Exhibit_C_Tier_1_Structual_Assessment.pdf

IRVINE • SACRAMENTO • SAN DIEGO • SAN JOSE • DALLAS • SAN ANTONIO

Date: April 3, 2026

Project Name: 750 Riverpoint FCA

Project No.: B33708

Regarding: Seismic Retrofit Study

1. 750 RIVERPOINT

1.1 EXISTING STRUCTURE

The two -story building at 750 Riverpo int was constructed in 1991 and comprises approximately 100,000 square feet. The lateral force -resisting system consists primarily of exterior concrete tilt -up panels along all sides of the building, supplemented in the transverse (north –south) direction by interior braced frames.

The roof structure is framed with untopped wood sheathing over dimensional lumber joists, supported by wood glulam beams spaced at approximately 8 feet on center. These beams frame into wood glulam girders, which are supported by steel columns arranged on an approximate 30 - foot by 32 - foot grid.

The second floor consists of 2½ - inch lightweight concrete placed over metal deck. The deck is supported by steel wide - flange beams at approximately 11 feet on center, which in turn frame into wide - flange girders spanning to steel columns.

The foundation system consists of cast - in -drilled -hole (CIDH) piles supporting the columns and the ends of the tilt -up wall panels.

750 Riverpoint I April 3, 2026 LPA Project No.: B33708 I Page 2

1.2 RECOMMENDATIONS

Note the site is located within a mapped liquefaction zone. Required mitigation measures may vary significantly and could result in substantial cost. A geotechnical engineer should be consulted to evaluate site conditions and determine whether ground improvement or other remediation measures are necessary .

Structural Retrofit (See exhibit for clarification )

▪ Provide full -height buckling restrained braced frames (BRBFs) at the indicated locations (4 bays total, 16 braces), including new steel wide - flange columns. At the roof level, provide a continuous line of steel beams along each frame line. At the second floor, str engthen existing steel beams and weld existing steel connections as required .

▪ Provide CIDH piles and pile caps at each BRBF column, interconnected with grade beams

▪ At all tilt -up wall panels, construct new reinforced concrete grade beams. Dowels shall be drilled and epoxied into the panels, and the new grade beams shall be drilled and epoxied into the existing concrete piles .

▪ Remove existing braced frames at fourteen (14) locations over the full height of the structure. Protect existing beams and columns during demolition .

2ND FLOOR

▪ At north entry, provide horizontal HSS at small narrow deck area .

▪ Provide (N) Wide flange bracing members to laterally brace the existing beams in line with the new braces. Provide a welded top plate with expansion anchors to the deck.

▪ Streng then existin g steel beams in the braced frame line with welded plates and/or WT members.

▪ Provide FRP at all tilt -up spandrels. FRP should extend for 8’ at each end of the spandrel s for the full height of the spandrel.

ROOF

▪ Provide straps and blocking as indicated along the north and south sides.

▪ Provide wall anchors and anchor plate s around full perimeter of building as indicated.

▪ In design ated area s , provide additional plywood sheathing on the underside of the roof joists.

▪ At bays receiving new BRBFs, remove and replace existing plywood sheathing as required to facilitate installation of new steel beams; replace roofing upon completion .

▪ Provide (N) Wide flange bracing beams along (N) steel frame beam lines.

▪ Provide hold downs across glulam beam supports as indicated.

▪ Provide straps each side of glulam girder splices/supports.

LPA Project No.: B33708 I Page 3

Non -structural Items

▪ Stairs .

Provide steel angles welded to stringers and expansion anchors into the slab -on - grade.

▪ MEP Equipment

Existing equipment will need to be evaluated based on product data to determine if achorage is adequate. Supplemental anchorage should be assumed.

Large (E) Mechanical Units

▪ MEP Distribution Systems

Existing Distribution Systems are assumed to be replaced and therefore do not require remediation.

▪ Elevators

An elevator contractor or inspector should be retained to provide review and recommendations for potential remedation for conversion to a Risk Category IV building.

▪ Masonry Veneer

Testing/Inspection will be required to verify if anchorage meets requirements for a Risk Category IV building. Existing veneer that shows indications of damage or does not meet requirements will need to be replacement.

▪ Additional Considerations

LPA Project No.: B33708 I Page 4

Material testing will be required for existing concrete, reinforcing steel, structural steel, and wood elements. The project should include allowances for destructive testing and subsequent repairs .

T he underside of the second floor and roof is finished with gypsum sheathing, likely for fire - resistance rating. It should be assumed that any areas impacted by structural work will require removal and replacement of this sheathing .

NOTES:

1. CONCRETE TO HAVE COMPRESSIVE STRENGTH, F'C, OF 4000 PSI

2. PROVIDE SHORING AS REQUIRED TO PROTECT (E) STRUCTURE

3. (E) CONC TO BE SCANNED PRIOR TO DRILL AND EPOXY TO AVOID (E) REBAR

NOTES:

1. CONCRETE TO HAVE COMPRESSIVE STRENGTH, F'C, OF 4000 PSI

2. PROVIDE SHORING AS REQUIRED TO PROTECT (E) STRUCTURE

3. (E) CONC TO BE SCANNED PRIOR TO DRILL AND EPOXY TO AVOID (E) REBAR

REMOVE (E) BRACES,

PROTECT (E)

BEAMS/COLUMNS,

TYP.

