Permit-Ready Home Addition
Drawings for Lone Tree, CO

Expand your home with a permitted room addition, second story, or family room extension. We deliver complete, code-compliant drawing sets for Lone Tree's building department — 14-day money-back guarantee.

Review My Project Free → Addition FAQ ↓

14-day money-back guarantee · permit-ready delivery

Typical Cost Range
$150–$400/sqft
CO market estimate
Drawing Package
Free review first
local architects: $3,000–$10,000+
Plan Check Timeline
~8 weeks
Lone Tree estimate
Additions Permitted
Yes
CO building code

What Lone Tree Homeowners Need to Know Before Submitting

Size & Zoning Rules

Any new square footage added to your Lone Tree home counts against the same zoning envelope that governs ADU size, meaning large additions may affect your ability to add a future ADU. Lone Tree's current ADU size cap is 800 sq ft — within the typical range for most floor plan configurations.

Lone Tree does not impose an owner-occupancy requirement, so you can rent both the main home and any ADU or conversion as investment units.

If the addition creates a second unit or is later converted to a rental, Lone Tree's ADU market supports approximately $2,328/month for a 2-bedroom unit.

Permit Process & Fees

Building Division of the City of Lone Tree permit fees for this project type typically range from $2,009 to $3,488 depending on project valuation and scope.

Addition permit packages submitted to Building Division of the City of Lone Tree must include a site plan, floor plans, all four elevations, an electrical plan, and energy compliance documentation — plus stamped structural drawings are always required for any load-bearing elements, second-story work, or new foundation.

Visit Building Division of the City of Lone Tree ↗

⚠ Common Pitfall in Lone Tree

Almost every lot in Lone Tree sits inside a Douglas County-approved planned unit development (PUD) with its own HOA design review board, and those boards often have stricter setback and roofline-matching rules than the city's own zoning code — meaning your ADU can meet every city requirement and still get rejected until you resubmit revised elevations to the HOA. Because short-term rentals aren't allowed here, the city will also ask you to sign an affidavit confirming the unit is for long-term family or tenant use, which some lenders want to see before they'll finance the build. On top of that, Lone Tree runs water and sewer through the Willow Creek or Acres Green metro districts depending on your neighborhood, so you'll need a separate tap and service confirmation letter from that specific district before the Building Division will stamp your plans.

Expert Verdict — Marcus Reid, Licensed Designer

"In my experience, both that timeline and cost-per-square-foot figure are missing here entirely, which tells me they're likely relying on state-level estimates rather than actual Lone Tree data — I'd call the Building Division directly and get two or three local contractor quotes before penciling in a budget or schedule. With HOA coverage this high at 80%, what the data doesn't show is that your HOA's design review can add weeks to your timeline independent of whatever the city quotes you."

Market Context

Lone Tree has a median home value of $780,000. Comparable renovation projects in this market typically add 28% to resale value.

Neighborhoods in Lone Tree with the strongest home addition and resale value potential include Heritage Hills, Carriage Club, Montecito at RidgeGate, RidgeGate, McArthur Ranch. Gated luxury SFH enclave within walking distance of the Lone Tree light-rail station and Park Meadows, driving strong executive-rental demand.

Permit Process

Permit applications are reviewed by the Building Division of the City of Lone Tree. Permit fees in Lone Tree range from $2,009 to $3,488 depending on project scope.

Lone Tree falls within Seismic Design Category B, which affects structural requirements for any new addition tying into the existing structure.

Local Home Addition Lenders in Lone Tree

These lenders offer HELOC, construction, and renovation loans for home addition projects in Douglas County. Compare terms before committing.

Elevations Credit Union
Construction loan

Colorado-based credit union financing primary residences, second homes, investment properties, and remodels — usable for ADU construction; also offers a separate Investment Property HELOC up to $250,000 and 75% LTV.

Visit Lender ↗
Westerra Credit Union
Construction loan

Denver-metro Colorado credit union offering a One-Time Close Construction-to-Permanent loan that streamlines financing for new home construction or renovation projects (ADU-suitable).

Visit Lender ↗
Climb Credit Union
HELOC

Colorado credit union HELOC starting as low as 6.25% variable with a 10-year draw period and 15-year repayment, plus an Interest-Only HELOC option — usable to fund ADU builds.

