Deck Builderin Whittier, CA
A deck builder in Whittier first checks height and attachment: a wood deck not over 30 inches above grade, detached from the house and not serving an exit is exempt from a building permit, while an attached or taller deck needs one. Puente Hills lots add a hillside development plan, and fire zone and historic rules can change the boards.
Most Whittier backyards belong to the postwar tracts: 37.1 percent of the city's 31,200 homes date from the 1950s, and 88.8 percent from before 1980. A deck added to one of those houses meets original framing, an old stucco or siding wall for the ledger, and soil that termites already know. Near Uptown the houses are older still, with Craftsman, Victorian and Spanish revival homes sitting in four historic districts.
MDG Builders, CSLB #1040337, is a general contractor in Tarzana. We design the deck, put the permit questions to Whittier Building & Safety and schedule the trades, and licensed subcontractors do the framing, surfacing and railing, with their license numbers and insurance certificates open to your request. Materials, labor and sources are on our decks page, and the Whittier overview lists the other trades we manage here.
What Whittier's codes and the state residential code say about decks
Where decks permits come from in Whittier: City of Whittier Community Development Department, Building & Safety Division.
- A wood deck is exempt from a building permit only if it is not over 30 inches above the surrounding grade or finishes, is not attached to a structure, and does not serve any part of a means of egress (administrative provision 105.2). Any attached or higher deck falls under the building permit rule.
- Planning takes residential patio covers up to 600 square feet through the online Development Review Counter application, and the same list covers pools and spas and residential mechanical equipment. The page lists no online path for larger patio covers.
- Municipal Code 18.64.020 allows several intrusions into required yards, including uncovered porches and platforms, stairways and balconies, planter boxes, bay windows, and pool equipment placed within a fully enclosed structure. Covered structures are not on that list.
- Whittier's metal roofing rule has an exception for metal patio covers on the rear of the building when more than 50 feet from the street (Municipal Code 18.10.030(G)(1)(a)(ii)), and an R-1 lot's total building coverage including accessory buildings is capped at 40 percent (18.16.030(E)).
- In the H-R hillside zone, no building or structure can be built until a hillside development plan is approved, and the plan application must show all proposed retaining walls and protective fences with their location, height and material (Municipal Code 18.14.040 and 18.14.060).
Can you build a deck on a Puente Hills lot in Whittier's H-R zone?
Only after a hillside development plan is approved. Whittier's H-R zone, Municipal Code chapter 18.14, covers land on the City's 1979 Hillside and Biological Sensitivity maps, and no building or structure can go up there until the Planning Commission and City Council approve a plan. The plan application has to show every retaining wall and protective fence with its location, height and material, and it comes with a soils and geologic report. We did not open the maps, so ask Whittier Planning whether a lot is mapped.
The chapter bars building on major ridge lines and, without a geologic report, on mapped potential hazard areas. Grading is limited too: cuts and fills may be no higher than 20 feet or steeper than 2 to 1, and the share of a site that may be graded drops from 80 percent on gentle ground to 5 percent on slopes near 50 percent. State landslide zones cover 49 of 413 sample points inside the city (11.9 percent), and that figure is a point count, not a parcel count.
For a deck on posts over a slope, the footings are the first thing an engineer reads, because they stand in the ground that the geologic report describes. That is why a hillside deck is priced after a site visit, not by the foot.
Which deck boards are allowed near Whittier's Very High fire hazard areas?
That depends on whether the lot is mapped, and the answer is changing. Whittier was reached by the State's new fire hazard map for local responsibility areas on March 24, 2025. Sampling the County's copy of it at 413 evenly spaced points inside the city, 135 (32.7 percent) landed in the Very High zone, 14 in High, 18 in Moderate and 246 in Non-Wildland, while the City's hazard plan counts 2,373 of 23,414 parcels (10.1 percent) as Very High. Hills have big parcels, so the two figures differ. The City's fire severity page says the Council would consider an ordinance to adopt the maps, so ask whether that has happened for your address.
The plan puts the highest exposure north of Whittier Boulevard along the Puente Hills flank, where the Turnbull II fire of 1967, about 1,750 acres, burned near Whittier College. Section 18.14.080(G) states that every H-R property is in a high fire-risk area. Whittier also requires Class A roof coverings citywide under Municipal Code 15.18.010.
For boards, section R337.9.3 of the 2022 California Residential Code lists the decking surfaces allowed in wildland-urban interface areas: products tested to ASTM E2632 or E2726, ignition-resistant, fire-retardant-treated or noncombustible material. A UC extension summary said some composites tested did not meet the ignition-resistant definition, so confirm any product on the State Fire Marshal listing. We could not read Whittier's own wildland-urban interface chapter, 15.11, so ask the counter what it adds.