APPROXIMATE EXTENT OF DEMO

AND REPLACE OF (E) SOG - DRILL

AND EPOXY TO (E) SOG, TYP

APPROXIMATE EXTENT OF DEMO

AND REPLACE OF (E) SOG - DRILL

AND EPOXY TO (E) SOG, TYP

(N) FOOTING 3' SQ REINFORCED

GRADE BEAM W/ #5 DRILL &

EPOXY DOWELS @ 12' O/C TO (E)

PANEL, TYP AT PANELS

(N) FOOTING 3' SQ REINFORCED

GRADE BEAM W/ #5 DRILL &

EPOXY DOWELS @ 12' O/C TO (E)

PANEL, TYP AT ALL PANELS

(N) PILE CAP AND PILES, TYP

(N) GRADE BEAM, TYP

(N) WF COLUMN, TYP

(N) BUCKLING

RESTRAINED BRACES,

(2) PER BAY, TYP.

REMOVE (E) BRACES,

PROTECT (E)

BEAMS/COLUMNS, TYP.

(N) WF COL, TYP

(N) BUCKLING

RESTRAINED BRACES,

(2) PER BAY, TYP.

(N) WF BEAM,

TYP

(N) ADDED PLATES/WT

STRENGTHENING AT

(N)BRB FRAME LINES,

TYP.

WELD (E) SHEAR PLATES

TO BEAM ALONG (N) BRBF

LINES, TYP ALL BEAM CONN

(N) HSS HORIZONTAL

BRACING

B

BTYP

TYP

A TYP

A TYP

B

BTYP

TYP

A TYP

NOTES:

1. CONCRETE TO HAVE COMPRESSIVE STRENGTH, F'C, OF 4000 PSI

2. PROVIDE SHORING AS REQUIRED TO PROTECT (E) STRUCTURE

3. (E) CONC TO BE SCANNED PRIOR TO DRILL AND EPOXY TO AVOID (E) REBAR

(N) (2) HOLDDOWN

TIES, TYP.

(N) (2) WALL ANCHOR @

EA GLB THRU WALL W/

ANCHOR PLATE, TYP.

(N) WF STEEL BEAM W/

NAILER FULL WIDTH OF

BUILDING @ (N) BRB

FRAME LINES, TYP.

(N) WF STEEL BEAM

BRACING BEAM W/

NAILER @ (N) BRB

FRAME LINES, TYP.

AT BAY WITH (N) BRB FRAME,

REMOVE AND REPLACE

SHEATHING AT (N) STEEL

BEAMS, REPLACE ROOFING,

TYP.

AT HATCH, PROVIDE 1/2"

PLYWOOD SHEATHING @

UNDERSIDE OF 2x, BTWN

GLB FOR EXTEND SHOWN,

TYP.

(N) STRAP AS SHOWN,

PROVIDE 4X BLKG AS REQ'D

(N) STRAP AS SHOWN,

PROVIDE 4X BLKG AS REQ'D

(N) (2) WALL ANCHOR @

EA GLB THRU WALL W/

ANCHOR PLATE, TYP.

(N) (2) WALL ANCHOR @

8' O/C THRU WALL W/

ANCHOR PLATE, TYP.

(N) (2) WALL ANCHOR @

8' O/C THRU WALL W/

ANCHOR PLATE, TYP.

PROVIDE STRAP EACH SIDE

OF GIRDER AT SPLICE, TYP

B

B

BTYP

TYP

(E) PILE

(E) TILT-UP PANEL

(E) STEEL BEAM

(E) CONCRETE

FILLED DECK

(E) GLB BEAM

(E) PLYWOOD

SHEATHING

(E) PILE

(E) TILT-UP PANEL

(E) STEEL BEAM

(E) CONCRETE

FILLED DECK

(E) GLB BEAM

(E) PLYWOOD

SHEATHING

(N) WALL

ANCHOR EA SIDE

OF 4x BLKG

(N) FACEPLATE

(N) PLYWOOD

SHEATHING

WHERE

OCCURS

(N) ANCHORED FRP FOR 8

FEET BY FULL HEIGHT AT EA

END OF ALL SPANDRELS

(E) SOG

(N) REINFORCED

GRADE BEAM

(N) REINFORCED

SOG

(N) WALL

ANCHOR EA SIDE

OF GLB

(N) PLYWOOD

SHEATHING

WHERE

OCCURS

(N) ANCHORED FRP FOR 8

FEET BY FULL HEIGHT AT EA

END OF ALL SPANDRELS

(N) REINFORCED

GRADE BEAM

(N) REINFORCED

SOG

(N) FACEPLATE

(E) SOG

SECTION A SECTION B