Maryland ADU Builders & Prefab Options: Modular, Site-Built & Turnkey Companies

There is no single “best” Maryland ADU builder—and “prefab” can mean very different things. A homeowner may be comparing a local design-build contractor, a state-regulated modular dwelling, a pre-cut building kit, or a mobile/tiny product that still needs a lawful Maryland approval path before it can become a permanent ADU.

This guide compares companies that publicly state they serve Maryland ADU, modular, or small-home projects. Inclusion is not an endorsement or paid ranking. We do not rank companies based on payment, and we do not treat a marketing claim such as “turnkey,” “certified,” or “prefab” as proof that a specific product can be permitted on a specific Maryland lot.

Last verified: September 6, 2026. Company service areas, licenses, pricing and product offerings can change. Re-check contractor licensing, insurance, model approval and local permit eligibility before signing a contract or paying a deposit.

Quick answer: which ADU delivery model fits your project?

Delivery modelWhat you are really buyingBest fitMain question to resolve
Local design-build / site-builtOne team may handle feasibility, drawings, engineering, permits and conventional construction.Irregular lots, custom designs, additions, conversions, difficult utility/site conditions.Exactly which design, permit, utility and site-work items are included in the contract?
Turnkey ADU specialistA coordinated ADU-focused process, usually design + permitting + construction.Homeowners who want one accountable project lead.Does “turnkey” include survey, civil work, utility upgrades, septic/well, foundation, landscaping and final approvals?
Industrialized / modular dwellingFactory-built dwelling sections regulated through Maryland’s industrialized-building program, then installed on a permanent foundation.Repeatable designs and projects where factory construction can simplify part of the build.Who is the approved manufacturer, what is the Maryland model approval path, and who handles local site/foundation work?
Prefab / pre-cut kitA materials/structural package delivered to the site; it is not automatically a completed dwelling.Owners with a qualified local builder and a clear permit path.What is excluded from the kit price—foundation, labor, MEP, permits, finishes, utilities, crane/delivery?
Mobile / tiny productA transportable product whose legal classification may differ from a state-regulated modular dwelling.Only after the exact product classification and local dwelling approval path are confirmed.Can this exact model legally become a permanent dwelling/ADU on your property?

Maryland ADU builder & prefab comparison

The table below reports what each company publicly states on the pages we reviewed. “License published” means the company publishes a Maryland license or registration number on its own site; homeowners should still verify current status with the issuing authority.

CompanyModelMaryland scope publicly statedPermit / design scopePublic licensing detailPricing transparency
Makara ADUADU-focused design-build / turnkeyMontgomery, Anne Arundel, Howard and Frederick counties plus multiple Maryland citiesCompany states feasibility, plans, permitting, engineering and construction are availablePublishes MHIC 151479 and Maryland HBR 9666Publishes broad ADU cost ranges, not a fixed project price
UP CraftsmenDesign-build ADU series; some prefabricated production languageMontgomery County focus; site states service across MarylandDesign, engineering, permit walkthrough, construction and installationPublishes MHIC 0151386No turnkey ADU price found on reviewed pages
Karma Construction GroupSite-built design-buildPublic ADU page names Montgomery, Prince George’s, Howard and Frederick countiesDesign, engineering, permitting and construction under one contractPublishes MHIC 108917 and Maryland HBR 8756No Maryland ADU price found on reviewed pages
Clarksville Construction ServicesCustom site-built ADUs / in-law suitesCompany markets ADU construction across Maryland; Maryland HQ and Eastern Shore divisionCustom design/build; exact ADU permit scope should be confirmed in proposalPublishes MHIC 78947No ADU-specific public price found on reviewed pages
Capital ADUTurnkey ADU specialistMaryland, DC and Northern Virginia; dedicated Bethesda and Silver Spring pagesDesign, architectural/structural/MEP plan set, permit management and constructionSite states licensed in Maryland; license number did not surface on the reviewed public pagesNo Maryland turnkey price found on reviewed pages
PurBiltModular builderMaryland-wide modular homes, ADUs and additionsFloor plans, permits, factory build, delivery and setPublishes MHIC 73624 and MHBR 8942Publishes general modular-home ranges; not ADU-specific
DC StructuresPrefab / pre-cut kit supplierShips building kits across MarylandIn-house design and permitting support; a local build/site scope is still requiredKit supplier rather than a Maryland turnkey contractor in this comparisonPublishes kit starting prices and warns turnkey cost can be multiples of kit price
Mod PodzSmall-space / mobile and custom buildsBowie-based; company states it builds ADUs and is licensed in MarylandCompany states it can assist with permits and regulationsStates Maryland builder/MHIC licensing, but number did not surface on reviewed pagesPublishes starting prices for some mobile models and a custom-build $/sq-ft range

