Research by DoINeedAPermit Research Team · Updated May 2026
The Short Answer
Most heat pump installations in Longview require a permit from the City of Longview Building Department, except for like-for-like replacements of existing units pulled by a licensed contractor. New installs, conversions from gas furnaces, and supplemental heat-pump additions always need a permit.
Longview's building code adoption lags the state by one code cycle—the city currently enforces the 2015 International Energy Conservation Code (IECC) rather than the 2021 version. This means your heat pump must meet the 2015 IECC efficiency baseline, which is less stringent than what King County or Seattle demands, but still requires a Manual J load calculation signed by a licensed HVAC designer. The City of Longview Building Department does not maintain an online permit portal; all applications must be submitted in person at City Hall or via mail, which extends permitting timelines compared to Spokane or other Cowlitz County municipalities. Cowlitz County PUD offers substantial rebates ($500–$1,500 depending on efficiency rating) but only honors permits filed with the city before installation. Federal IRA tax credits (30%, up to $2,000 for qualified heat pumps) apply nationwide, but Longview's slower code cycle means fewer ENERGY STAR Most Efficient units are automatically pre-qualified locally—you'll need to verify nameplate efficiency with the contractor and the permit reviewer.

What happens if you skip the permit (and you needed one)

Longview heat pump permits—the key details

Longview Building Department enforces the 2015 International Energy Conservation Code (IECC) and the 2015 International Residential Code (IRC), which means your heat pump must meet minimum seasonal energy efficiency ratios (SEER 13–14 depending on split vs. packaged configuration). Unlike Seattle or Portland, Longview does not impose additional local electrification mandates or stretch-code requirements, so there is no pressure to downsize your backup resistive heater or upgrade to a cold-climate-rated unit. However, Manual J load calculations are mandatory—you must provide a signed calculation of your home's heating and cooling load (based on square footage, insulation R-value, window orientation, and local design temps). Longview's winter design temp is 6°F; summer is 78°F; the load calc must account for both. If the existing ductwork is undersized or damaged, the permit reviewer will require ductwork upgrades before final approval. This is the most common rejection reason: a contractor tries to fit a 3-ton heat pump into a home with 2-ton ductwork, and the system cannot deliver air. Plan for $300–$800 in ductwork evaluation costs if your home was built before 2000.

Electrical code for heat pumps in Longview falls under NEC Article 440 (motor-driven appliances) and IRC Chapter 24 (electrical). The outdoor condensing unit (compressor) draws 20–40 amps depending on tonnage; the indoor air handler (if separate from the coil) draws 5–15 amps; any resistive backup heater or emergency heat strips draw an additional 20–40 amps. Your service panel must have available amperage—many older Longview homes have 100-amp panels that cannot accommodate a heat pump without upgrade. A 100-amp panel upgrade costs $1,500–$3,000 and requires a separate electrical permit. The permit reviewer will ask for a line-load calculation from your contractor showing all connected loads (HVAC, water heater, electric range, etc.) and available breaker space. Unlike some jurisdictions, Longview does not require a dedicated 240V circuit for the compressor, but it is best practice and may be required by your installer. Refrigerant line set installation must follow manufacturer specifications for line length (typically 25–50 feet maximum) and must include an access valve for servicing. Condensate drainage from the indoor coil must be hard-piped to a floor drain, sump, or exterior splash block—no vinyl tubing left unsupported or left in crawlspaces where it can freeze or clog. The permit will include a rough mechanical inspection (before walls are closed) and a final electrical inspection (after wiring is complete).

Longview's 12-inch frost depth (Puget Sound side) and 30+ inches on the eastern slope create distinct mechanical requirements. If your heat pump outdoor unit is sited on grade in a low-lying area, condensate can pool and refreeze in winter, clogging the drain pan. The code requires proper site grading or a heated condensate pan (integral to many cold-climate-rated units). If the unit is mounted on a roof or elevated foundation, condensate lines must be insulated with 1/2-inch foam to prevent icing. Some contractors use heat-trace cable (electric-ribbon heating) around outdoor drain lines in Longview's climate, which adds $200–$400 and requires a separate 120V outlet near the unit. This is not always required by code but is a common best practice. Similarly, if your heat pump is being installed in an uninsulated garage, attic, or crawlspace, the building department may require the air handler to be in conditioned space or insulated with R-13 fiberglass. Backup heat (resistive strips or gas) is strongly recommended for homes in the 5B zone (east of the Cascades), where winter temps can drop to -10°F; systems without backup heat may be approved but will be noted on the permit as 'supplemental heat required'—meaning you'll still need a secondary heating source for extreme cold.

