The code changes noted below are incorporated within the 2006 Virginia Uniform Statewide Building Code and the 2006 International Residential Code. Please note that this is not a complete list of changes but are changes that effect residential plan review. The effective date of this code is May 1, 2008.
Note that section 103.2 of the 2006 VUSBC provides a one-year period during which permit applicants may choose whether to comply with the provisions of the 2006 VUSBC or the VUSBC that is currently in effect (2003 VUSBC). The permit applicant must designate on the permit application whether they are invoking the option to use the 2003 USBC.
R202: Fire separation distance - The distance measured from the building face to one of the following:
1. To the closest interior lot line: or
2. To the centerline of a street, an alley or public way: or
3. To an imaginary line between two buildings on a lot.
R202: Thermal isolation- Physical or space conditioning separation from conditioned spaces. The conditioned spaces shall be controlled as separate zones for heating and cooling or conditioned by separate equipment.
V.U.S.B.C. change to R202: Story above grade - Any story having its finished floor surface above grade, except that a basement will be considered as a story above grade where the finished surface of the floor above the basement meets any one of the following:
1. Is more than 6 feet above the grade plane.
2. Is more than 6 feet above the finished grade level for more than 50% of the total building perimeter.
3. Is more than 12 feet above the finished ground level at any point.
*Roofed in floor areas (that have the headroom to be finished in the future) will be considered a story above grade unless the finishable floor area meets the definition of a mezzanine. A mezzanine is defined as a floor area that is 1/3 or less of the individual room or space it serves below.
R301.5: This section provides revised definitions for "attic spaces with limited storage" and "attic spaces without storage" that are to be used for either stick-framed or truss roof situations, which can be found in footnotes b and g of Table R301.5 (Essentially, attic areas greater than 42" in height need to be designed for 20 psf live load. Attic areas less than 42" in height can be designed for 10-psf live load). Also, footnote h states that any attic space, which is served by a fixed stair, must be designed for the minimum live load for sleeping rooms (30-psf live).
Attics with headroom that allows the space to be finished in the future will be required to be designed with a 40-psf live load unless a future finished floor plan is submitted detailing the intended use of the room as a bedroom.
V.U.S.B.C. change to R302.1: The section uses much of the old verbiage from IRC2003 R302.1 and applies it into a new table (Table R302.1). The table provides minimum fire separation distances of exterior wall elements and any fire-resistance rating required for that element. A new clarification is added to this section, which states that the provisions of the section shall not apply to walls, projections, openings, or penetrations in walls that are perpendicular to the line used to determine the fire separation distance. The section also clarifies that foundation vents (installed in compliance with the code) are permitted in foundation walls regardless of the wall's location to the minimum fire separation distance.
R303.1 Exception 3: This section allows a sunroom addition or patio cover to be used for the required natural ventilation into a habitable room provided that more than 40% of the exterior sunroom walls are open or are enclosed with insect screening.
R303.7.2: This section allows the required glazed opening in a habitable room to be permitted to open into a sunroom addition or patio cover abutting a street, yard, or court provided that more than 40% of the exterior sunroom walls are open or are enclosed with insect screening, and that the ceiling height of the sunroom is not less than 7 feet.
R308.4: Exception #4: The section now requires the glazing to be tempered in a wall that is perpendicular to the plane of a door, provided that the door swings toward the wall containing the glazing. This is only for swinging doors and the glass must be within a 24" arc of the door in a closed position.
Exception #9.3: Safety glazing adjacent to stairways, landings and ramps (noted in #10 and #11) are not required where a solid wall or panel extends to 34" to 36" above the floor.
V.U.S.B.C. change to R310.1: The section clarifies that the operable emergency escape and rescue openings that are required for basements must open up to a street, alley, yard or court (and not into another room in the basement). However, an escape/rescue opening is not required for basements that house mechanical equipment and that do not exceed 200 square feet. The section also allows emergency escape windows to be located under decks and porches (provided that the window can be fully opened and a path of not less than 36" in height can be provided to a yard or court). Exception: Dwelling units equipped throughout with an approved automatic sprinkler system.
V.U.S.B.C. change to R311.5.3.1 - The maximum stair riser height shall be 8-1/4".
V.U.S.B.C. change to R311.5.3.2 - The minimum stair tread depth shall be 9".
R311.5.4: The section clarifies that a landing is not required at the top of a stair in an enclosed garage (provided that the door does not swing over the stair).
R311.6.1: The section now limits the slopes of ramps to one unit vertical per twelve units horizontal (Except where it is technically infeasible due to site constraints, one unit vertical per eight units horizontal is permitted).
