ADU Construction - Design, Permits and Build Under One Contract

ADU Construction Done Right, Nationwide

ADU construction is a big bet on your property, and most owners who call us are nervous about it for good reason. They have heard about quotes that doubled, crews that disappeared for weeks, and permits that stalled with nobody taking responsibility. Lodgewick ADU Builders has handled ADU construction since 2010 as part of the Kingswell family of home-service companies, and we built the company around fixing exactly those problems. Start on the home page if you want the full picture of who we are.

Call (254) 602-5618

Every ADU construction project runs under The Kingswell Guarantee: a written price before work begins, a defined arrival window, a clean job site, and a written guarantee on the finished build. Russ Delmar leads our team. Call (254) 602-5618 and a live person answers, 24/7.

Key Takeaways

• You get a line-item written price before any ground is broken, and it does not change at the door.
• One contract covers design, permits, site work, framing, systems, and finishes.
• The 365-Day Done Right Promise is printed in every contract.
• A typical ground-up build takes four to seven months after permits are approved.

What ADU Construction Includes

ADU construction is the full process of building an accessory dwelling unit on your lot: a second, independent home with its own kitchen, bathroom, entrance, and utilities. It starts with the lot assessment and the plans, moves through permits and site work, and ends with a final inspection and a walkthrough where you check every room. Homeowners choose ground-up ADU construction when they want a permanent, code-compliant unit instead of a temporary structure or a partial conversion.

The scope is bigger than most people expect. Beyond the visible walls and roof, the job includes excavation, foundation, rough plumbing, electrical service, HVAC, insulation, drywall, flooring, cabinets, fixtures, and the connections to water, sewer, and power. We write all of it down, so nothing important hides behind the word “allowance.”

Foundation and Site Work

Good ADU construction begins below grade. Before we pour anything, we check soil conditions, slope, drainage, tree root zones, and the path equipment will take to reach the build site. A flat backyard with easy access is one project. A sloped lot with a tight side yard is another, and the price should say so.

Foundation Types

Most detached units sit on a concrete slab or a raised perimeter foundation. A slab is faster and cheaper, while a raised foundation helps on sloped lots and makes later plumbing repairs easier. We explain both, show the cost difference in writing, and recommend the one that fits your lot.

Drainage and Grading

A new structure changes how water moves across your property. We grade the site so runoff flows away from both the new unit and your existing home. It is a small line in the estimate that prevents a very expensive problem later.

Framing, Roofing, and Structure

Once the foundation cures, the framing crew goes up fast. Walls, floor system, roof structure, and sheathing follow the stamped plan set, and each stage is inspected before the next one starts. We build to standard material sizes wherever we can, which cuts waste and keeps the price where the written estimate said it would be.

Roof choice affects both cost and appearance. A simple shed or gable roof is cheaper to frame than a hip roof, and it often matches the main house just fine. We show you the numbers before you commit to a shape.

Plumbing, Electrical, and HVAC

An ADU adds real load to your property, so the systems matter as much as the structure. Plumbing needs a clean path to the sewer line, and the distance from the main house changes the trenching cost. Electrical work often means checking whether your main panel can carry the new unit or needs a service upgrade. Many of our builds use a ductless mini-split for heating and cooling, since it is quiet, efficient, and does not need a full duct run.

We keep kitchen and bathroom on a shared wet wall whenever the layout allows, because it can save thousands in plumbing. These are the kinds of choices we put in front of you early, in writing, before they turn into change orders.

Permits, Plans, and Inspections

ADU rules vary widely from one city and county to the next. Setbacks, height limits, parking requirements, and utility metering all differ, and building without approved plans can mean tearing out finished work. Our team pulls the permits and schedules every inspection as part of the written scope, so the build is legal from day one.

Design and permitting usually add two to four months before construction starts. We keep you updated through that stretch so you are never wondering where your file is sitting.

If you are not sure which type of project fits your goals, our room addition contractor service covers attached options that sometimes clear review faster than a detached unit.

