Thread: minimum footing depth for patio cover

Does anyone know the minimum footing depth for a patio cover in San Jose, CA?

Thank you.

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Originally Posted by Steven Lim

Does anyone know the minimum footing depth for a patio cover in San Jose, CA?

Thank you.

Without knowing all the specifics see link http://www.sanjoseca.gov/DocumentCenter/View/977

18 inches is the very minimum.

The IRC likes to see either a 12" minimum, or below the frost line (not an issue in CA). They also defer to the local AHJ, so that would be the best source for a definitive answer.

Originally Posted by Billy Stephens

Without knowing all the specifics see link http://www.sanjoseca.gov/DocumentCenter/View/977

18 inches is the very minimum.

Originally Posted by BridgeMan

The IRC likes to see either a 12" minimum, or below the frost line (not an issue in CA). They also defer to the local AHJ, so that would be the best source for a definitive answer.

San Jose ( see link ) has an 18 inch Minimum.

Originally Posted by Billy Stephens

San Jose ( see link ) has an 18 inch Minimum.

The San Jose link furnished is for building foundations. I'm not sure a patio cover qualifies as "a building." But I'll bet the local AHJ would have the answer.

Originally Posted by BridgeMan

The San Jose link furnished is for building foundations. I'm not sure a patio cover qualifies as "a building." But I'll bet the local AHJ would have the answer.

Yes, the AHJ may have requirements like we have - if there is a footing present then it is presumed that the patio could be enclosed, therefore a full and proper footings is required.

Don't recall the OP specifying geo tech specifics, SFH, nor attached vs. detached Patio Cover. If multi-family, commercial, etc. the following citations/quotations does/do not apply:

Link to 2010 California Residential Code (with 2011 Amendments) clickable link: State

Link to San Jose, CA Municipal Codes, Title 24 (clickable link, navigate within to Residential Code (24.09): American Legal Publishing - Online Library

Note ordinances updated subsequent to a prior poster's document which refers to outdated state codes.

From the San Jose Municipal Codes, Title 24:

24.09.100 Adoption of technical provisions of California Residential Code.

A. Except as otherwise provided for in this chapter, the California Residential Code, 2010 edition, including the appendices thereto, together with those omissions, amendments, exceptions and additions thereto as amended in Title 24 of the California Code of Regulations are approved and adopted, and are hereby incorporated in this chapter by reference and made a part hereof the same as if fully set forth herein.

B. One copy of the CRC has been filed for use and examination of the public in the Office of the City Clerk of the City of San José.
(Ord. 28838.)

24.09.110 Portions of California Residential Code which are not approved, adopted or incorported by reference.

A. The following portions of the "California Residential Code, 2010 edition," are not approved or adopted or incorporated in this chapter by reference, and shall not be deemed to be a part of this chapter nor a part of the residential code of the City of San José:

1. Section 1.8.3
2. Section 1.8.4
3. Section 1.8.5
4. Section 1.8.6
5. Section 1.8.7
6. Section 1.8.8
7. Chapter 1, Division II

B. The following appendices are adopted:

1. Appendix E; Manufactured Housing Used as Dwelling (excluding Sections AE101 through AE 307).
2. Appendix G; Swimming Pools, Spas and Hot Tubs.
3. Appendix H; Patio Covers.
4. Appendix K; Sound Transmission.

From the California Residential Code, 2010 edition (Apendix H, from the link to same provided earlier - above):

Section AH106 FOOTINGS

AH106.1 General. In areas with a frostline depth of zero as specified in Table R301.2(1), a patio cover shall be permitted to be supported on a slab on grade without footings, provided the slab conforms to the provisions of Section R506 of this code, is not less than 3.5 inches (89 mm) thick and the columns do not support live and dead loads in excess of 750 pounds (3.34 kN) per column.