R314.5.4: Foam plastic insulation installed on perimeter walls of ventless crawl spaces shall be covered with one of the ignition barrier materials as specified in code section R3214.5.4; unless specifically approved in code section R314.6 by the following approved tests: NFPA 286, FM4880, UL1040 or UL 1715 or fire tests related to actual end-use configurations. Specific manufacturer's test report and/or installation instructions shall be attached to the building permit application plans. All conditions of use listed within independent test report shall be complied with.
Note: See IRC code section R408.3 for the three ventilation options for unvented crawl spaces.
R323: This new section provides the standards by which elevators and platform lifts are to comply with.
The 2006 V.U.S.B.C. deletes all basement wall to floor framing connection details that were added to the 2006 IRC code. Tables R404.1(1), R404.1(2) and R404.1(3) are deleted.
R408.3 Unvented Crawl Spaces: This code section gives the builder three options to choose from regarding required supply and/or return air in an unvented crawl space.
1. Continuously operated mechanical exhaust ventilation at a rate equal to 1 cfm for each 50 sq. ft. of crawl space floor area, including an air pathway to the common area above, or
2. Conditioned air supply sized to deliver at a rate equal to 1 cfm for each 50 sq. ft. of crawl space floor area, including a return air pathway to the common area above, or
3. Comply with section M1601.4 if the under-floor space is used as a plenum
*Your choice of one of these options shall be noted on the permit application plans.
*Note that most foam / polystyrene insulation boards are no longer allowed to left exposed in crawl spaces per the "conditions of use" specifications within the specific manufacturer's test report and IRC section R314.5.4, which requires an ignition barrier.
R502.1.6: Addresses use of structural log members in floor systems. - Requires grade mark or certificate of inspection for logs. Not necessary to address for our plan review.
R502.2.1: Requires a load path for lateral forces of interior braced wall lines at the floor and ceiling lines similar to what we have been requiring. We will look for this detail on the plans or attach a copy of this detail from the "Easy Read Wall Bracing Brochure".
R502.7: Now requires a "full-depth header" for supporting joists. Previously did not require it to be full-depth.
R502.11.2: Truss bracing - update reference from TPI H1B to "BCSI 1-03", which is the predecessor to the BCSI Guide to Good Practice for Handling, Installing, Restraining & Bracing of Metal Plate Connected Wood Trusses that we have been using. We require one copy of the BCSI B3 summary sheet be attached to the field copy of the truss plans.
R506.2.4: This section was added to require reinforcement in slabs to be supported so that it will remain in place from the center to upper one third of the slab for the duration of the concrete placement. This does affect plan review. We probably need to have a stamp made.
R602.1.3 Structural log members: Requires structural log members to be grade marked or certified as to species and grade.
Table R602.3(5): This table requires 2x6's 16" o.c. where the bearing wall framing supports "two stories and a roof and ceiling". This includes the exterior bearing wall framing on the first story of houses that support a second story and room trusses or finishable attic area above. (See note defining roofed-in finishable floor areas in R202).
R602.10: All wall bracing requirements of this section has been replaced by the 2006 Virginia Uniform Statewide Building Code replacement code section commonly called "EZ READ" wall bracing. It is strongly recommended that you obtain a copy of the 2006 V.U.S.B.C. and become familiar with these changes.
Notable changes include:
R602.10.1.1: Maximum spacing of parallel braced wall lines shall not exceed 50'.
R602.10.1.2: Mixing of braced wall methods is allowed within each story and braced wall lines.
R602.10.3.3: Individual continuous OSB braced wall lines shall have 24" OSB returns on perpendicular walls or be anchored to the foundation at corners with a minimum 800-lb. hold down device. You may continue to provide whole house continuous OSB sheathing per R602.10.5 without hold-down devices.
R602.10.5: Wall section details are provided for tying interior braced wall panels to the floor above and below the individual panel.
R602.10.6: All masonry stem walls that are 48" or less in width below braced wall panels shall be built with a bond beam and be reinforced per the options noted in figure R602.10.6.
*Code compliant wall bracing details are required to be noted on the plans submitted for building permit application. This includes marking the location of all braced wall lines and braced wall panels on the individual floor plans and detailing any required bond beam on the foundation plan. Please specify the material used for all braced wall panels on all braced wall lines where intermittent bracing panels are utilized. (Individual panels on braced wall lines do not have to be identified where continuous OSB sheathing is installed on the entire perimeter of the house).
R604.4 Support Conditions: Changes this from a sub-section of corbelled masonry to a general requirement for all masonry.
