The homes and lots in West Boise
One- and two-story subdivision homes from the second half of the 20th century, on flat former farm ground between Cole Road and the Meridian line. A city case study describes the West Bench as made up largely of mid-to-late-century single-family homes, mostly one and two stories, and the streets bear it out: ranches, split-levels, bi-levels and two-story production houses on curving blocks, most under subdivision covenants. Boise's 2020 almanac groups the area into the West Bench planning area, with the Centennial, Glenwood Rim, West Bench, West Valley and Winstead Park neighborhood associations; West Valley alone covers 5.6 square miles. Decks built with these houses are now 20 to 50 years old, and a good share of them were added by owners after the builder left.
- HOA architectural review
Spaulding Ranch is a city-owned park site with its own local historic designation, listed on the National Register and designated locally in 1995; the subdivisions around it are not in a historic district. The ground is flat, well away from the Hillside Development Overlay and from the foothills IR1 wildfire zone. The HOA flag applies to the subdivisions, most of which run architectural review under recorded CC&Rs; older county-era parcels may have none. Boise's 12-inch deck permit threshold applies to every lot, and irrigation ditch easements cross many plats.
What a West Boise deck has to account for
- Replacement dominates. Pressure-treated builder and owner-built decks from the 1980s and 1990s show soft joist tops, loose guard posts and corroded hangers and nails, and many sit on footings that never reached Boise's 24-inch frost depth. When the frame fails a probe test, deck replacement in Boise on new footings is usually the durable fix.
- Split-level and bi-level houses put the main floor four to eight feet above the back yard. Any deck surface more than 30 inches above grade needs guards at least 36 inches tall under the 2018 IRC, with openings that will not pass a 4-inch sphere, and stairs need risers of 7¾ inches or less and treads of at least 10 inches. Older decks on these houses frequently fail one or more of those checks, so guards and stairs are often replaced even when the frame is sound.
- Ditches and pressurized irrigation cross many back yards. Laterals from the canal systems that watered the old farms still run along lot lines, and Idaho Code 42-1209 requires the written permission of the irrigation entity that holds an easement before anything encroaches on it. Inside the subdivisions, pressurized irrigation mains and the owner's sprinkler lines are located and flagged before footings are dug.
- Covenants usually cover color, material, height and placement, and second-story decks that look into neighbors' yards draw the most attention. Committees in the area typically want a site plan, elevations and samples; written approval comes before building, and what Treasure Valley HOAs ask for in a deck submittal lists what a complete packet includes.
- Shade is thin on the newer streets. The city's 2020 almanac measured tree canopy at 19 percent in West Valley and 16 percent in Centennial, against 14 percent citywide, but the newest blocks have young trees or none. West- and south-facing decks take the full afternoon sun, so lighter capped boards and a pergola or cover make a July evening usable; attached covers need a Boise permit at any size.
- Hot tubs change the structure. Many West Boise owners add a spa to an existing deck, but the AWC DCA 6 prescriptive guide that most deck framing tables follow excludes hot tub loads, so a tub on a deck needs its own engineered support or a separate pad. We size that before the deck is designed rather than reinforcing afterward.
- Permits move faster with complete drawings. Boise's residential checklist for deck submittals calls for a site plan, framing plan, elevations and a section from footing to rail, notes that online review typically takes about two weeks, and requires stamped engineering for decks more than six feet above grade. Second-story decks on two-story homes often cross that six-foot line.
- Material choice usually comes down to maintenance against budget. Composite decking on Boise homes skips the yearly stain and holds up to UV, while pressure-treated wood costs less up front and suits a low deck that will be refinished regularly. Our cost calculator compares the two at your deck's size.
- Ground-level decks replacing lawn are popular on flat West Boise lots. A platform kept 12 inches or less above grade needs no Boise building permit, but it still has to respect setbacks and HOA rules, and the sprinkler heads and lines under it have to be capped or rerouted first so the frame does not sit in irrigation water all summer. A gravel base with landscape fabric under the joists keeps weeds down and lets water drain.
- The ledger connection depends on the siding. Many West Boise houses have lap siding on the back and a brick or stone wainscot on the front; the 2018 IRC does not allow a deck ledger on masonry veneer, so a deck that wraps toward a veneered wall gets its own posts and beam there. Where the ledger goes on lap siding, the siding is cut back, the ledger is through-bolted to the rim joist and the joint is flashed so water cannot collect behind it.
- North-facing decks hold winter longer than people expect. Boise averages 17.6 inches of snow and 16 days a year that never climb above freezing, and a deck in the shadow of a two-story house can keep packed snow and ice for weeks after the south side is clear. Boards with a textured, capped surface, a stair placed on the sunnier side and composite-safe ice melt instead of rock salt make that side of the house easier to live with, and the frame is sized for Boise's 20 psf ground snow load.
Around: Spaulding Ranch · Boise Towne Square · Maple Grove Road · Five Mile Road · Ustick Road · Fairview Avenue · Charles F. McDevitt Youth Sports Complex
West Boise deck questions
- Is it time to replace the deck on my 1990s West Boise home?
- Often, yes. Thirty-year-old pressure-treated decks usually show soft joist tops under the boards, loose guard posts and rusted hangers, and many were built on shallow footings. If the frame checks out, new boards and guards can buy time; if not, a full replacement on 24-inch footings is the durable fix.
- Does my West Boise HOA have to approve a new deck?
- Most West Boise subdivisions have CC&Rs requiring architectural approval of exterior changes. Expect the committee to review size, height, color and materials, and get the approval in writing before building, then build what was approved; changes in the field can put the deck out of compliance with the covenants. The HOA packet and the Boise permit can be prepared from the same drawings.
- Can a deck go over an irrigation easement in West Boise?
- Not without written permission from the irrigation entity that holds it, which Idaho Code 42-1209 requires, and an unapproved structure that interferes with the ditch can be removed at the owner's expense. We check the recorded plat, locate the lateral and any pressurized irrigation lines, and keep footings, stairs and the deck itself outside the easement lines.
- How tall do guards need to be on a split-level deck in West Boise?
- Under the 2018 IRC that Boise enforces, guards are required where the deck surface is more than 30 inches above grade, must be at least 36 inches tall, and cannot have openings that pass a 4-inch sphere. Stair guards can be 34 inches. Many split-level decks built decades ago have shorter guards or wider gaps and need new railing even if the frame is sound.
- Can I put a hot tub on my existing West Boise deck?
- Not on a standard deck frame without checking. The prescriptive deck guide most framing is based on excludes hot tub loads, so a filled tub needs engineered framing and footings or its own pad beside the deck. We design the support for the specific tub's filled weight and footprint before anything is ordered.
- How long does a deck permit take in West Boise?
- Boise's checklist says online review typically takes about two weeks for a complete residential submittal, and HOA review runs separately. Incomplete drawings are the usual cause of delay, so we submit the site plan, framing plan, elevations and footing-to-rail section together, with stamped engineering when the deck is more than six feet above grade.
Sources
- City of Boise — Spaulding Ranch Historic District
- City of Boise — West Bench planning area almanac (2020)
- City of Boise — West Bench townhomes case study
- Idaho Code § 42-1209 — Encroachments on easements and rights-of-way
- 2018 IRC (Idaho) — Chapter 3, guards and stairs
- American Wood Council — DCA 6 prescriptive deck construction guide
- City of Boise — #406 Residential Addition, Alteration & Accessory Building checklist (July 2025)
- City of Boise — Neighborhood Data Almanac (March 2020)
- City of Boise — Residential Construction guide
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