Longview Building Department does not maintain an online permit portal; all applications must be submitted in person at City Hall (501 Kelso Drive, Longview, WA 98632, or verify the current address) during business hours (Mon–Fri, 8 AM–5 PM; hours subject to change—call ahead). The application includes the homeowner's information, contractor's license number and insurance certificate, a completed HVAC permit form (available at the counter or via mail request), a one-line electrical diagram showing the heat pump connection to the service panel, a copy of the Manual J load calculation, and a site plan showing the outdoor unit location and condensate drainage routing. If you are the homeowner performing your own installation (owner-builder), you must have a Washington State Department of Labor journeyman HVAC card or a contractor's license; Longview does not allow owner-builders to install mechanical systems without licensing. Many homeowners mistakenly assume owner-builder exemptions apply to HVAC—they do not. Processing time is typically 5–7 business days for plan review (if no rejections); most heat pump permits are issued as 'over-the-counter' (OTC) approvals without a full engineering review, provided all documents are complete. Once approved, the permit is valid for 180 days; if work is not started within that window, renewal is required.

Federal IRA tax credits (30% of equipment cost, up to $2,000) and Cowlitz County PUD rebates ($500–$1,500 depending on SEER rating) are only available on city-permitted installations. The permit application must be filed BEFORE work begins; retroactive permits issued after installation will not qualify for rebates. To maximize rebates, your contractor should recommend an ENERGY STAR Most Efficient unit (typically SEER 16–20), which qualifies for both federal credits and top-tier PUD bonuses. Longview's 2015 IECC baseline is SEER 13–14, so any system above that threshold will earn rebates. Some heat pump brands (Lennox, Carrier, Daikin) have pre-approved rebate partners in Cowlitz County; ask your contractor for a rebate quote before signing the contract. The permit fee itself is $150–$300 for a straight heat pump replacement, and $300–$500 for a new install with ductwork upgrades. If an electrical panel upgrade is required, that is a separate $200–$400 permit. Total permitting cost: $350–$900. Timeline from permit application to final inspection is typically 3–4 weeks if no rejections; with rejections (missing load calc, undersized panel, condensate routing not shown), add 2–3 weeks.

