting a local builder that could help you with this project might save some time and money in the long run.

Francis
 
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Agree with Francis, in my opinion code books and the WFCM are great for code reference and code application but not really meant as a how to guide. Lots of how to guides out there, including a pro. There are some high wind framing guides out there that you may want to look at as well. I believe APA or AWC just published a new one.
 
@KZQ my rule of thumb!

Never ask a building official (fire marshal, planner, zoning officer etc:)

what they want! It's like asking the used car salesman how much they want for the car!

and it makes them the designer...

keep in mind I r a designa an a inspecta.

When contractors ask me what I want, the answer is (you dont want that answer - inside my head)

but it sounds alot like - compliant construction I can approve....
 
Sifu (and others),

Do you have a link to the APA or AWc guides for porch / roof construction,

or is there another resource out there for us to use?

Thanks! :)
 
globe,

I know of no prescriptive covered porch guide that is recognized by the ICC. I design these using the Wood Frame Construction Manual by the American Wood Council. This is a referenced design standard as found in Section R301.2.1.1 of the 2009 IRC. The area I work in is a 110-mph wind speed in a hurricane-prone region. Fortunately it has been almost 21 years since our last hurricane.

May be if enough request this through the American Wood Council they will produce one similar to the DCA6 Prescriptive Residential Deck Construction Guide.
 
GBrackins said:
globe, I know of no prescriptive covered porch guide that is recognized by the ICC. I design these using the Wood Frame Construction Manual by the American Wood Council. This is a referenced design standard as found in Section R301.2.1.1 of the 2009 IRC. The area I work in is a 110-mph wind speed in a hurricane-prone region. Fortunately it has been almost 21 years since our last hurricane. May be if enough request this through the American Wood Council they will produce one similar to the DCA6 Prescriptive Residential Deck Construction Guide.
Click to expand...
ASCE-7 will work, of course. The old SSTD 10 is also a good resource.

The problem with porches is that they are partially enclosed.

Thus the windloads are significantly higher.
 
One important suggestion regarding roof construction is that never try to work on a roof without a scaffold. Tiles are constantly under the hammer from our weather and as such can be very slippery even on the driest of days.

____

roofing companies in vancouver
 
Cam,

I would start with the city's planning department first before doing anything due to some sub-divisions having a requirement called a buildline. A buildline is an imagainary line that you should not build a structure, usually set at over 30" above grade. If no sub-division rules, then it's a mute point.

pc1
 
Mr.Inspector said:
Here is a link to a "guide to building carports and patio roofs" from the Colorado Chapter of the ICC. I hand them out now and then to give folks the "general" idea of what is required of them when submitting a design for review.http://www.coloradochaptericc.org/patio-cover2k09.pdf

may or may not help with your situation.:cheers
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Francis Vineyard said:
Posted this link on another thread (now duplicated here) http://www.ci.bremerton.wa.us/forms/communitydev/permits/PorchCarport.pdfprovided as information, its accuracy has not been verified or endorsed by Francis
Click to expand...
Thank you, Francis Vineyard & Mr. Inspector. These types of prescriptive documents are what I was looking for.
 
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