Deck builders in Bothell, WA

The median home in Bothell was built around 1997. A deck built with a house of that age is now about 29 years old — the stage where first-generation pressure-treated decks commonly need major repair or replacement.

Decks built before 2004 were very likely made with CCA-treated lumber, which was phased out of most residential uses at the end of 2003. That doesn't make an existing deck unsafe, but old boards shouldn't be burned, and demolition debris should be disposed of according to local rules.

That makes Bothell's housing 7 years newer than Snohomish County as a whole, where the median home was built in 1990. Statewide, the median Washington home was built in 1985. Among the 34 covered Washington communities with Census data, Bothell ranks #30 for oldest housing. In these ZIP codes, 3% of homes were built before 1960, 18% between 1960 and 1979, 33% between 1980 and 1999, and 46% since 2000 — the single largest group dates to the 2010s.

The nearest NOAA climate station with 1991–2020 normals is Seattle Sand Pt Wsfo, about 6 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 Bothell 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.

Bothell 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.

Because so many Bothell homes were built after 2000, matching the deck to vinyl or fiber-cement siding and existing trim colors is often part of the material decision.

Bothell has about 54,294 housing units across its covered ZIP codes. 61% are single-family detached homes, 6% are attached homes such as townhouses and rowhouses, and about 33% are in buildings with two or more units. Roughly 68% of occupied homes are owner-occupied.

The mix of detached homes and attached or multi-unit housing in Bothell 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.

• Replacement and major repair: about 24,979 homes (46%) 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.
• Upgrades and expansions: about 13,556 homes (25%) 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.
• Retrofit decks on older homes: about 4,353 homes (8%) predate 1970. Here the priority is confirming that add-on decks are properly attached — or rebuilding them freestanding — before any cosmetic work.

Bothell'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.

For Bothell, 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.

The closest covered area is Lynnwood, about 3.9 miles from the center of Bothell's covered ZIPs. Its median home was built in 1991, 6 years earlier than in Bothell. Bothell has 10 percentage points more detached single-family homes (61% vs. 51%), which changes how many projects are backyard decks versus compact townhouse decks. Owner-occupancy is 68% in Bothell compared with 57% in Lynnwood. Bothell's covered ZIP codes span about 32.9 square miles of land with roughly 54,294 homes — about 1,650 per square mile, a typical suburban density where most homes have usable backyards.