Three Longview heat pump installation scenarios

Scenario A
Like-for-like heat pump replacement, 3-ton split system, same outdoor location, licensed contractor
Your 2008 Lennox 3-ton heat pump failed during winter; you call a licensed HVAC contractor to install an identical Lennox 3-ton replacement in the same outdoor pad location. The contractor has a current Washington State HVAC license and $1 million liability insurance. Longview Building Department permits this as a 'direct replacement' with no permit required if the contractor files a one-page 'Equipment Replacement Notice' (some jurisdictions exempt this entirely; Longview currently requires the notice to be on file for warranty documentation). The contractor charges $6,500 for labor and equipment; no permit fees apply. Inspections are not required. However, if you or the homeowner chooses to file a full permit anyway (to document the work for resale or insurance), Longview will issue one over-the-counter for $150–$200. This is optional but recommended if the home will be sold within 5 years. The replacement takes 1–2 days. Cowlitz County PUD will not rebate this replacement unless a permit is filed; if you file the permit and the new unit is ENERGY STAR rated, you may qualify for a $500–$800 rebate. Total cost without permit: $6,500. Total cost with optional permit and rebate: $6,500 + $150 permit – $650 rebate = $6,000. Decision: file the permit if resale is planned; skip it if the unit will run for 10+ years before sale.
Like-for-like replacement | Optional permit $150–$200 | Rebate up to $800 if permit filed | No inspections required | Licensed contractor required | 1–2 day install
Scenario B
Gas furnace to heat pump conversion, 4-ton system, existing ductwork, new electrical panel required, east Longview (5B zone)
You own a 1970s ranch home in east Longview with an aging propane furnace; you want to convert to a 4-ton cold-climate heat pump with backup resistive heat strips. Your existing 100-amp service panel has no breaker space for the 35-amp compressor circuit plus the 40-amp backup heat circuit. The contractor submits a full permit application including a Manual J load calculation (home is 1,600 sq ft, R-11 walls, single-pane windows, poor insulation). The calculation shows a 4-ton unit is required to maintain 68°F on a -10°F design day (east-side extreme cold). Longview Building Department issues a conditional approval: (1) electrical permit required for 200-amp panel upgrade ($1,800 material and labor, $350 electrical permit), (2) rough mechanical inspection after refrigerant lines are installed and pressure-tested, (3) final electrical inspection after all wiring is complete and the compressor is hard-wired to a dedicated 240V circuit. The backup heat strips are mounted in the indoor air handler; the permit reviewer requires insulation of the air handler if installed in the attic (R-13 minimum). The outdoor unit is on grade in the backyard; the permit specifies a heated condensate pan (extra $150) to prevent freeze-up in the 5B zone. Total permit fee: $450 (HVAC) + $350 (electrical) = $800. Contractor labor and equipment: $12,000. Electrical panel: $1,800. Condensate pan: $150. Total cost: $14,750. Timeline: 2 weeks for permit review, 3 days for installation, 1 week for inspections = 3.5 weeks start to finish. Cowlitz County PUD rebate: $1,200 (cold-climate unit, SEER 17). Federal IRA credit: $2,000 (30% of $6,700 equipment, capped at $2,000). Net cost: $14,750 – $1,200 – $2,000 = $11,550 out-of-pocket.
Permit required | HVAC permit $450 | Electrical permit $350 | Panel upgrade $1,800 | Heated condensate pan $150 | Cold-climate unit (backup heat) | Manual J load calc required | Rough mechanical + final electrical inspections | 3.5 weeks timeline | $1,200 PUD rebate + $2,000 federal credit
Scenario C
Supplemental heat pump addition to existing forced-air furnace, 2-ton ductless mini-split, owner-builder attempt
You want to install a ductless 2-ton mini-split heat pump in your master bedroom and kitchen to reduce reliance on your gas furnace during mild seasons. You purchase a Fujitsu unit online for $3,200 and attempt a DIY installation using YouTube videos and a rented vacuum pump. You do not hold a Washington State HVAC license. When you submit the permit application, Longview Building Department rejects it immediately: owner-builders cannot perform mechanical HVAC work in Washington State without a current journeyman HVAC card or a state-licensed contractor's license. This is non-negotiable. You must hire a licensed contractor to complete the installation. The contractor charges $2,500 for labor (refrigerant line set installation, electrical wiring, vacuum-and-charge procedure, condensate drainage). A permit is filed ($250 for supplemental system). The system requires two separate 240V circuits (one per indoor head unit), which may require a sub-panel or upgrade to the existing panel if breaker space is unavailable. Assuming breaker space is available, no electrical permit is needed; the HVAC contractor's electrician runs the wire. The installation takes 2 days. Rough mechanical inspection occurs after refrigerant lines are pressure-tested and before drywall is closed. Final inspection is after all electrical is complete. Cowlitz County PUD will rebate $400–$600 (2-ton supplemental system, SEER 16). Federal IRA credit does not apply to supplemental units, only primary systems. Total cost: $3,200 (equipment) + $2,500 (labor) + $250 (permit) = $5,950. Net after rebate: $5,950 – $500 = $5,450. If you had installed it yourself without a permit, City of Longview would issue a stop-work order (cost: $2,000–$3,000 additional for removal and proper reinstallation) and you would forfeit the rebate entirely. Lesson: ductless mini-splits are a popular supplemental strategy in Longview, but they still require a licensed contractor and a city permit.
Supplemental system | Permit required $250 | Licensed contractor mandatory | Owner-builder NOT allowed for HVAC | 2-ton ductless mini-split | $400–$600 PUD rebate | No federal IRA credit for supplemental units | 2-day install + inspections | 2–3 week permitting timeline

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Longview's 2015 IECC and why your heat pump efficiency baseline is lower than King County or Seattle

Longview adopted the 2015 International Energy Conservation Code as its energy standard, while King County and Seattle use the 2021 IECC (or stretch-code amendments). This one-cycle lag means Longview does not mandate heat pump systems meet the HSPF2 (Heating Seasonal Performance Factor 2) standard that newer codes enforce. SEER and SEER2 ratings differ: SEER is the older cooling-season metric; SEER2 accounts for part-load efficiency (how the system runs 90% of the time). A unit rated SEER 14 (2015 baseline) might be SEER2 11 in the newer metric—still efficient but not as impressive on paper. For permitting purposes, Longview Building Department accepts any unit meeting SEER 13 minimum (2015 IECC baseline for split systems). This means you can legally install a lower-cost Goodman or AirEase unit at SEER 13–14 and pass inspection, whereas Seattle would require SEER 16+ to qualify for local rebates.

