Company lists · Data refreshed October 2026

Top 18 Hvac design engineering firms based in Seattle, United States

Name: Hvac design engineering firms based in Seattle, United States
Creator: RevenueBase
License: https://creativecommons.org/licenses/by/4.0/

Compiled by the RevenueBase Data Team Data refreshed Oct 14, 2026 29 companies tracked

RevenueBase identified 29 company matches for hvac design engineering firms associated with Seattle, United States as of October 2026 and tracks 823 professional contacts across them, including 542 with verified work emails. Across the United States, New York is the largest hub for this category (182 companies); Seattle has 29.

This list covers company matches for hvac design engineering firms associated with Seattle, United States, found by RevenueBase SmartSearch using the meaning of business descriptions in its company graph at Exact. Ranked by professionals tracked, largest first. Rows show recorded descriptions where available, Exact search membership and the snapshot date. Data refreshed October 14, 2026.

Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase SmartSearch, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.

How to read this list RevenueBase SmartSearch · Exact Recorded Oct 14, 2026 How this list was built

29Companies

823Contacts tracked

542Verified emails

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The 18 largest hvac design engineering firms based in Seattle, United States

Ranked by team size

Top 18 of 29 company matches for hvac design engineering firms based in Seattle, United States, ordered by professional contacts tracked in RevenueBase, largest first. Recorded Oct 14, 2026. The RevenueBase SmartSearch column shows Exact match membership in this saved search. Click a contact count to view that company's people. Totals use company locations recorded by RevenueBase; the displayed preview is a smaller selection.
#	Company	RevenueBase SmartSearch	Headquarters	Employees	Contacts
1	Hargis Engineers	Exact match	Seattle, WA, United StatesHQ recorded Oct 14, 2026	201-500	192 contacts →
	Exact match “Hargis Engineers is a mechanical, electrical, telecommunications, security, energy consulting engineering, and commissioning firm.” Recorded in the RevenueBase company graph · Oct 14, 2026 · View company records in RevenueBase
2	Säzän Group INC	Exact match	Seattle, WA, United StatesHQ recorded Oct 14, 2026	51-200	158 contacts →
	Exact match “Säzän Group is an engineering and consulting firm with offices in Washington, Oregon, and Arizona.” Recorded in the RevenueBase company graph · Oct 14, 2026 · View company records in RevenueBase
3	ACI Mechanical & Hvac Sales	Exact match	Seattle, WA, United StatesHQ recorded Oct 14, 2026	51-200	83 contacts →
	Exact match “ACI is the Pacific Northwest's vendor of choice for heating, ventilation, air distribution and filtration equipment since 1985.” Recorded in the RevenueBase company graph · Oct 14, 2026 · View company records in RevenueBase
4	ABKJ	Exact match	Seattle, WA, United StatesHQ recorded Oct 14, 2026	11-50	67 contacts →
	Exact match “Andersen Bjornstad Kane Jacobs (ABKJ) is a premier consulting design firm in the United States.” Recorded in the RevenueBase company graph · Oct 14, 2026 · View company records in RevenueBase
5	FSI Engineers	Exact match	Seattle, WA, United StatesHQ recorded Oct 14, 2026	11-50	47 contacts →
	Exact match “Founded in 1985, FSi Engineers provides a full range of MEP and fire protection engineering services clients from the Pacific Northwest to the Mid-Atlantic region.” Recorded in the RevenueBase company graph · Oct 14, 2026 · View company records in RevenueBase
6	Swenson SAY Faget	Exact match	Seattle, WA, United StatesHQ recorded Oct 14, 2026	51-200	46 contacts →
	Exact match “At Swenson Say Faget, our team of structural engineers is committed to finding the right design solutions.” Recorded in the RevenueBase company graph · Oct 14, 2026 · View company records in RevenueBase
7	Neudorfer Engineers, LLC	Exact match	Seattle, WA, United StatesHQ recorded Oct 14, 2026	51-200	45 contacts →
