# Mini Split Installation in Cedar Mill, OR

> Mini split installation in Cedar Mill: cooling for gas-heated houses with no central air, outdoor units sited under tall firs, and Washington County permits.

URL: https://firlandsportlandminisplits.com/service-areas/cedar-mill/

Service area, Oregon

Mini split installation in Cedar Mill: cooling for gas-heated houses with no central air, outdoor units sited under tall firs, and Washington County permits.

(971) 458-4515

Last Updated: November 12, 2026

70.2%

of Cedar Mill homes heat with natural gas (U.S. Census Bureau, ACS 5-year)

77.1%

of Cedar Mill homes are owner-occupied (ACS 5-year)

Permits

Washington County Building Services

Electric utility

PGE

## Rooms that need help in Cedar Mill

### Gas heat, no air conditioning

Seven in ten Cedar Mill homes heat with gas. An older one may never have had any cooling.

### Tall firs over the yard

Where a lot is shaded by Douglas firs, needles and cones decide where an outdoor unit can sit.

### A daylight basement below

Houses on sloping lots often have a basement that opens to the yard, which gives line sets a hidden route.

## Cooling a house that was built without it

Most Cedar Mill houses heat with gas and do it well. The trouble is July, when the house has no cooling and the window unit comes out of the garage again.

[Firlands Portland Mini Splits](https://firlandsportlandminisplits.com/) adds cooling to those houses without touching a furnace that still works. Cedar Mill has the highest share of gas heat among the west-side communities we serve: about seven in ten homes. That makes the job here mostly about cooling.

### Why not just add central air?

Central air needs ducts sized for cooling. In an older house the ducts were sized for heat, the upstairs runs are long, and adding an air conditioner to them leaves the hottest rooms behind. A head goes straight to the room that needs it.

Project

## A typical Cedar Mill daylight-basement cooling job

### The problem

The main-floor living and dining room faces west through a wall of windows and hits 85°F by evening in July. The gas furnace heats the house well, and there's no central air, just a window unit hauled out every summer.

### The house

The main floor sits a full story above the back yard, and the lot is shaded by tall Douglas firs. The furnace and panel are in the daylight basement, which opens to the yard through a sliding door.

### What we decide, and why

One 15,000 BTU head on the interior end wall of the open living and dining room cools the whole space; the furnace stays as the heat. We place the outdoor unit on a stand at the side of the house, ten feet from the nearest fir, where needles and cones don't drop straight onto the top of the unit.

### The work

The head's line set runs through the floor framing into the basement ceiling, along a joist bay and out the basement wall to the stand, about 30 feet in all, so nothing runs up the outside of the house. The 20-amp circuit comes from the panel a few feet away. Nitrogen test, vacuum below 500 microns, and the drain falls through the same route to daylight at the basement wall.

Running the lines through the basement ceiling hides them completely; a two-story outside cover on the back wall stays in plain view.

### What it changes

The living and dining room cools on summer evenings without a window unit, and the gas furnace keeps doing the heating.

Location

Cedar Mill, near Cornell Road

House

1968 daylight-basement house, about 2,100 square feet, gas furnace

Equipment

One 15,000 BTU cold-climate wall head, ground stand

Price

$6,950, permits included

Time on site

1 day, then the final inspections

## Under the firs: where the outdoor unit goes

On a wooded lot, the outdoor unit needs to sit out from under the canopy, with room to clean around it.

Where a lot has tall Douglas firs or big-leaf maples, they shade the house, which helps in summer. They also drop needles, cones and leaves all year.

- **Out from under the canopy.** We look for a spot where nothing drops straight onto the top of the unit, even if it adds a few feet of line set.
- **Up on a stand.** It keeps needles and leaves from piling against the coil.
- **Room to reach it.** At least a couple of feet on the service side for cleaning and repairs.
- **Away from the gutter line.** Overflowing gutters full of needles pour onto whatever sits below them.

Units under trees need a yearly cleaning more than most. [Mini split cleaning and maintenance](https://firlandsportlandminisplits.com/mini-split-cleaning-maintenance/) covers what that involves, and [mini split placement](https://firlandsportlandminisplits.com/guide/mini-split-placement/) covers clearances.

## Daylight basements and hidden line sets

Where a Cedar Mill house sits on a slope with a daylight basement, the basement ceiling is often the best route for a line set.

### Through the basement ceiling

A head on the main floor can run its line set down through the floor framing and along the basement ceiling to an outside wall at yard level. Nothing climbs the outside of the house, and the outdoor unit sits on level ground by the basement door.