Can you build a deck in Whittier without a permit, and what is the largest deck allowed?
Sometimes. Section 105.2 of the City's administrative provisions exempts a wood deck only if it is not over 30 inches above grade, is not attached to a structure and does not serve any part of a means of egress. Anything attached to the house or higher than that falls under the building permit rule. We found no square-foot ceiling in that list; the 200 square foot line in the model residential code does not appear in it, so get the counter's answer in writing.
Zoning is separate from the permit. An R-1 lot needs a front yard of at least 20 feet, interior side yards of at least 5 feet and a rear yard of at least 5 feet, and buildings including accessory buildings may cover no more than 40 percent of the lot (Municipal Code 18.16.030). Section 18.64.020 allows uncovered porches and platforms to intrude into required yards, but covered structures are not on that list.
A pergola or patio cover is a different path. Planning takes residential patio covers up to 600 square feet through its online Development Review Counter application and lists no online route for larger ones. Metal patio covers get an exception from the metal roofing ban when they sit on the rear of the building and more than 50 feet from the street.
Deck repair in Whittier: when does a fix need a permit and an inspection?
When it touches structure. Section 105.2.2 says ordinary repairs need no application but cannot include removing a structural beam or load-bearing support, so swapping worn boards is routine and replacing a post, beam or stair stringer is not. The City exempts only unattached decks under 30 inches, which makes any repair to an attached deck worth a call to Whittier Building & Safety before lumber is ordered.
The usual failure point is the ledger where the deck meets the house. The 2022 California Residential Code, section R507.9, calls for a ledger of at least 2 by 8 pressure-treated lumber, flashing, hot-dipped galvanized or stainless fasteners and lateral hold-downs: two devices of 1,500 pounds within 24 inches of each end, or four of 750 pounds. Whittier's design table rates termite damage as very heavy, and UC's pest guide says drywood termites are common in Southern California decks and fences, so probe ledgers and post bases before deciding to patch.
When a permit exists, the City asks for inspections to be requested at least one business day ahead, and the stamped plans and job card must be on site for the inspector.
How high must a Whittier deck railing be, 36 inches or 42?
Forty-two inches, in the residential code section we read. Drop a deck's surface more than 30 inches above the ground within 36 inches of an edge, and the 2022 California Residential Code wants a guard at least 42 inches tall, with gaps too narrow for a 4 inch ball to pass. Below 30 inches, no guard is required, which is one reason low rear decks on flat tract lots stay simple.
That changes the design of a raised deck, a balcony or a second-story platform, where the guard becomes the first part to detail. Posts must be anchored to carry the load on the rail, and stair guards and handrails follow their own sections, so ask the plan checker which edition applies on the day of your application.
Can you add or replace a deck in one of Whittier's historic districts?
Possibly, with review. Whittier's four historic districts, Central Park, Hadley-Greenleaf, College Hills and Earlham, require a certificate of appropriateness or a waiver for work that changes a building's physical appearance, and no permit is issued before one is in hand. Hadley-Greenleaf is mainly Craftsman bungalows with Victorian cottages and Spanish revival homes, generally two stories or less and covering less than half of their lots, while Earlham's period of significance runs from 1903 to 1940.
Section 18.84.180 lets the Secretary of the Historic Resources Commission waive review for small unseen additions when appearance does not change significantly. A low rear deck that cannot be seen from the street resembles that language, but the Secretary decides, and a deck that rises above a fence line is a different case. Owners of landmarks and contributing homes can also apply for a Mills Act property tax contract under 18.84.300, which is worth asking about before original porch or deck features are removed.
How much does a deck builder charge in Whittier, wood or composite?
We found no Whittier study with a stated method, so we use the Los Angeles figures behind our decks page: pressure-treated wood at $45 to $75 per square foot and composite at $65 to $110, on a flat lot with an attached deck, before permits and engineering. A 16 by 20 foot deck is 320 square feet, which multiplies out to $14,500 to $24,000 in wood and $21,000 to $35,000 in composite.
The 2025 Cost vs. Value report from JLC and Zonda prices a defined 16 by 20 deck with a bench, planter, three steps and full railing at $18,419 in wood and $26,872 in composite in Los Angeles, with resale recouping 99.6 percent and 73.9 percent. Angi's October 2025 Los Angeles page and HomeGuide's February 2026 guide served as cross-checks. Confidence is medium for wood and medium to low for composite.