	Exact match “Neudorfer Engineers is an integrated, multi-disciplinary firm with experts in a variety of project types.” Recorded in the RevenueBase company graph · Oct 14, 2026 · View company records in RevenueBase
8	Mechanical Sales, INC	Exact match	Seattle, WA, United StatesHQ recorded Oct 14, 2026	11-50	29 contacts →
	Exact match “Incorporated in 1971, Mechanical Sales, Inc.” Recorded in the RevenueBase company graph · Oct 14, 2026 · View company records in RevenueBase
9	Ecotope, INC	Exact match	Seattle, WA, United StatesHQ recorded Oct 14, 2026	11-50	28 contacts →
	Exact match “Ecotope has provided sustainable building design consulting and engineering services in the Pacific Northwest for over 40 years.” Recorded in the RevenueBase company graph · Oct 14, 2026 · View company records in RevenueBase
10	WJA Design Collaborative	Exact match	Seattle, WA, United StatesHQ recorded Oct 14, 2026	11-50	23 contacts →
	Exact match “WJA Design Collaborative, established in 1968 as Whiteley Jacobsen Associates, has provided architectural and engineering services to Federal clients and private contractors…” Recorded in the RevenueBase company graph · Oct 14, 2026 · View company records in RevenueBase
11	The Greenbusch Group	Exact match	Seattle, WA, United StatesHQ recorded Oct 14, 2026	11-50	21 contacts →
	Exact match “A multi-disciplinary engineering design firm, The Greenbusch Group is dedicated to exceptional design, successful partnerships, and sustainability in all our projects.” Recorded in the RevenueBase company graph · Oct 14, 2026 · View company records in RevenueBase
12	Pacific Engineering Technologies, INC	Exact match	Seattle, WA, United StatesHQ recorded Oct 14, 2026	11-50	15 contacts →
	Exact match Recorded description not available. Recorded in the RevenueBase company graph · Oct 14, 2026 · View company records in RevenueBase
13	GO Green Heating & AIR Conditioning	Exact match	Seattle, WA, United StatesHQ recorded Oct 14, 2026	1-10	8 contacts →
	Exact match “Where your family's comfort is our ideal." Go Green Heating & Air Conditioning is a Seattle -based HVAC company that has been established since 2015.” Recorded in the RevenueBase company graph · Oct 14, 2026 · View company records in RevenueBase
14	Integrity Energy Systems	Exact match	Seattle, WA, United StatesHQ recorded Oct 14, 2026	11-50	7 contacts →
	Exact match “Integrity Energy Systems is a HVAC company based out of Seattle, Washington, in the United States of America.” Recorded in the RevenueBase company graph · Oct 14, 2026 · View company records in RevenueBase
15	Sider Byers Mechanical Electrical Engineers	Exact match	Seattle, WA, United StatesHQ recorded Oct 14, 2026	11-50	5 contacts →
	Exact match “Sider + Byers is a mechanical and electrical engineering company based out of Seattle, WA.” Recorded in the RevenueBase company graph · Oct 14, 2026 · View company records in RevenueBase
16	CES Consulting LLC	Exact match	Seattle, WA, United StatesHQ recorded Oct 14, 2026	1-10	4 contacts →
	Exact match “We are a team of experienced electrical engineers and consultants, who provide strategic planning and advocacy for our clients around the globe.” Recorded in the RevenueBase company graph · Oct 14, 2026 · View company records in RevenueBase
17	Mechanical Energy Solutions LLC	Exact match	Seattle, WA, United StatesHQ recorded Oct 14, 2026	1-10	2 contacts →
	Exact match “At Mechanical Energy Solutions, we specialize in designing and building energy-efficient HVAC systems that make a difference.” Recorded in the RevenueBase company graph · Oct 14, 2026 · View company records in RevenueBase
18	FAC Systems INC	Exact match	Seattle, WA, United StatesHQ recorded Oct 14, 2026	1-10	1 contacts →
	Exact match Recorded description not available. Recorded in the RevenueBase company graph · Oct 14, 2026 · View company records in RevenueBase

RevenueBase SmartSearch

Describe a niche business in your own words. RevenueBase SmartSearch compares the meaning of your description with company business descriptions compiled in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit.

