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CASTLE PINES SERVICES

Castle Pines ADU / backyard cottage — local feasibility & estimate

ADU Feasibility Consultation, $350

Compare both studies

Exploring a backyard ADU in Castle Pines? Autotelic helps assess feasibility against lot, setbacks, HOA, and local rules—then provides a clear estimate and build path with one team. No fake zoning envelopes. No invented prices or license claims.

What Castle Pines requires

ER — Front Setback (min): 25' ER

See full local requirements ↓
  • Full Design Lifecycle
  • Construction & Tenant Finish
  • Smart Home · A/V · Edge Compute
ADU / Backyard Cottage

Build an income-producing unit in your backyard

Book an ADU feasibility study

Two fixed-price studies, booked online before you pay for design: a site visit with a go/no-go read on your lot, or a written report you can take to a lender.

Pay when you book. We confirm within 24 hours or refund you in full.

  • ADU Feasibility Consultation

    An on-site review of your lot against local ADU zoning, setbacks, and utility access.

    Pay when you book · morning (8–12) or afternoon (12–4)

    What's included

    An on-site review of your lot against local ADU zoning, setbacks, and utility access. You get a verbal go/no-go read plus a one-page summary of constraints and next steps.

  • ADU Feasibility Package

    Site visit plus a written feasibility report: local ADU zoning check, buildable envelope sketch, utility routing notes, and a preliminary budget.

    $475 deposit to book, the rest when the work is done · morning (8–12) or afternoon (12–4)

    What's included

    Site visit plus a written feasibility report: local ADU zoning check, buildable envelope sketch, utility routing notes, and a preliminary budget. A documented go/no-go you can take to a lender.

Studies for additions, custom homes and commercial space

FREE PLANNING TOOLS

Both tools are free and take a couple of minutes — start in either one.

Local Service

ADU / Backyard Cottage Services in Castle Pines, Colorado

Autotelic provides professional ADU / backyard cottage services throughout Castle Pines and the surrounding Douglas County area. Accessory dwelling unit construction across the Denver metro — detached new builds, garage conversions, and basement conversions compliant with Colorado HB 24-1152. One veteran-owned design-build team runs the full Denver sequence under a single contract: zoning verification and concept design, municipal zoning and building permit reviews, then construction and inspections through certificate of occupancy. Whether you're in Castle Pines (south Douglas County) or nearby communities, our team delivers quality workmanship, licensed and insured.

Permit Thresholds

Castle Pines permit thresholds

Code reference
The City of Castle Pines Building Department requires building permits for various residential remodel projects to ensure compliance with the 2021 International Building Code/International Residential Code and the 2023 National Electrical Code.
Code reference
1-Stop Permits are for projects that do not require drawings for a plan review.
Code reference
Instead, the requirement for a permit is based on the *type* of work being performed, as detailed in the lists for 1-Stop Permits and Plan Review Permits.
Code reference
The City of Castle Pines operates under the 2021 International Building Code/International Residential Code and the 2023 National Electrical Code.
Code reference
### Taxes and Fees (Based on 2026 Fee Schedule where available, or most recent provided)
Code reference
For example, according to the 2025 and 2026 Fee Schedules:
Code reference
For projects valued from $1.00 to $500.00, the fee is $42.00 (2025/2026).
Code reference
For projects valued from $501.00 to $2,000.00, the fee is $42.00 for the first $500.00, plus $5.45 for each additional $100.00 or fraction thereof (2025/2026).

Codes are amended regularly — verify current requirements with **The City of Castle Pines Building Department (part of the City’s Community Development department) issues residential building permits.

Zoning & ADU

Castle Pines zoning & ADU quick facts

ER — Front Setback (min)
25'ER
ER — Side Interior Setback (min)
25'ER
ER — Side Setback Abutting Street (min)
25'ER
ER — Rear Setback (min)
25'ER
ER — Building Height (max)
35'ER
ER — Acreage bands
§610 other-street: <2.3 ac sides 15'; 2.3+ sides 25'. Regional/major arterial front is 100'. Shown is the 2.3+ acre row.ER
Estate Residential — Front Setback (min)
25'Estate Residential
Estate Residential — Side Interior Setback (min)
25'Estate Residential
Castle Pines Zoning Ordinance ER setback standards (§307 A-1 / §610 ER / §612 / §309 Building Height) — effective 2019-09-01 · Castle Pines Zoning Ordinance Estate Residential setback standards (§307 A-1 / §610 ER / §612 / §309 Building Height) — effective 2019-09-01Source: castlepinesco.gov

Codes are amended regularly — verify current requirements with **The City of Castle Pines Building Department (part of the City’s Community Development department) issues residential building permits.