Cowlitz County PUD's rebate structure recognizes the gap. The county offers $500–$600 rebates for SEER 13–15 units (Longview baseline), but top-tier rebates of $1,200–$1,500 for SEER 16+ or cold-climate-rated units. Federal IRA credits (30%, up to $2,000) do not distinguish by SEER rating; they apply to any ENERGY STAR-certified heat pump. So a homeowner who chooses a higher-efficiency unit (SEER 17, HSPF2 9+) will spend $500–$1,500 more upfront but recover $1,200 in utility rebates plus $2,000 federal credit, effectively netting $2,700–$4,000 in incentives. Longview's building department does not pre-approve manufacturer lists; you must confirm ENERGY STAR certification with your contractor before filing the permit application.

The 2015 IECC also does not require Manual J load calculations in all cases—only for 'new installations' and 'replacements in jurisdictions with recent code adoption.' Longview's older standard sometimes allows HVAC designers to use rule-of-thumb sizing (square footage × tonnage-per-ton table). However, best practice (and most contractors' insurance requirements) demand a signed Manual J regardless. If the permit reviewer flags an undersized or oversized system, you will be required to submit the calculation before approval. Plan for $200–$400 in engineering costs for a licensed HVAC designer to perform a Manual J; it typically takes 1–2 business days.

Cowlitz County PUD rebates and why permits unlock money you can't claim otherwise

Cowlitz County Public Utility District (PUD) is the local electric utility serving Longview. The PUD offers heat pump rebates as part of its regional energy conservation program, funded by ratepayer surcharges and state incentives. Rebate amounts depend on system type, efficiency rating, and whether the home is all-electric or has backup gas heat. A 3-ton SEER 14 split system replacing an electric furnace qualifies for $500–$600. A cold-climate unit (SEER 16–18, HSPF2 8.5+) replacing gas qualifies for $1,200–$1,500. Ductless mini-splits (supplemental) qualify for $200–$400. The single non-negotiable requirement: the permit must be filed with the City of Longview Building Department before the contractor breaks ground. Retroactive permits issued after equipment is installed do not qualify for rebates. The PUD inspects the final installation and verifies nameplate efficiency; they cross-reference the permit number with the city's records. If no permit exists, rebate is denied, no exceptions.

The rebate application process takes 4–6 weeks after final inspection. The contractor or homeowner submits a rebate claim form with the permit number, the AHRI (Air Conditioning, Heating, and Refrigeration Institute) certificate of the installed unit, and proof of purchase (invoice). The PUD mails a check 60–90 days later. This timing is important: many homeowners assume the rebate will offset the permit cost immediately. It does not. You must pay the full system cost upfront and wait 3–4 months for reimbursement. Some contractors offer 'rebate financing'—they absorb the cost and refund it to you once the PUD check arrives—but this is not standard. Plan your budget accordingly.

Federal IRA tax credits (30% of equipment and installation labor, up to $2,000) are separate from PUD rebates and stack together. A $7,000 heat pump system that earns a $1,200 PUD rebate and a $2,000 federal credit reduces your net cost to $3,800. These incentives are why filing the permit (cost: $150–$500) is almost always cost-effective. Skip the permit, and you forfeit $3,200–$4,700 in incentives. The math almost always favors permitting.

City of Longview Building Department
Longview City Hall, 501 Kelso Drive, Longview, WA 98632 (confirm address locally)
Phone: Call Longview City Hall main line; building department extension varies — verify online or call 360-442-5000
Monday–Friday, 8:00 AM – 5:00 PM (hours subject to change; verify before visiting)

Common questions

Do I need a permit to replace my heat pump with the exact same model and tonnage?

If a licensed HVAC contractor is performing the replacement, Longview allows a 'direct replacement' with only a one-page Equipment Replacement Notice filed at the city; a full permit is not required. However, filing an optional permit ($150–$200) is recommended if you plan to sell the home within 5 years, as it documents the work for title transfer. More importantly, filing the permit qualifies you for Cowlitz County PUD rebates ($500–$800 if the unit is ENERGY STAR rated), which you cannot claim without a permit. Owner-builders cannot perform even a like-for-like replacement without a licensed contractor.

What is a Manual J load calculation, and why is Longview Building Department requiring one?