This list uses Exact for “hvac design engineering firms”. Each Exact match badge shows membership in that saved search; it is not an individual similarity score or a service-quality rating. Recorded descriptions are shown where available.

Showing 18 of 29 hvac design engineering firms based in Seattle, United States

See the full list, filter by size, metro and specialty, and access 542 tracked professional contacts with verified work emails. Direct dials are available where recorded.

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Hvac design engineering firms based in Seattle, United States at a glance

As of Oct 14, 2026

65.9%Verified-email coverage

28.4Average contacts per company

11-50Median size (employees)

Oct 14, 2026Page data refreshed

Companies by employee count

1-10

11-50

51-200

201-500

Email recency for this list is measured across the whole United States list rather than for Seattle, so it is reported there. Company counts and contact totals on this page are exact for Seattle, over 29 companies.

How this list was built

The recorded descriptions help you assess these company matches. Check a company’s website for its current services and locations.

Source: The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase SmartSearch, the natural-language company search available to every RevenueBase user.
What qualifies: Company records associated with Seattle, United States whose business descriptions match “hvac design engineering firms” by meaning at the Exact setting. Descriptions are compiled in the RevenueBase company graph from public websites, profiles and company information where available; they are not guaranteed quotations from the company's website.
RevenueBase SmartSearch: Describe a niche company in your own words to find businesses by meaning. Exact, Similar, Related and Broad control the breadth of RevenueBase SmartSearch. This saved list uses Exact. Each row's Exact match badge shows inclusion in that search, not an individual score or a service-quality judgment.
Public preview: The public preview omits records without a verified work email. Where headquarters information is recorded, preview rows are also filtered to this page’s location. Dataset totals and geographic summaries describe the full matched records before these preview filters.
Match quality: RevenueBase's August 25, 2026 study assessed 4,198 description/company pairs across matching settings. The publisher reports 86% good or better at Exact. This evaluates the method across queries; it does not audit this individual list. Recorded company descriptions, where available, help you judge each match yourself. Read the full methodology: how the lists are built and what the study measures.
Ranking: Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
Verification: Every displayed company carries at least one verified work email. RevenueBase tracks 542 professional contacts with verified work emails across the full matched dataset. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
Refresh: This page's figures were pulled from the company graph on October 14, 2026. Lists refresh periodically as the graph is re-checked.
Record context: Company records and descriptions can change. Check the company's website for its current services and locations.

Hvac design engineering firms by metro in the United States

Frequently asked

What is RevenueBase SmartSearch?

RevenueBase SmartSearch finds niche companies by the meaning of their business descriptions in the RevenueBase company graph. Exact, Similar, Related and Broad control how closely companies must fit your description. This list uses Exact for “hvac design engineering firms”; each Exact match badge shows search membership, not an individual similarity or quality score.

How many hvac design engineering firms are there based in Seattle, United States?

RevenueBase identified 29 company matches for hvac design engineering firms associated with Seattle, United States as of October 2026, using the meaning of business descriptions at Exact. This is the recorded matched set in the RevenueBase company graph.

What is the largest company on this list?

Hargis Engineers tops the displayed preview by professional contacts tracked in RevenueBase. Recorded headquarters appear in the company rows.

Which city in the United States has the most hvac design engineering firms?

New York leads the United States with 182 company records, followed by Houston (152) and Miami (74). Seattle has 29.

How do I get contact information for these companies?

A free RevenueBase account lets you run this exact search and work limited free results with 500 credits to start. Upgrading provides access to the 542 professional contacts with verified work emails tracked across these 29 companies; direct dials are available where recorded.

How current is this list?

The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on October 14, 2026.

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About this data

RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase SmartSearch, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.