### Heating the basement itself

A daylight basement used as a family room or office is often the coldest room in the house. A [basement mini split](https://firlandsportlandminisplits.com/basement-mini-split-installation/) heats and cools it on its own, and drains to daylight through the same wall.

## Permits: the county, not a city

Cedar Mill is unincorporated Washington County, so the county issues and inspects mini split permits here.

A Cedar Mill home may have a Portland mailing address, but that doesn’t make it a City of Portland permit.

### The Multnomah County edge

The census area also reaches east into Multnomah County, where Cedar Mill Creek begins, and there the permit office is different. We check the jurisdiction for your address on the first call, apply for both permits, book the inspections, and close the job out with the final. [Mini split permits](https://firlandsportlandminisplits.com/guide/mini-split-permit-portland/) explains the inspections.

## Spring and fall without the furnace

A head that cools in July also heats, and in a gas-heated house that’s useful in the shoulder seasons.

On a 45°F October morning, firing the furnace to warm the whole house for the one room you’re sitting in wastes gas. A head warms that room alone, efficiently, and the furnace waits for real winter. We pick cold-climate models even for cooling-first jobs, so the head can carry its room well into winter if you want it to.

## Cooling more than one room

When the bedrooms upstairs and the main-floor living space all run hot, a multi-zone system covers them from one outdoor unit.

- **Two heads.** The living room and the primary bedroom, where most of the day and night are spent.
- **Three or four heads.** Every bedroom plus the living space, on one outdoor unit sized for all of them. [Multi-zone mini split installation](https://firlandsportlandminisplits.com/multi-zone-mini-split-installation/) covers the details.
- **Sized together.** We size the outdoor unit to what the rooms need at the same moment, not the sum of every head running flat out.

## What a Cedar Mill install costs

Firlands’ typical range for one head is $4,000 to $8,500, and two heads on one outdoor unit run $6,500 to $12,000.

Three or four heads run $9,000 to $18,000 and up, for a house where several rooms need cooling. Washington County permit fees are in the price. [Mini split installation cost](https://firlandsportlandminisplits.com/guide/mini-split-installation-cost-portland/) shows what moves a job within the range.

### The incentive question

Cedar Mill is PGE territory, but Energy Trust of Oregon’s ductless incentive only applies when the new system replaces electric resistance heat in the main living space. In a gas-heated house adding cooling, it doesn’t. A house with baseboards in the living room can qualify for $800.

## Window unit, central air or a head?

For one or two rooms, a head beats a window unit on noise and comfort; for the whole house, it depends on the ducts.

| Option | Best for | The catch |
| --- | --- | --- |
| Window unit | One room, lowest up-front cost | Noisy, blocks a window, cooling only |
| Mini split head | One to four rooms, heat and cool | Higher up-front cost |
| Central air on the furnace | A house with ducts sized for cooling | Upstairs rooms often lag |

[Mini split vs window AC](https://firlandsportlandminisplits.com/guide/mini-split-vs-window-ac/) and [mini split vs central heat pump](https://firlandsportlandminisplits.com/guide/mini-split-vs-central-heat-pump/) go further. Closed windows also help on smoky days; [do mini splits filter wildfire smoke?](https://firlandsportlandminisplits.com/guide/do-mini-splits-filter-wildfire-smoke/) explains what a head’s filter can and can’t do.

## Along Cornell Road and beyond

Cedar Mill’s housing runs from the 1950s and 1960s through the 2000s, and the age of the house shapes the job.

- **Around Cornell and Saltzman.** Older houses, some on wooded lots or with daylight basements: cooling added to gas heat.
- **Toward Barnes Road and Leahy Road.** Where a street climbs the hill, the outdoor unit spot takes planning.
- **The newer subdivisions.** Houses with central air, where a [single-zone head](https://firlandsportlandminisplits.com/single-zone-mini-split-installation/) handles one hot room.

## Services in Cedar Mill

- [Service**Single-zone installation** Single zone mini split installation: one indoor head and one outdoor unit for the room the furnace never reaches, sized to that room.](https://firlandsportlandminisplits.com/single-zone-mini-split-installation/)
- [Service**Multi-zone installation** Multi zone mini split installation: two to five rooms on one outdoor unit, each head sized to its own room and set to its own temperature.](https://firlandsportlandminisplits.com/multi-zone-mini-split-installation/)
- [Service**Basement** A basement mini split install for a family room, office or basement unit: heat, cooling, drier air and a drain that works below grade.](https://firlandsportlandminisplits.com/basement-mini-split-installation/)
- [Service**Cleaning and maintenance** Mini split cleaning in Portland: deep cleans for musty or weak heads, and a yearly visit that keeps filters, coils and drains clear.](https://firlandsportlandminisplits.com/mini-split-cleaning-maintenance/)
- [Service**Whole-house systems** Whole house mini split installation: every room heated and cooled by ductless heads, planned as one system with a winter backup plan.](https://firlandsportlandminisplits.com/whole-house-mini-split/)

## How a job usually runs in Cedar Mill

### The call

You tell us the rooms and send a few photos; we give a rough range.