A Manual J is an engineering calculation of your home's heating and cooling load (in BTU per hour) based on square footage, insulation R-value, window area, orientation, local design temperatures, and occupancy. Longview's winter design temperature is 6°F; summer is 78°F. The calculation determines the correct tonnage of the heat pump (3-ton, 4-ton, 5-ton, etc.). An undersized unit cannot maintain comfort; an oversized unit short-cycles (runs inefficiently). The Building Department requires a signed Manual J from a licensed HVAC designer to ensure the system is right-sized. Cost: $200–$400, typically completed in 1–2 business days.

Can I do a DIY heat pump installation if I have some HVAC experience?

No. Washington State law prohibits any person without a current journeyman HVAC license or state-licensed contractor license from installing, maintaining, or servicing mechanical HVAC systems, including heat pumps. 'Owner-builder' exemptions that apply to electrical work or some plumbing do not extend to HVAC. Violation results in stop-work orders ($2,000–$3,000 additional cost), loss of rebates, voided warranties, and potential liability for injury. You must hire a licensed contractor.

What happens if the permit reviewer rejects my application?

Common rejection reasons in Longview include: missing or incorrect Manual J load calculation, service panel lacking breaker space for the compressor circuit, condensate drainage not shown on the site plan, or ductwork undersized for the tonnage. The reviewer will send a written rejection notice listing specific deficiencies. You have 180 days to correct and resubmit; this adds 1–2 weeks to the timeline. Working with an experienced contractor before filing dramatically reduces rejection risk, as the contractor typically prepares the application package.

How much does a heat pump permit cost in Longview?

HVAC permits range from $150–$300 for like-for-like replacements and $300–$500 for new installs or system conversions. If an electrical panel upgrade is required, add $200–$400 for an electrical permit. Fees are based on project scope and estimated system cost. There is no online fee calculator; the Building Department quotes the fee during the in-person application or via phone request.

Can I claim both a PUD rebate and a federal IRA tax credit on the same heat pump?

Yes, they stack. The Cowlitz County PUD rebate (typically $500–$1,500) and the federal IRA tax credit (30% of equipment cost, up to $2,000) are separate incentive programs and do not reduce each other. A $7,000 system earning both credits nets approximately $3,800–$4,200 out-of-pocket. Both programs require a city permit filed before installation.

What inspections are required for a heat pump installation in Longview?

Typically two inspections: (1) rough mechanical after refrigerant lines are installed and pressure-tested, and before drywall is closed; (2) final inspection after all electrical wiring is complete and the compressor is operational. If a new electrical panel is required, a third inspection by the electrical inspector is needed. The contractor schedules inspections via the Longview Building Department. Most inspections occur within 2–3 business days of request.

My home is in east Longview (5B climate zone). Are there special requirements for cold-climate heat pumps?

Yes. Longview's east side (5B zone, winter lows to -10°F) requires or strongly encourages cold-climate-rated heat pumps with backup resistive heat or gas heating. The permit reviewer will note whether backup heat is included. Cold-climate units (HSPF2 8.5+, SEER 16+) are more expensive ($500–$1,500 premium) but essential for reliable winter performance and qualify for higher PUD rebates ($1,200–$1,500 vs. $500–$600 for standard units). Additionally, outdoor condensate drain lines must be insulated or equipped with a heated pan to prevent freeze-up. This is often included in cold-climate unit packages but should be confirmed with your contractor.

How long does it take to get a heat pump permit approved in Longview?

Plan review typically takes 5–7 business days if the application is complete and requires no rejections. Most heat pump permits are issued 'over-the-counter' (OTC) with no full engineering review, provided all documents are submitted correctly. Installation can begin immediately after permit issuance. Total timeline from application to final inspection is 3–4 weeks. If rejections occur (missing load calc, panel upgrade required, etc.), add 2–3 weeks for resubmission and re-review.

What is the difference between a 'supplemental' heat pump and a 'primary' system for rebate purposes?

A primary system replaces or is the main heating source (e.g., gas furnace to heat pump conversion, or new construction). A supplemental system adds to an existing primary heating system (e.g., a ductless mini-split in one room alongside a running furnace). Supplemental systems qualify for smaller PUD rebates ($200–$400) and do not qualify for federal IRA tax credits (which apply only to primary systems). Both require permits. If you already have a functioning furnace and want to reduce gas usage during mild seasons, a supplemental mini-split is an affordable option; just expect lower incentive rewards than a full conversion.

Disclaimer: This guide is based on research conducted in May 2026 using publicly available sources. Always verify current heat pump installation permit requirements with the City of Longview Building Department before starting your project.