Prefab in Maryland: the approval distinction that matters before you shop

Maryland’s Department of Labor distinguishes a true industrialized/modular building from a manufactured/mobile home. A Maryland modular home is substantially built off site, intended for a permanent foundation, and regulated through the state industrialized-building program. The state reviews the factory-built unit, while the local building department still reviews the permit, site, foundation and other site work.

Maryland also maintains current lists of approved industrialized/modular manufacturers and model/project approvals. A brand name on a sales website may not be the same name as the actual factory manufacturer or model identifier shown in state records.

Before paying a prefab deposit: ask the seller for the actual manufacturer name, plant/manufacturer identifier, exact model number, the Maryland approval/certification path for that model, and who is responsible for the Maryland green certification label/insignia. Then separately confirm who is handling the local foundation, grading, utilities, stormwater, septic/well, crane access and building permit.

We reviewed Maryland’s 2026 public model-status and approved-manufacturer pages. We did not use the absence of a retail brand name from those lists as proof that a product is unapproved, because a retailer may use a separate approved factory manufacturer. The correct verification is model-by-model.

What the companies actually publish about price

Published prices are difficult to compare because they describe different scopes. A kit price, factory module price and turnkey ADU contract are not equivalent.

ProviderCompany-published price informationImportant limitation
Makara ADUIts Maryland cost article gives a broad range of roughly $60,000–$225,000 for ADUs, with larger/high-finish projects potentially above $300,000.The same company explains that site development and soft costs can be additional; this is not a quote for a specific Maryland lot.
PurBiltPublishes a general Maryland modular-home range of about $150,000–$400,000 fully installed and a factory-module range around $80–$160/sq ft.These are general modular-home figures, not a published Maryland ADU price schedule.
DC StructuresIts Sitka ADU kit starts around $21,908; its Maryland kit page says complete turnkey cost can be 2–5× the initial kit price.The starting figure is a kit price, not a completed habitable Maryland ADU.
Mod PodzPublishes mobile-model starting prices around $89,000 and $135,000; FAQ says custom builds are generally around $200–$265/sq ft.Confirm whether the quoted product is a permanent code-compliant ADU, a mobile unit, or another classification and what site work is excluded.
UP Craftsmen / Karma / Clarksville / Capital ADUNo comparable Maryland turnkey ADU price was found on the public pages reviewed.Request a written scope-based proposal rather than comparing a private quote with another company’s marketing range.

Company-by-company notes

Makara ADU — ADU-focused design-build with Maryland project examples

Makara is based in Gaithersburg and publishes a large library of compact plans from roughly 300 square feet through 1,100 square feet, plus custom design. Its site shows Maryland examples in Bethesda, Germantown, Burtonsville, Silver Spring and Annapolis, and states that it handles feasibility, plans, permitting and construction.

Best reason to interview: the public project gallery provides Maryland-specific examples rather than only concept renderings. Ask: which civil, utility, stormwater, septic/well and landscape-restoration items are included in the proposal, and whether the published cost ranges match your county/site conditions.

Company website →

UP Craftsmen — Montgomery County-focused design/build process

UP Craftsmen is headquartered in Silver Spring and markets an end-to-end process covering design, engineering, permit walkthrough and construction. Its site emphasizes Montgomery County familiarity, offers a feasibility-study entry point, and publishes MHIC 0151386.

Best reason to interview: strong local focus for Montgomery County. Ask: whether your proposed residential ADU is site-built or uses a prefabricated product line, who is the manufacturer if factory-built components are used, and whether final county licensing/inspection tasks are included.

