| Jg Home Improvement INC | Jonathan Greg Rodriguez Pacheco | — | (510) 566 2984 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| Jh Construction | Zheng Guoyong | — | (408) 888 0115 | GC, remodel, ADU | Fremont · Alameda County | — | — |
| Jhd Construction INC | Du Jiang | — | (650) 305 1902 | GC, remodel, ADU | Newark · Alameda County | — | — |
| Jhr Framing | Romel Alvarado-Flores | — | (510) 967 1012 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| Jht Construction Services INC | James Pacheco Jr Silva | — | (510) 755 1914 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| Jia Mei Construction INC | Ai Houfu | — | (510) 676 8428 | GC, remodel, ADU | Fremont · Alameda County | — | — |
| Jiahao Yang | Jiahao Yang | jy2154@bath.ac.uk | (650) 200 6428 | GC, remodel, ADU | San Leandro · Alameda County | — | — |
| Jianhe Wu Electric | Wu Jianhe | — | (510) 424 4592 | Electricians | Oakland · Alameda County | — | — |
| Jiawen Construction | Chen Jiawen | — | (510) 328 5696 | GC, remodel, ADU | Alameda · Alameda County | — | — |
| Jic Construction | John Gregory Jr Hussey | — | (415) 933 6244 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Jie Liang Construction Co | Li Jie-liang | — | (510) 282 3306 | GC, remodel, ADU | San Leandro · Alameda County | — | — |
| Jifco INC | Jay Sumner Jr Forni | — | (925) 449 4665 | Other | Livermore · Alameda County | — | — |
| Jigsaw Restoration LLC | Hai Ngoc Vu | — | (408) 312 1487 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| Jim Gardner Construction INC | James Eugene Gardner | jim@jimgardnerconstruction.com | (510) 655 3409 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Jim Link Landscapes | Jim Link Landscapes | — | (415) 412 8906 | Windows, patio, painters | Oakland · Alameda County | — | — |
| Jim Moore | Jim Moore | — | (510) 655 6750 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Jim Van Boven General Contractor | Jim Van Boven General Contractor | — | (510) 301 4486 | GC, remodel, ADU | Berkeley · Alameda County | — | — |
| Jim's Glass | Jim's Glass | — | (925) 455 1235 | Windows, patio, painters | Livermore · Alameda County | — | — |
| Jim's Screen Machine INC | James Theofanopoulos | — | (925) 443 9981 | Other | Livermore · Alameda County | — | — |
| Jimco Building Service | James Andrew Yunker | — | (925) 548 0084 | GC, remodel, ADU | Livermore · Alameda County | — | — |
| Jimenez Glass | Jimenez Glass | — | (510) 467 2474 | Windows, patio, painters | San Leandro · Alameda County | — | — |
| Jimmy Carl Duarte Electric | Jimmy Carl Duarte | — | (415) 716 4776 | Electricians | San Leandro · Alameda County | — | — |
| Jimmy Ho | Jimmy Ho | — | (510) 415 4994 | Windows, patio, painters | San Leandro · Alameda County | — | — |
| Jing Zhang | Jing Zhang | jim1981@foxmail.com | (415) 860 3518 | GC, remodel, ADU | Castro Valley · Alameda County | — | — |
| Jingharng Luo | Jingharng Luo | — | (408) 893 8938 | GC, remodel, ADU | Fremont · Alameda County | — | — |
| Jingjia Ren | Jingjia Ren | — | (571) 665 9522 | Electricians | Fremont · Alameda County | — | — |
| Jinhua Construction Company | Li Jinhua | — | (510) 338 8648 | GC, remodel, ADU | San Leandro · Alameda County | — | — |
| Jinsong Wang | Jinsong Wang | — | (925) 366 6888 | GC, remodel, ADU | Pleasanton · Alameda County | — | — |
| Jinxin Zheng | Jinxin Zheng | — | (646) 842 2192 | GC, remodel, ADU | Dublin · Alameda County | — | — |
| Jj Arias Home Remodel | Jj Arias Home Remodel | — | (415) 942 4749 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| Jj Construction & Home Improvment INC | Jose Juan Hernandez | — | (510) 910 0497 | GC, remodel, ADU | San Leandro · Alameda County | — | — |
| Jj Design Build | Jun Hai Chen | — | (415) 558 0338 | GC, remodel, ADU | San Leandro · Alameda County | — | — |
| Jjc Remodeling And Maintenance | Juan Jose Chan | — | (510) 904 2103 | Electricians | Oakland · Alameda County | — | — |
| Jk One-stop Construction INC | Yun Shen Guo | — | (510) 709 8391 | GC, remodel, ADU | Fremont · Alameda County | — | — |
| Jk Painting | Jk Painting | — | (510) 882 3132 | Windows, patio, painters | Castro Valley · Alameda County | — | — |
| Jk Painting Co | Min Jay Kang | — | (510) 673 1355 | Windows, patio, painters | Castro Valley · Alameda County | — | — |
| Jkl-bbi | K L Construction J | — | (510) 286 8210 | GC, remodel, ADU | Oakland · Alameda County | — | — |
| Jl Pro Construction LLC | Xiaodong Liang | — | (510) 830 6281 | GC, remodel, ADU | San Leandro · Alameda County | — | — |
| Jlb Builders & Millwork INC | Jose Luis Barradas | — | (650) 346 3710 | GC, remodel, ADU | Hayward · Alameda County | — | — |
| Jlb Constructors INC | Mercedes Angelelli Allende | — | (408) 461 1069 | GC, remodel, ADU | Hayward · Alameda County | — | — |