Note from Chapter 4, 2010 CRC:

R407.3 Structural requirements. The columns shall be restrained to prevent lateral displacement at the bottom end. Wood columns shall not be less in nominal size than 4 inches by 4 inches (102 mm by 102 mm). Steel columns shall not be less than 3-inch-diameter (76 mm) Schedule 40 pipe manufactured in accordance with ASTM A 53 Grade B or approved equivalent.)

Also from the 2010 California Residential Code, Appendix H:

SECTION AH102 DEFINITION (Patio Covers):


Patio covers. One-story structures not exceeding 12 feet (3657 mm) in height. Enclosure walls shall be permitted to be of any configuration, provided the open or glazed area of the longer wall and one additional wall is equal to at least 65 percent of the area below a minimum of 6 feet 8 inches (2032 mm) of each wall, measured from the floor. Openings shall be permitted to be enclosed with (1) insect screening, (2) approved translucent or transparent plastic not more than 0.125 inch (3.2 mm) in thickness, (3) glass conforming to the provisions of Section R308, or (4) any combination of the foregoing.

Back to the San Jose Muni Codes, TItle 24, Residential Code (24.09, from Link provided earlier above)::

24.09.310 Findings.

The amendment set forth in Parts 1 and 2 of this chapter is reasonably necessary because of the following local geological and topographical conditions:

A. San José is within a very active seismic area.

B. Gypsum wallboard and exterior Portland cement plaster have performed poorly during recent California seismic events.

C. The shear values for gypsum wallboard and Portland cement stucco contained on the code are based on monodirectional testing.

D. The limitation on the use of these systems as set forth in the amendment until cyclic loading testing are performed and evaluated is a more restrictive standard which will better prevent damage which can result from local conditions.

(Ord. 28838.)

24.09.320 Seismic Reinforcing (CRC Section R403.1.3)

CRC Section 403.1.3 is amended to read as follows:

R403.1.3 Seismic reinforcing. Concrete footings located in Seismic Design Categories D0, D1, D2, as established in Table R301.2 (1), shall have minimum reinforcement. Bottom reinforcement shall be located a minimum of 3 inches (76 mm) clear from the bottom of the footing.

In Seismic Design Categories D0, D1 and D2 where a construction joint is created between a concrete footing and a stem wall, a minimum of one No.4 bar shall be installed at not more than 4 feet (1219 mm) on center. The vertical bar shall extend to 3 inches (76mm) clear of the bottom of the footing, have a standard hook and extend a minimum of 14 inches (357 mm) into the stem wall.

In Seismic Design Categories D0, D1 and D2 where a grouted masonry stem wall is supported on a concrete footing and stem wall, a minimum of one No. 4 bar shall be installed at not more than 4 feet (1219mm) on center. The vertical bar shall extend to 3 inches (76 mm) clear of the bottom of the footing and have a standard hook.

In Seismic Design Categories D0, D1 and D2 masonry stem walls without solid grout and vertical reinforcing are not permitted.
(Ord. 28838.)

24.09.330 Wall Bracing (CRC Section R602.10 Table 602.10.1.2(2)).

CRC Section R602.10 Table R602.10.1.2(2) is mended to read as follows:

See link provided above to muni code Title 24, link to Residential Code, scroll down to Chpter 24.09 subsection, if applicable.



HTH

As others have mentioned, best is to ask the AHJ. Back when I was building in California, just up the road in Vallejo, the AHJ had us install 12x12 footings for a patio cover.

As Watson depicted 0" for a patio -BUT if there is any anticipated use other than a patio in the future now is the time to accommodate that.

No footings required for a patio, driveway, or sidewalk around here. That would be kinda silly.

Originally Posted by Joe Funderburk

No footings required for a patio, driveway, or sidewalk around here. That would be kinda silly.

Guessing you missed the "Cover" part of "Patio Cover".

High wind areas/hurricane zones, and BTW there ARE some "D" zones EVEN in NC/SC. Depends on topography, geo, and seismic as well as frost/freeze lines in addition to the size, loads, & method of construction, detached, attached, etc.