R613.2 Window sills: Where the opening of a window is located more than 72 inches above the exterior finished grade or surface below, the lowest part of the window's clear opening must be a minimum of 18 inches above the finished floor of the room where the window is located. Glazing between the floor and 18 inches shall be fixed or have openings such that a 4-inch diameter sphere cannot pass through. Window guards, if installed, shall comply with ASTM F 2006 for non-egress applications and ASTM F 2090 for emergency escape bedroom windows.
R703.2 Water-resistive barrier: Requires that 15lb.felt "or other water-resistive barrier" (e.g., asphalt impregnated sheathing, foam plastic sheathing) be applied over studs or sheathing of all exterior walls except for detached accessory buildings, as permitted by table R703.4, and under weather-resistive paperbacked stucco lathe.
Table 703.4 Weather-resistant siding attachment and minimum thickness: Primary change is to revise the response to "YES" for all materials in the column labeled Water-Resistive Barrier Required. Adds footnote z concerning adhered masonry and referencing Sections 6.1 and 6.3 of ACI 530.
R703.7 Stone and masonry veneer, general: These changes took what was a longer list of exceptions and converted them into Table R703.7 (1). Provides height limitations for stone veneer supported by a foundation within seismic category "B" for Henrico County. New language in the revised exceptions stipulates that bracing shall comply with R602.10 for wood framed dwellings. *Manufacturer's installation instructions shall be attached to the approved plans for adhered masonry veneer.
Figures R703.7 Masonry Wall Details: Revises the illustrations to add call outs for "water resistive barrier or approved water-repellant sheathing".
R802.3.1: Collar ties or ridge straps are required to resist ridge uplift in the upper 1/3 of the attic space. Collar ties shall be minimum 1x4's or 1 " x 20 gage ridge straps spaced 48" o.c. maximum. Nailing shall be 3-10d nails. (42" height clearance rule)
Table 802.5.1(1) - (8): Rafter span tables allow the ceiling joist to be raised up a maximum 1/3 the height of the roof and denote a rafter span reduction factor.
R802.7.2: Engineered wood products. Cuts, notches and bored holes are prohibited in engineered products except as permitted by the manufacturer's recommendations or by engineered design.
V.U.S.B.C. change to R806.4: This new section allows unvented conditioned attic assemblies where no vapor barrier is installed at the ceiling line and an air-impermeable and/or permeable insulation is installed between rafters. The insulation shall be installed per the manufacturer's specifications with a minimum R- 38 per table N1102.1 (R-30 for uncompressed insulation per exception in R1102.2.1). An independent test report is usually required for spray-on type foam plastic insulation where left exposed to the attic space per R314.5.3.
Insulation Options
a. Air-impermeable insulation only.
b. Air-permeable insulation only. In addition, rigid board or sheet insulation shall be installed over the roof sheathing.
c. Air-impermeable and air-permeable insulation.
Note: This insulation contributes to but does not supersede Chapter 11 energy requirements.
No plan review changes.
R1001.11 Note: A minimum 4" clearance is required for framing at the back of a fireplace up to the floor level above.
R1101.2 Compliance: Henrico County is in new climate zone #4A for use of table N1102.1 for insulation and fenestration requirements.
N1102.2.1 Ceilings with attic spaces: R-30 shall be deemed to satisfy the requirement for R-38 wherever the full height of uncompressed R-30 insulation extends over the wall top plate at the eaves.
N1102.2 Ceilings without attic spaces: When the design of the roof/ceiling assembly does not allow sufficient space for R-38 insulation, the minimum required insulation for such roof/ceiling assemblies shall be R-30. This reduction of insulation shall be limited to 500 sq. ft. of ceiling area.
Table N1102.1 Noted insulation requirement changes:
Fenestration U-factor = .40 (windows and doors)
Ceiling R-value = R-38 per notes above
Basement walls = R-10 for continuous blankets and R-13 for stud cavity
Slab = R-10
Crawl space walls = R-10 for continuous blankets and R-13 for stud cavity
N1102.2.7 Slab-on-grade floors: Slab-on-grade floors with a floor surface less than 12" below grade shall be insulated.
N1102.2.8 Ventless crawl space walls: Crawl space wall insulation shall extend down from the top of the masonry wall. The 1-1/2" sill plate may be left exposed as a termite inspection area. All joints of the vapor retarder shall overlap 6" and be sealed or taped. The edges of the vapor retarder shall extend at least 6" up the stem wall and be attached to the wall.
N1102.2.10 Thermally isolated sunroom insulation: Thermally isolated sunrooms that are heated may have R-19 insulation in the ceiling. Elevated floors exposed to outside elements require R-19 minimum.
N1102.5 Exception #2 Moisture control: Walls, floors and ceilings are not required to have a vapor barrier installed on the warm-in-winter side of the insulation.
Notice: The footing steel rebar shall be grounded to the house electrical system.