How old are homes in Kenmore, and what does that mean for a deck?
26% of homes in Kenmore's covered ZIP code were built in 2000 or later and 12% before 1960; the largest group dates to the 1980s.
Homes in Kenmore have a median construction year of 1985, so a deck original to a typical house would now be about 41 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 King County overall (median 1983). Statewide, the median Washington home was built in 1985. Among the 34 covered Washington communities with Census data, Kenmore ranks #13 for oldest housing. In this ZIP code, 12% of homes were built before 1960, 28% between 1960 and 1979, 34% between 1980 and 1999, and 26% since 2000 — the single largest group dates to the 1980s.
| Decade built | Homes | Share |
|---|---|---|
| 2020 or later | 151 | 2% |
| 2010s | 1,230 | 13% |
| 2000s | 1,161 | 12% |
| 1990s | 1,158 | 12% |
| 1980s | 2,194 | 22% |
| 1970s | 1,286 | 13% |
| 1960s | 1,455 | 15% |
| 1950s | 782 | 8% |
| 1940s | 172 | 2% |
| before 1940 | 172 | 2% |
What does Kenmore's climate mean for deck construction?
Kenmore averages about 25 days a year at or below freezing, 3.8 inches of snow and 37.8 inches of precipitation, based on NOAA 1991–2020 normals.
The nearest NOAA climate station with 1991–2020 normals is Seattle Sand Pt Wsfo, about 4 miles away. It records an average of 25 days a year with a low at or below 32°F — relatively few freezing nights. On roughly 24 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 Kenmore 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 3.8 inches in an average year at Seattle Sand Pt Wsfo — so occasional ice is a bigger concern than snow load. Textured boards and good drainage on stairs help on icy mornings.
Kenmore sees about 37.8 inches of precipitation a year, with measurable rain or snow (0.1 inch or more) on about 95 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 75°F and only about 2 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 Kenmore?
For most Kenmore 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 Kenmore'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 Kenmore, and how does that shape deck design?
Kenmore has about 9,761 housing units across its covered ZIP code. 63% are single-family detached homes, 4% are attached homes such as townhouses and rowhouses, and about 33% are in buildings with two or more units. Roughly 69% of occupied homes are owner-occupied.
The mix of detached homes and attached or multi-unit housing in Kenmore 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 Kenmore?
Based on the age of Kenmore's housing, the largest group of projects is likely to be replacing or rebuilding aging decks.
- Replacement and major repair: about 4,638 homes (48%) 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 2,581 homes (26%) 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 1,381 homes (14%) 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 Kenmore?
Kenmore's milder winters — about 25 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 Kenmore?
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 King County for unincorporated areas.
For Kenmore, 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 Kenmore compare with nearby covered areas?
The closest covered area is Mountlake Terrace, about 4 miles from the center of Kenmore's covered ZIPs. Its median home was built in 1973, 12 years earlier than in Kenmore. Kenmore has 12 percentage points more detached single-family homes (63% vs. 51%), which changes how many projects are backyard decks versus compact townhouse decks. Owner-occupancy is 69% in Kenmore compared with 57% in Mountlake Terrace. Kenmore's covered ZIP code span about 6.2 square miles of land with roughly 9,761 homes — about 1,574 per square mile, a typical suburban density where most homes have usable backyards.
| Area | Distance | Median year built | Covered ZIPs |
|---|---|---|---|
| Mountlake Terrace | 4 mi | 1973 | 1 |
| Kirkland | 4.1 mi | 1983 | 2 |
| Bothell | 4.7 mi | 1997 | 3 |
| Lynnwood | 6.1 mi | 1991 | 3 |
| Woodinville | 6.5 mi | 1987 | 2 |
| Edmonds | 7 mi | 1975 | 2 |
Deck planning checklist for Kenmore homeowners
- Confirm your ZIP code is 98028, the covered Kenmore 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.