A recent build

Backyard ADU in Denver

Denver · 2026

Status
Under construction — 2026
Managed on
Buildbot — Autotelic’s own PM platform
  • Architecture, site plans, and full MEP design completed in-house
  • Permits pulled — electric and plumbing rough-ins permitted and underway
  • Spray-foam insulation and exterior work in progress
  • First project managed end-to-end on Buildbot, Autotelic’s construction-PM platform

A ground-up backyard ADU in Denver — designed, permitted, and now under construction by Autotelic, and the first project managed end-to-end on Buildbot, Autotelic’s own construction-management platform.

Energy Code

Castle Pines energy code quick facts

Code reference
The City of Castle Pines, Colorado, operates under the 2021 International Energy Conservation Code (IECC) as its currently adopted energy code.
Code reference
While an earlier ordinance (Ordinance No. 16-08) adopted the 2015 IECC, state law (House Bill 22-1362) mandates that jurisdictions updating other building codes between July 1, 2023, and June 30, 2026, must adopt and enforce the 2021 IECC or an equivalent or more stringent code.Ord. No. 16-08
Code reference
The City of Castle Pines currently enforces the 2021 International Building Code (IBC) and International Residential Code (IRC), which would trigger the 2021 IECC adoption requirement.
Code reference
Castle Pines is located in Climate Zone 5B.
Code reference
Here are key prescriptive requirements from the 2021 IECC relevant to remodels and additions in Climate Zone 5B:
Code reference
### Key Prescriptive Requirements for Remodels/Additions (2021 IECC, Climate Zone 5B)
Code reference
The following requirements apply to new construction and additions, and often to portions of existing buildings that are altered, as per the 2021 IECC and generally apply to residential applications.
Requirement
R-60
Ord. No. 16-08

Codes are amended regularly — verify current requirements with **The City of Castle Pines Building Department (part of the City’s Community Development department) issues residential building permits.

Service Area

Serving Castle Pines and Douglas County

We serve Castle Pines, CO and all surrounding Denver metro communities. Our team is based in Denver and operates throughout the Front Range, from Castle Rock to Longmont and everywhere in between. Contact us for a free estimate on your Castle Pines project.

FAQ

ADU feasibility FAQ

How much does ADU Feasibility Consultation cost in Castle Pines?

$350.

How do I book?

Press Book next to the job, pick a date and a morning (8–12) or afternoon (12–4) window, and pay in full. We confirm within 24 hours or refund you in full.

Can I build an ADU on my lot?

It depends on lot size, setbacks, HOA rules, and Castle Pines’s code. Autotelic helps assess feasibility—we do not invent zoning envelopes or guarantee permit outcomes.

Is the online sizing tool a permit determination?

No. Lot-aware sizing on /adu/ is illustrative only and is not a permit determination. A clear estimate and local review come next.

What happens after I start an estimate?

You move from feasibility into a clear estimate with the same design-build team, then permit coordination and build with a licensed Denver-metro crew when you proceed.

What will an ADU cost?

The lot lookup is free. Our ADU cost page shows planning ranges for a detached backyard cottage; your lot, utility connections and finishes affect the price. Start an estimate for your project, or call (720) 287-7958 to talk it through. A fixed-price build proposal comes after feasibility.

How long does an ADU project take?

First we check your lot and agree on the scope. Then come design and drawings, city permit review, and construction with inspections. Your lot, utility connections, design changes and the city’s review schedule affect the timing. Your proposal includes a project-specific schedule before you commit to the build. A consultation booking is the first planning conversation, not a construction start date.

Who builds the ADU?

Autotelic’s local design-build team takes your project from the first concept through an estimate, permits and construction. You have one team to talk to along the way.

Do you handle ADU permits and inspections?

Yes — ADU permitting is municipal, and we manage zoning review, permit application, and every inspection through certificate of occupancy.

Detached, attached, or garage conversion — which is right?

Each has different zoning, cost, and site implications. We design all three and recommend based on your lot, budget, and how you plan to use the unit.

How small a lot can support an ADU?

Smaller than most people assume — many Front Range single-unit lots that owners write off can carry a detached unit, and each city sets its own minimum lot size, setbacks, and building coverage. Whether your district’s standards leave room for a backyard cottage — or point you toward a garage or basement conversion instead — is exactly what the feasibility check answers for your address.

What is the ADU permit process?

Two municipal reviews run in order: a zoning review confirming the unit fits your district’s standards, then a building permit review of the construction documents, with inspections during the build and a certificate of occupancy at the end. Colorado HB 24-1152 now requires most Front Range municipalities to allow ADUs on single-unit lots, and we confirm how your city implements it as the first step of feasibility.

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Survey

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03

Build

04

Verify

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