Visit Lender ↗
Community Banks of Colorado (CoBnks)
Construction loan

Colorado community bank offering construction financing up to 80% of project costs (up to 90% with mortgage insurance on construction-to-permanent) with flexible terms and lot equity counted toward down payment.

Visit Lender ↗
Bank of Colorado
Construction loan

Colorado-based bank offering a Single-Close Construction Loan with 5/1, 7/1, and 10/1 ARM or fixed-rate (5/7/10-year) options, designed to streamline financing through construction.

Visit Lender ↗

Build With A Plan is not affiliated with these lenders. Always compare rates and consult a mortgage professional.

Vetted Home Addition Contractors in Lone Tree

We draw the plans. These contractors build the addition. Independent — no referral fees paid or received.

Jackson Design Build
All★ 5 (34)
(720) 729-3880
View Contractor ↗
Mark Hammer Construction LTD
Home addition★ 4.8 (41)
n/a
View Contractor ↗
Earthwood Custom Remodeling, Inc.
Home addition★ 5 (42)
n/a
View Contractor ↗
Velocity Built, LLC
Home addition★ 5 (48)
n/a
View Contractor ↗

Build With A Plan provides drawings only. We are not affiliated with these contractors and do not receive referral fees.

What Will Lone Tree Let You Add?

Setbacks, lot coverage, and height limits decide your addition before a single line is drawn. Send us the address and we’ll tell you what’s actually approvable — free, before you commit to a design.

  • Maximum footprint your lot and setbacks allow
  • Lot-coverage and height limits in Lone Tree
  • Whether your addition triggers structural or energy upgrades
  • Realistic plan-check timeline for your project
  • A straight answer within 48 hours

Review My Project — Free

Takes 60 seconds. We'll deliver your personalized report within 48 hours.

100% free. No credit card. No obligation. Results in 48 hours.

What's Included in Your Lone Tree Home Addition Package

Site Plan
Existing footprint, proposed addition, setbacks from property lines — formatted for Lone Tree submittal
📐
Floor Plans
Existing and proposed floor plans showing addition square footage, room labels, and dimensions
🏠
Elevations (4 sides)
Exterior views of the completed home showing how addition integrates with existing structure
Electrical Plan
New circuits, outlets, switches, and lighting for added square footage per NEC code
☀️
Energy Compliance
Title 24 Part 6 mandatory for all additions in CO — included in every package
🔩
Structural (Standard+)
Stamped structural drawings for foundations, load-bearing walls, beams, and roof framing

What's in Your Lone Tree Home Addition Package

One-time fee, no retainer, no hourly billing — your exact scope and price confirmed on a free call.

Starter
The core permit set. Priced on your free call.
  • Site plan
  • Floor plans (existing + proposed)
  • All 4 elevations
  • Electrical plan
  • Title 24 energy compliance
  • PDF + DWG delivery
  • 10 business day turnaround
Check My Eligibility →
Most Popular
Standard
Adds stamped structural. Priced on your free call.
  • Everything in Starter
  • Stamped structural drawings
  • Foundation plan
  • Roof framing plan
  • Window & door schedules
  • 1 round of revisions
Check My Eligibility →
Best Value
Premium
Full package, fastest turnaround. Priced on your free call.
  • Everything in Standard
  • 3D rendering
  • Cross-section details
  • Material specifications
  • HOA submission package
  • 2 rounds of revisions
  • Priority 5-day turnaround
Check My Eligibility →

Your Addition Drawings in 3 Steps

01

Submit Your Project Details

Share your property address, existing floor plan (if available), and the addition scope. We assign your project coordinator within 4 business hours.

02

We Draft Your Drawings

Our team designs your complete addition drawing set — engineered for Lone Tree's building department requirements and CO CBC code. Delivered in 10 business days.

03

Submit to Your Building Dept

Download your complete package and submit to Building Division of the City of Lone Tree. We support plan check corrections at no extra charge.

Lone Tree Home Addition FAQs

Do I need a permit for a home addition in Lone Tree? +

Yes — any structural addition to your home in Lone Tree requires a building permit. This applies to room additions, second-story additions, sunrooms, and attached garages. You'll need permit-ready drawings before the building department will accept your application. Our packages are formatted specifically for Lone Tree's submittal requirements.

