| # | Company name | Role | # of projects |
|---|---|---|---|
| 681 | Whitecode Design Associates | MEP engineering | 7 |
| 682 | Whitney, Bailey, Cox & Magnani, LLC | MEP engineering | 3 |
| 683 | Wicotec A/S | MEP engineering | 0 |
| 684 | Wilson, Klaes, Brucker & Worden | MEP engineering | 1 |
| 685 | Winter Beratende Ingenieure für Gebäudetechnik GmbH | MEP engineering | 3 |
| 686 | Woowon M&E | MEP engineering | 4 |
| 687 | WSP | MEP engineering | 9 |
| 688 | WSP USA | MEP engineering | 7 |
| 689 | Wylie Consulting Engineers | MEP engineering | 41 |
| 690 | YIT Building Systems AS | MEP engineering | 5 |
| 691 | York Hunter Group | MEP engineering | 8 |
| 692 | Young's Engineering Holdings Limited | MEP engineering | 25 |
| 693 | Zibell, Willner + Partner | MEP engineering | 5 |
| 694 | ZPLAN HAUSTECHNIK GmbH | MEP engineering | 1 |