ADU Construction Timeline

A standard ground-up ADU takes four to seven months of construction after permit approval. A smaller unit on an easy lot can finish near the short end. A two-bedroom unit with long utility runs lands near the long end. Weather, inspection scheduling, and material lead times all play a part, and we plan around them.

1. 1
   Site work and foundation. Excavation, trenching, forms, and concrete, usually three to five weeks.
2. 2
   Framing and dry-in. Walls, roof, windows, and doors, usually four to six weeks.
3. 3
   Rough systems and inspections. Plumbing, electrical, and HVAC rough-in, then insulation and drywall.
4. 4
   Finishes and final walkthrough. Cabinets, flooring, paint, fixtures, final inspection, and your walkthrough.

Stick-Built or Prefab ADU Construction

Not every lot calls for traditional framing. Panelized and factory-built systems from brands like Dvele, Boxabl, and Plant Prefab can cut weeks off the on-site schedule. They also bring their own requirements, such as crane access, foundation tolerances, and delivery windows. We have hands-on experience with these systems and will give you honest numbers for both paths.

If the lot is tight or the neighborhood has strict construction hours, prefab can be the smarter call. If you want custom layouts or the site has odd angles, stick-built usually wins. We tell you which one we would choose for your property and why.

Full ADU, JADU, or Conversion

Ground-up construction is the most complete option, but it is not the only one. A junior ADU, built inside an existing home, costs less and moves faster. A garage conversion sits between the two. We build all three types, and the right choice depends on your budget, your lot, and what you want the space to do.

If you already know you want a standalone unit, our second story addition contractor and sunroom builders pages cover related projects that some owners combine with an ADU on the same lot.

Signs You Are Ready to Build

• You have unused yard space and a clear reason for a second home. Rental income, family housing, or a home office are the most common goals, and each shapes the design.
• Your budget is set, even if the plan is not. We design to your real number instead of drawing something you cannot afford.
• A previous contractor stopped work or went quiet. We assess what was done right, what needs to be redone, and give you a written price to finish.
• You have a quote that feels too low or too vague. If it does not list site work, utilities, permits, and finishes, it is not a real price.

Our ADU Construction Process, Step by Step

1. 1
   Phone consultation. Call (254) 602-5618 and a live person answers. We talk through your goals, budget range, and the basics of your property.
2. 2
   Lot assessment. We measure access, grades, utility locations, tree protection zones, and setback lines, then take photos and notes for the design.
3. 3
   Written estimate. A line-item price covering site work, structure, systems, finishes, permits, and the 365-Day Done Right Promise.
4. 4
   Design and permits. We produce the plan set, submit for approval, and order long-lead materials.
5. 5
   Construction and walkthrough. A uniformed crew builds to plan, cleans up daily, and walks you through the finished unit.

How Much Does ADU Construction Cost?

Why Homeowners Choose Lodgewick

We have been building since 2010, and our approach has stayed simple. Say the price before the work, show up in the window given, leave the place cleaner than found, put the guarantee in writing, and come back if it fails. Our technicians are background-checked and uniformed, so you always know who is on your property.

When you hire us you get one contract, one schedule, and one person to call. If a subcontractor runs late or an inspector flags something, that is our problem to solve, not yours.

Where We Work

Lodgewick ADU Builders serves homeowners across the United States through local crews operating under The Kingswell Guarantee. Every location is independently owned and operated, so your build is handled by a team that knows the local rules and answers to you directly. The written price, the arrival window, the clean job site, and the 365-Day Done Right Promise are the same everywhere we work.

Frequently Asked Questions About ADU Construction

Schedule Your ADU Construction Today

A written price, a real schedule, and a guarantee in writing before the first shovel hits dirt. That is how we have built ADUs since 2010. Call (254) 602-5618 now and a live person answers, 24/7. Tell us about your lot and your goals, and we will schedule a free on-site estimate with no obligation.

Written by Russ Delmar, Owner at Lodgewick ADU Builders, serving homeowners nationwide since 2010.