The OP (hailing from San Jose, California - i.e. an area known for significant SEISMIC activity) regarding Patio COVER was NOT SILLY, far from it. The OP also did not indicate if said "Patio" is a slab (could be paver bricks permiable/perk-able bedding, for example), nor if slab if is conforming.

Originally Posted by H.G. Watson, Sr.

Guessing you missed the "Cover" part of "Patio Cover".

High wind areas/hurricane zones, and BTW there ARE some "D" zones EVEN in NC/SC. Depends on topography, geo, and seismic as well as frost/freeze lines in addition to the size, loads, & method of construction, detached, attached, etc.

The OP (hailing from San Jose, California - i.e. an area known for significant SEISMIC activity) regarding Patio COVER was NOT SILLY, far from it. The OP also did not indicate if said "Patio" is a slab (could be paver bricks permiable/perk-able bedding, for example), nor if slab if is conforming.

I did miss it. But if the "patio cover" is not a structural or permanent part of the house, then no footing would be warranted in my view.

Originally Posted by Joe Funderburk

I did miss it. But if the "patio cover" is not a structural or permanent part of the house, then no footing would be warranted in my view.

Footer for the support post/column for cover/roof.

Originally Posted by Joe Funderburk

I did miss it. But if the "patio cover" is not a structural or permanent part of the house, then no footing would be warranted in my view.

Originally Posted by Garry Sorrells

Footer for the support post/column for cover/roof.

Garry is correct - even if the patio is "detached" from the house and the "patio cover" is not a structural or permanent part of the house, it is itself a "structure" by definition, it is also a "building" by definition, and a footing is required to the extent stated in the applicable code for that type/style of building/structure.

If the "patio cover" was "attached" to the house, it would still require supporting posts at the two outboard corners, and, depending on the live loads, beam size between those two support posts, additional support posts may be required; each support post would require a footing designed in accordance with code requirements or by an engineer - which should also meet code requirements, but being an engineer and the fact that they sign and seal their plans, fuzzy stuff gets signed off, and if not fuzzy enough to trigger 'this just does not look right', it gets approved based on being signed and sealed by the engineer. That said, though, we find engineered drawings which do not match the requirements of those same engineered drawings - everyone makes errors at one time or another.

I agree that anyone can make mistakes. Does make me wonder, though--I wonder how many professional engineers signed off on and stamped their seals on the plans for "Galloping Gertie" over the Tacoma Narrows before construction started?

In Maryland, depending on the county, the patio cover/roof columns require footers (usually) depending on the cover design and materials. If the patio is to be enclosed then the walls have to have footers. So, trying to use an existing slab can become a problem if you pull a permit that has walls in the original design. Attached to the house or not.

Originally Posted by Jerry Peck

Garry is correct - even if the patio is "detached" from the house and the "patio cover" is not a structural or permanent part of the house, it is itself a "structure" by definition, it is also a "building" by definition, and a footing is required to the extent stated in the applicable code for that type/style of building/structure.

If the "patio cover" was "attached" to the house, it would still require supporting posts at the two outboard corners, and, depending on the live loads, beam size between those two support posts, additional support posts may be required; each support post would require a footing designed in accordance with code requirements or by an engineer - which should also meet code requirements, but being an engineer and the fact that they sign and seal their plans, fuzzy stuff gets signed off, and if not fuzzy enough to trigger 'this just does not look right', it gets approved based on being signed and sealed by the engineer. That said, though, we find engineered drawings which do not match the requirements of those same engineered drawings - everyone makes errors at one time or another.

Bottom left photo is a patio cover attached to the house. A structure by definition?

http://www.google.com/url?sa=i&rct=j...62501522538493

Originally Posted by Joe Funderburk

A structure by definition?

Yes. It is also a "building" by definition. However, being attached makes it not a separate structure/building, it makes it part of the structure/building it is attached to.