Hillside, second-story, rooftop and ipe decks get no per-foot number from us; they are priced by site visit. Wood is cheaper to build but needs more upkeep and termite attention, and Whittier's very heavy termite rating makes that more than a footnote. Our license check guide shows how to verify who holds the license, and framing falls under CSLB's C-5 class.
Deck photos from Whittier and nearby communities
Photos of decks around Whittier and its neighbors, from low rear decks and framing to posts, rails and boards. Tap a photo to enlarge it.
What decks costs around Whittier
These are the Los Angeles ranges behind our decks page, not a Whittier quote, and the subcontractor guide explains how the trades divide the work. Nearby pages: decks in Norwalk, decks in Downey, decks in Los Angeles, decks in Pasadena, concrete work in Whittier and flooring in Whittier.
| What it covers | Typical range |
|---|---|
| Pressure-treated wood deck | $45 to $75 per square foot |
| Composite deck | $65 to $110 per square foot |
| 16 by 20 foot wood deck (320 sq ft) | About $14,500 to $24,000 |
| 16 by 20 foot composite deck | About $21,000 to $35,000 |
| Hillside, second-story, rooftop and ipe decks | Priced by site visit |
| Permits and engineering | Quoted as separate lines |
Whittier deck questions, answered
Can I build a deck without a permit in Whittier?
Only a low, detached one. The City's exempt list covers a wood deck not over 30 inches above grade that is not attached to a structure and does not serve an exit. An attached or higher deck needs a building permit. Zoning setbacks apply either way, so confirm your plan with Building & Safety before you buy lumber.
What is the largest deck without a permit in Whittier?
The City's list sets no area figure we could find. The model residential code exempts a deck of 200 square feet or less that is under 30 inches, detached and not serving a door, but Whittier's text does not repeat that line. Get the counter's answer in writing before you build.
How much would a 16x20 deck cost in Whittier?
Roughly $14,500 to $24,000 in pressure-treated wood and $21,000 to $35,000 in composite, from Los Angeles ranges of $45 to $75 and $65 to $110 per square foot. Cost vs. Value 2025 shows $18,419 and $26,872 for a defined version. Permits and engineering are extra, and a site visit sets the price.
How much would a 20x20 deck cost in Whittier?
Multiplying 400 square feet by Los Angeles ranges gives about $18,000 to $30,000 in wood and $26,000 to $44,000 in composite. That is arithmetic on medium to low confidence sources, not a quote. Stairs, railing, a hillside lot, permits and engineering move the price, so an on-site measurement settles it.
Is it cheaper to build a wood deck or composite deck in Whittier?
Wood costs less to build. Los Angeles figures put it at $45 to $75 per square foot against $65 to $110 for composite, and Cost vs. Value 2025 shows the same gap. Composite recoups less at resale in that report, 73.9 percent against 99.6 percent, but wood needs more upkeep and termite checks.
Is deck railing 36 or 42 inches in Whittier?
Forty-two inches in the 2022 California Residential Code section we read. A guard is needed once the surface is more than 30 inches above grade within 36 inches of an edge, and baluster gaps must stop a 4 inch ball. Below 30 inches no guard is required. Confirm the edition with the plan checker.
What decking is allowed in Whittier's fire zones?
In wildland-urban interface areas the 2022 California Residential Code allows ignition-resistant, fire-retardant-treated, noncombustible or specially tested boards. Many Puente Hills lots north of Whittier Boulevard may fall in a Very High zone, and every H-R lot is called high fire risk. Check the CAL FIRE viewer and ask the counter whether the 2025 map is adopted.
Do I need a permit for deck repair in Whittier?
Replacing boards is ordinary repair, but replacing a post, beam, ledger or stair stringer is not, because section 105.2.2 excludes removing structural supports from ordinary repair. Any attached deck is worth a call to the Building counter first. Ask before ordering lumber, since inspections need stamped plans on site.
What license does a deck builder need in Whittier?
A deck is framing, so a B general contractor or a C-5 framing and rough carpentry license applies, unless the job costs $1,000 or less in labor and materials and needs no permit. Look up the number on the CSLB site. We found no CSLB statement on which class covers composite surfacing, so ask your bidder.
Can I add a deck in a Whittier historic district?
Yes, with review. Central Park, Hadley-Greenleaf, College Hills and Earlham need a certificate of appropriateness or waiver for work that changes appearance, and no permit issues before it. A low rear deck unseen from the street resembles the small unseen additions a waiver can cover, but the Commission's Secretary decides, so ask first.
Send the address and a photo of the yard
Tell us how high the deck would sit, whether it touches the house, and whether the lot is flat or on the Puente Hills side, so the permit checks come first.