### The visit

We measure each room, look at the walls, the panel and where the outdoor unit can go.

### The estimate

A written estimate: each head, the line-set route, drains, circuit, permits and price.

### Install and handover

Pressure test, vacuum, startup, a walk-through, and the permits closed out.

## Neighborhoods, landmarks and routes

- Cedar Mill town center
- Cornell Road corridor
- Saltzman Road area
- Barnes Road area
- Leahy Road area
- Murray Road area
- Sunset High School area

### Landmarks

- Cedar Mill Community Library
- Cedar Mill Falls
- John Quincy Adams Young House
- Cedar Mill Creek
- Sunset Swim Center

### Getting around

- Cornell Road east-west
- Highway 26 (Sunset Highway) along the south edge
- Saltzman Road
- Barnes Road
- Murray Boulevard

[Open Cedar Mill, Oregon in Google Maps](https://www.google.com/maps/search/?api=1&query=Cedar%20Mill%2C%20Oregon)

## Cedar Mill: questions

### How much does it cost to add a mini split in Cedar Mill?

Firlands' typical range for one head is $4,000 to $8,500, and two heads on one outdoor unit $6,500 to $12,000. Washington County permit fees are included. The visit and the written estimate set your price.

### Who issues mini split permits in Cedar Mill?

Washington County Building Services, because Cedar Mill is unincorporated. A few homes at the east edge of the area sit across the line in Multnomah County, with a different permit office. We confirm the jurisdiction for your address before we quote.

### Will fir needles clog a mini split outdoor unit in Cedar Mill?

They can block the coil if the unit sits right under a tree. We place it out from under the canopy where we can, and a yearly cleaning clears the coil and the base pan. Needles left in the base pan also hold water against it.

### Can I add a mini split and keep my gas furnace in Cedar Mill?

Yes. A head takes over the cooling in the rooms that need it and can heat them in spring and fall, while the furnace stays as the main heat. Energy Trust's ductless incentive doesn't apply to a gas-heated main living space.

### Does a mini split help with wildfire smoke in Cedar Mill?

It lets you keep the windows shut on smoky summer days and stay cool. A head's filter catches some particles, but it isn't a substitute for a dedicated air cleaner with a high-efficiency filter.

## Nearby service areas

- [Oregon**Oak Hills** Mini split installation in Oak Hills: cooling post-and-beam houses with radiant floors and no attic, lines kept off exposed beams, Washington County permits.](https://firlandsportlandminisplits.com/service-areas/oak-hills/)
- [Oregon**Bethany** Mini split installation in Bethany: third-floor bonus rooms and offices the central air can't cool, an honest duct check first, and Washington County permits.](https://firlandsportlandminisplits.com/service-areas/bethany/)
- [Oregon**Beaverton** Mini split installation in Beaverton: wall heaters and baseboards replaced room by room, townhouse layouts, City of Beaverton permits and typical ranges.](https://firlandsportlandminisplits.com/service-areas/beaverton/)

## Guides for houses in Cedar Mill

- [Decision Guide**Window AC vs mini split: which is right for your room?** A summer stopgap or a permanent system that also heats. What each one does to the room, the bill and the window.](https://firlandsportlandminisplits.com/guide/mini-split-vs-window-ac/)
- [Decision Guide**Mini split vs central heat pump: which fits a Portland house?** It comes down to your ducts: whether they exist, where they reach, and what shape they're in.](https://firlandsportlandminisplits.com/guide/mini-split-vs-central-heat-pump/)
- [Learn**Do mini splits filter wildfire smoke?** What a ductless head does with smoky air, what it can't catch, and how to keep one room clean in a Portland smoke week.](https://firlandsportlandminisplits.com/guide/do-mini-splits-filter-wildfire-smoke/)
- [Learn**Where should a mini split go?** Head placement inside, the outdoor unit outside, and the Portland rules and weather that decide both.](https://firlandsportlandminisplits.com/guide/mini-split-placement/)

## Get an estimate in Cedar Mill

Tell us which rooms aren't working and where the house is in Cedar Mill.

(971) 458-4515