Deck builders in Mundelein, IL

Homes in Mundelein 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 Lake County overall (median 1983). Statewide, the median Illinois home was built in 1971. Among the 102 covered Illinois communities with Census data, Mundelein ranks #85 for oldest housing. In this ZIP code, 19% of homes were built before 1960, 22% between 1960 and 1979, 40% between 1980 and 1999, and 18% since 2000 — the single largest group dates to the 1990s.

The nearest NOAA climate station with 1991–2020 normals is Mundelein 4 Wsw, about 2 miles away. It records an average of 140 days a year with a low at or below 32°F — a long, hard freezing season. On roughly 86 of those days the temperature climbs back above freezing, so water in wood, soil and gaps between boards repeatedly freezes and thaws.

For Mundelein, that means footings must bear below the locally required frost depth to avoid heaving, and wood surfaces should be kept sealed so absorbed water doesn't split boards over winter. Synthetic decking tolerates freeze-thaw well but still needs the manufacturer's expansion gaps.

Snow is a major factor: the Mundelein 4 Wsw station averages about 43.1 inches a year. Framing has to carry snow load, stairs need a plan for winter use, and snow removal should be done with plastic-bladed shovels and ice-melt products the decking manufacturer allows.

Precipitation averages about 38.5 inches a year, falling on about 73 days with 0.1 inch or more — wet enough that drainage and flashing still matter, but dry spells also let wood surfaces dry out and check in the sun.

Summer heat is mild by comparison — average summer highs near 80°F and only about 11 days a year at 90°F or above — so board color can be chosen mostly on looks.

Budget, upkeep tolerance and sun exposure on your particular lot still decide the final choice between these options.

Mundelein has about 13,986 housing units across its covered ZIP code. 67% are single-family detached homes, 11% are attached homes such as townhouses and rowhouses, and about 22% are in buildings with two or more units. Roughly 74% of occupied homes are owner-occupied.

The mix of detached homes and attached or multi-unit housing in Mundelein 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 7,409 homes (53%) 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 4,033 homes (29%) 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 985 homes (7%) 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.

With about 140 freezing days a year, the building window in Mundelein is compressed. Design, drawings and permits are usually handled in winter so footings can go in as soon as the ground allows in spring, and finishes like stain are applied before nights turn cold in fall.

For Mundelein, IL, 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 Illinois is on our state page; local rules change, so the building department remains the authority.

The closest covered area is Lake Zurich, about 4.8 miles from the center of Mundelein's covered ZIPs. Its median home was built in 1988, 3 years later than in Mundelein. Mundelein has 20 percentage points fewer detached single-family homes (67% vs. 87%), which changes how many projects are backyard decks versus compact townhouse decks. Owner-occupancy is 74% in Mundelein compared with 88% in Lake Zurich. Mundelein's covered ZIP code span about 23.2 square miles of land with roughly 13,986 homes — about 603 per square mile, a low density that usually allows larger decks and freestanding designs.