How much does a home addition cost in Lone Tree? +

Home additions in Lone Tree typically cost between $150–$400 per square foot depending on the scope, finishes, and structural complexity. A 600 sq ft addition ranges from $90,000 to $240,000. Second-story additions cost more than ground-floor extensions due to structural requirements. Contact us to discuss drawing package options for your project.

What drawings are required to permit a home addition in Lone Tree? +

Lone Tree's building department requires: a site plan showing the addition's footprint and setbacks, floor plans for all affected levels, all four exterior elevations, an electrical plan, and energy compliance (Title 24 in California). Structural plans stamped by a licensed engineer are required for any load-bearing elements — included in our Premium package.

How long does the permit process take for a home addition in Lone Tree? +

Plan check in Lone Tree typically takes 8 weeks for home additions. Additions with structural components may require additional review. Complete, code-compliant drawings significantly reduce correction cycles — each cycle adds 3–6 weeks. Our drawings are engineered to pass on the first submittal.

What setbacks apply to home additions in Lone Tree? +

Lone Tree enforces minimum setbacks from property lines for all additions: typically 4–5 ft side setbacks and 5 ft rear setbacks, though these vary by zoning district and lot size. Your addition must stay within the buildable envelope. Our site plan documents existing and proposed setbacks and flags any zoning variances required.

Do I need structural drawings for a home addition in Lone Tree? +

Yes, for most additions. Any load-bearing walls, new foundations, second-story construction, or roof structure changes require stamped structural drawings from a licensed engineer. California's CBC (California Building Code) and seismic requirements make structural plans mandatory for most addition types. Our Standard and Premium packages include stamped structural drawings.

How much do home addition drawings cost in Lone Tree? +

Our permit-ready home addition drawing packages for Lone Tree include everything your building department requires — floor plans, elevations, structural, and energy compliance. Every package is engineered for CO code compliance and formatted for Lone Tree's building department. 14-day money-back guarantee.

Will a home addition increase my home's value in Lone Tree? +

In Lone Tree, where median home values are approximately $780,000, a permitted home addition adds square footage that appraisers value as part of the home's gross living area. Return on investment varies by addition type — master suite additions, family room expansions, and additional bedrooms typically recoup 50–75% of project cost in appraised value in CO markets.

Can I add a second story to my home in Lone Tree? +

Second-story additions are permitted in most Lone Tree residential zones, subject to height limits and design review requirements. California generally requires ministerial permit approval, but some cities impose design compatibility or neighborhood compatibility review for second stories. Our drawings cover all levels including foundation upgrades, shear walls, and roof framing required for vertical additions.

Nearby Cities

Castle Rock Parker Castle Pines Denver

From the Blog

Home Addition: The Complete Guide for Homeowners (2025) Read the article → Home Addition Cost: A Full Price Breakdown by Type and Square Footage (2026) Read the article →

Also Available in Lone Tree

Adding an ADU instead? See our ADU design service.

View ADU Design →

Ready to Move Forward With Your Lone Tree ADU?

You've evaluated your property's eligibility, run the numbers, and seen the market data. The next step is getting permit-ready architectural drawings to submit to Building Division of the City of Lone Tree.

🏛️

Hire a Local Architect

$3,000 – $8,000

  • ·4–8 weeks turnaround
  • ·Fully custom design
  • ·In-person consultations
  • ·Direct line to architect

Best for: Highly customized projects, complex sites, or homeowners who want an ongoing designer relationship.

Practical Choice
📐

Build With A Plan

Quoted on your free call

  • 10 business days turnaround
  • Permit-ready, CA-code compliant
  • Same documents your building dept needs
  • 14-day money-back guarantee

Best for: Homeowners who want fast, affordable permit-ready drawings for a standard ADU build.

Both options produce permit-ready architectural drawings accepted by Building Division of the City of Lone Tree. The right choice depends on your timeline, budget, and how much customization your project requires.

See Our Drawing Packages ↓ Common Questions ↓
Not sure which one you need? Take the Free Quiz → Not sure on numbers? Run the Interactive Cost Calculator →