How old are homes in Mukilteo, and what does that mean for a deck?
24% of homes in Mukilteo's covered ZIP code were built in 2000 or later and 4% before 1960; the largest group dates to the 1990s.
Homes in Mukilteo have a median construction year of 1989, so a deck original to a typical house would now be about 37 years old — beyond the point where wood framing, fasteners and flashing can be assumed sound.
Many decks from the 1970s and 1980s were built before today's detailed deck provisions appeared in model codes. Common issues on decks of this age include corroded hangers, posts set directly in soil and ledger boards fastened with nails. Replacement is often the better value than repeated repairs.
That is about the same as Snohomish County overall (median 1990). Statewide, the median Washington home was built in 1985. Among the 34 covered Washington communities with Census data, Mukilteo ranks #20 for oldest housing. In this ZIP code, 4% of homes were built before 1960, 23% between 1960 and 1979, 49% between 1980 and 1999, and 24% since 2000 — the single largest group dates to the 1990s.
| Decade built | Homes | Share |
|---|---|---|
| 2020 or later | 25 | 0% |
| 2010s | 404 | 5% |
| 2000s | 1,653 | 19% |
| 1990s | 2,171 | 25% |
| 1980s | 2,158 | 25% |
| 1970s | 1,528 | 17% |
| 1960s | 454 | 5% |
| 1950s | 158 | 2% |
| 1940s | 78 | 1% |
| before 1940 | 123 | 1% |
What does Mukilteo's climate mean for deck construction?
Mukilteo averages about 29 days a year at or below freezing, 3 inches of snow and 33.4 inches of precipitation, based on NOAA 1991–2020 normals.
The nearest NOAA climate station with 1991–2020 normals is Everett Snohomish AP. It records an average of 29 days a year with a low at or below 32°F — relatively few freezing nights. On roughly 27 of those days the temperature climbs back above freezing, so water in wood, soil and gaps between boards repeatedly freezes and thaws.
Frost is less severe in Mukilteo than in northern states, but footings still have to meet the local frost-depth requirement, and freeze-thaw cycles are enough to work loose nails and open checks in unsealed wood.
Snowfall is light — about 3 inches in an average year at Monroe — so occasional ice is a bigger concern than snow load. Textured boards and good drainage on stairs help on icy mornings.
Mukilteo sees about 33.4 inches of precipitation a year, with measurable rain or snow (0.1 inch or more) on about 92 days. Good drainage between boards, clean gaps and a ledger that is properly flashed keep that water from rotting the frame.
Summer heat is mild by comparison — average summer highs near 71°F and only about 1 days a year at 90°F or above — so board color can be chosen mostly on looks.
Which decking material makes the most sense in Mukilteo?
For most Mukilteo homes, composite or well-maintained wood is the strongest starting point.
Budget, upkeep tolerance and sun exposure on your particular lot still decide the final choice between these options.
| Material | How it handles Mukilteo's conditions |
|---|---|
| Pressure-treated pine | Economical; needs regular cleaning and sealing |
| Cedar | Attractive and stable; refinish to keep its color |
| Capped composite | Low maintenance; handles moisture and freeze-thaw well |
| PVC | Lightest and most moisture-proof; premium price |
What kinds of homes are in Mukilteo, and how does that shape deck design?
Mukilteo has about 8,752 housing units across its covered ZIP code. 60% are single-family detached homes, 4% are attached homes such as townhouses and rowhouses, and about 36% are in buildings with two or more units. Roughly 71% of occupied homes are owner-occupied.
The mix of detached homes and attached or multi-unit housing in Mukilteo means deck projects range from large backyard decks to compact rear decks on narrow lots. Lot size, neighbors' sightlines and any association rules shape the right design.
What deck projects are most common in Mukilteo?
Based on the age of Mukilteo's housing, the largest group of projects is likely to be replacing or rebuilding aging decks.
- Replacement and major repair: about 5,857 homes (67%) were built between 1970 and 1999, the age group whose original or early add-on decks are most likely to have worn-out framing, connectors and boards.
- Retrofit decks on older homes: about 813 homes (9%) predate 1970. Here the priority is confirming that add-on decks are properly attached — or rebuilding them freestanding — before any cosmetic work.
- Upgrades and expansions: about 429 homes (5%) were built since 2010. Their decks are usually sound but small or builder-grade, so enlarging the deck, adding stairs and switching to composite or upgraded railings are common.
When is the best time to plan a deck project in Mukilteo?
Mukilteo's milder winters — about 29 freezing nights a year — allow construction through most of the year. Spring and fall are still the busiest seasons, so booking early helps.
Do you need a permit to build a deck in Mukilteo?
Often, yes — especially for attached or elevated decks — but the rules are set locally. Check with the building department that serves your address: the municipality, or Snohomish County for unincorporated areas.
For Mukilteo, WA, ask the permit office whether your deck needs a permit based on its size, height and attachment to the house, which drawings and inspections are required. Statewide code background for Washington is on our state page; local rules change, so the building department remains the authority.
How does Mukilteo compare with nearby covered areas?
The closest covered area is Everett, about 4.6 miles from the center of Mukilteo's covered ZIPs. Its median home was built in 1985, 4 years earlier than in Mukilteo. Mukilteo has 11 percentage points more detached single-family homes (60% vs. 49%), which changes how many projects are backyard decks versus compact townhouse decks. Owner-occupancy is 71% in Mukilteo compared with 54% in Everett. Mukilteo's covered ZIP code span about 7.3 square miles of land with roughly 8,752 homes — about 1,199 per square mile, a typical suburban density where most homes have usable backyards.
| Area | Distance | Median year built | Covered ZIPs |
|---|---|---|---|
| Everett | 4.6 mi | 1985 | 4 |
| Lynnwood | 5.4 mi | 1991 | 3 |
| Edmonds | 6.3 mi | 1975 | 2 |
| Mountlake Terrace | 8 mi | 1973 | 1 |
| Bothell | 8.6 mi | 1997 | 3 |
| Kenmore | 11.5 mi | 1985 | 1 |
Deck planning checklist for Mukilteo homeowners
- Confirm your ZIP code is 98275, the covered Mukilteo ZIP.
- Find out when your current deck was built and whether it uses pre-2004 treated lumber.
- Probe the ledger, post bases and joist tops for soft wood before planning a resurface.
- Call 811 before any digging so utility lines are marked.

