How Much Does Home Addition Cost in Denver, CO?

Updated March 2026 · Denver metro area · Based on BLS wage data and local market costs

Denver Average Cost (per project)

Low

$21,000

Average

$47,250

High

$84,000

BudgetMid-RangePremium

Itemized Cost Breakdown

Estimated for Addition size (sq ft): 300 sqft · Mid-Range tier · Local cost index: 1.05x

Line Item	Low	Mid	High
Foundation Slab, crawlspace, or basement foundation	$3,150	$6,300	$9,450
Framing Walls, roof tie-in, headers, and sheathing	$3,780	$5,828	$7,875
Roofing New roof section tied into existing roof Shop Roofing Materials	$1,575	$3,150	$4,725
Exterior finish Siding, windows, and exterior trim to match	$2,520	$4,410	$6,300
Electrical New circuits, outlets, lighting, panel capacity	$1,575	$3,150	$4,725
Plumbing (if applicable) Water/drain lines for bath or kitchen addition	$0	$3,938	$7,875
HVAC extension Duct runs and tonnage increase for new space	$945	$2,048	$3,150
Interior finish Drywall, paint, flooring, trim, doors	$3,150	$6,300	$9,450
Permits & engineering Building permit, structural engineering, plan review	$1,050	$3,150	$5,250
General contractor overhead Project management, coordination, insurance	$2,520	$4,410	$6,300
Total Estimated Cost	$20,265	$42,683	$65,100

Costs adjusted for local market conditions. Actual prices vary based on project specifics, contractor, and material choices.

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Cost Calculator

Adjust project size and material tier to estimate your cost.

Addition size (sq ft)

60900

Material Tier

Your Estimated Cost

Low

$20,265

Average

$42,683

High

$65,100

View itemized breakdown

Item	Low	High
Foundation	$3,150	$9,450
Framing	$3,780	$7,875
Roofing	$1,575	$4,725
Exterior finish	$2,520	$6,300
Electrical	$1,575	$4,725
Plumbing (if applicable)	$0	$7,875
HVAC extension	$945	$3,150
Interior finish	$3,150	$9,450
Permits & engineering	$1,050	$5,250
General contractor overhead	$2,520	$6,300
Total	$20,265	$65,100

Estimates based on local cost data. Get quotes from licensed contractors for accurate pricing.

What Drives Home Addition Cost in Denver?

The average cost of home addition in Denver, CO is $47,250 per project. Most homeowners pay between $21,000 and $84,000, depending on the scope of work, materials selected, and contractor experience.

Construction of new living space added to an existing home.

Local Labor Costs

Construction workers in Denver earn an average of $25.3/hr — 11% above the national average. Labor typically accounts for 40-60% of total project cost.

Materials in CO are subject to 8.77% sales tax, which adds to the overall project cost. For a $47,250 project, expect roughly $1,658 in tax on materials alone.

Denver issued approximately 17,600 residential building permits in 2023, putting it in the upper range of US construction markets. High permit activity can mean busier contractors and longer wait times for scheduling.

Factors That Affect Cost

Square footage
Foundation type
Finishes
Plumbing/electrical
Permits
Roof tie-in
Contractor experience — Established contractors with strong reviews may charge 10-20% more
Local cost of living — Denver's cost index is 1.05x the national baseline

Best Time for Home Addition in Denver

Denver has cold winters with snow and dry, sunny summers. The building season is May through October. Spring snowstorms can delay early-season projects. High altitude affects concrete curing.

Best Months

May, Jun, Jul, Aug, Sep

Lower demand often means better pricing and faster scheduling.

Peak Season (Higher Prices)

Dec, Jan, Feb

High demand can add 10-20% to project costs.

Monthly Weather in Denver

Month	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Avg High	45°	48°	56°	62°	72°	83°	90°	87°	79°	66°	52°	44°
Avg Low	16°	19°	27°	34°	43°	52°	58°	57°	47°	35°	24°	16°
Rain (in)	0.5	0.5	1.3	1.7	2.3	1.8	2.2	1.8	1.3	1	0.8	0.5

Source: Open-Meteo historical data (2024)

Licensing & Permits in CO

Colorado does not require a state-level general contractor license. Denver and most jurisdictions require local contractor licensing. Plumbing, electrical, and mechanical trades require state licenses.

Verify a contractor's license at Colorado Department of Regulatory Agencies.