Company website →

Karma Construction Group — multi-county full-service design/build

Karma’s Maryland ADU page names Montgomery, Prince George’s, Howard and Frederick counties and describes design, engineering, permitting and construction under one contract. Its licensing page publishes Maryland MHIC 108917 and HBR 8756.

Best reason to interview: multi-county design-build scope with public license identifiers. Ask: for completed Maryland ADU references in your specific county and a line-item explanation of site work, utilities, fees and allowance items.

Maryland ADU page →

Clarksville Construction Services — established Maryland custom builder

Clarksville Construction markets custom ADUs and in-law suites across Maryland and operates from Hanover with an Eastern Shore division. The company publishes MHIC 78947. Its public positioning is broader custom construction rather than a standardized prefab catalog.

Best reason to interview: custom/site-built option for homeowners who do not want to force a lot into a stock prefab plan. Ask: who prepares the ADU drawings/engineering, what county permitting experience the assigned team has, and whether the contract is fixed-price, allowance-based or cost-plus.

Maryland ADU page →

Capital ADU — DMV turnkey specialist with Maryland service pages

Capital ADU states that it designs, permits and builds turnkey ADUs across Maryland, DC and Northern Virginia, with dedicated Bethesda and Silver Spring pages. Its planning service describes architectural, structural and MEP permit-ready drawings plus permit management.

Best reason to interview: ADU-specific planning and permit workflow. Verify before contracting: its site says it is licensed in Maryland, but a Maryland license number did not surface on the public pages we reviewed. Ask for the exact legal contracting entity, current Maryland license number and certificate of insurance before signing.

Company website →

PurBilt — Maryland modular builder handling factory build, delivery and set

PurBilt is based in Arnold and markets modular homes, ADUs and additions across Maryland. It states that its modular process can include floor plans, permits, factory construction, delivery and set, and publishes MHIC 73624 and MHBR 8942.

Best reason to interview: a Maryland-based modular path rather than a kit-only purchase. Ask: which factory/manufacturer and specific Maryland-approved model would be used for your ADU, whether crane/set, foundation, utility connections and local inspections are in the price, and which costs remain provisional until site evaluation.

ADU / additions page →

DC Structures — prefab kit route, not the same as turnkey modular

DC Structures ships pre-engineered building kits across Maryland and markets the Sitka as an ADU kit in multiple sizes from about 405 to 864 square feet. Its Maryland page explicitly warns that the final turnkey cost can be several times the initial kit price.

Best reason to interview: useful for homeowners deliberately shopping for a kit and willing to coordinate local construction. Ask: exactly what materials/design services are included, who becomes the Maryland builder of record, how the plans are adapted for the local jurisdiction, and who owns responsibility for MEP, foundation, labor, utilities and inspections.

Maryland ADU kit page →

Mod Podz — small-space/mobile pricing is visible, but classification must be verified

Mod Podz is based in Bowie and states that it designs and builds homes, ADUs and small intentional spaces and is licensed in Maryland. Its public model page includes mobile products with starting prices, and its FAQ publishes a general custom-build range.

Best reason to interview: one of the few Maryland-facing small-space companies publishing starting prices. Critical question: is the exact product you are pricing a Maryland industrialized/modular dwelling intended for a permanent foundation, a manufactured/mobile unit, or another type of structure? Ask for the exact model approval/certification path before paying a deposit for use as an ADU.

Company website →

What about Maryland MicroNest?

Maryland MicroNest markets “The Chessie,” a one-bedroom steel-framed modular/tiny home for the DMV and says delivery can occur in as little as 60 days. We found enough public information to flag it as a product worth investigating, but not enough on the reviewed page to independently connect the branded product to a specific Maryland approved manufacturer/model record or to compare an installed Maryland price.

That does not mean the product is unapproved. It means a homeowner should ask for the manufacturer name, exact model identifier, Maryland approval/insignia path, local installer/builder, foundation scope and total installed price before treating the marketing page as a permit-ready solution.

Maryland MicroNest →

11-question Maryland ADU builder scorecard

  1. What exact legal entity will sign my construction contract? Get the entity name and Maryland license/registration numbers that apply to your project.
  2. Have you completed an ADU in my county or municipality? Ask for a comparable permitted project, not only a rendering.
  3. Who confirms zoning feasibility before I pay for full design? Cross-check with our County Rules Tracker.
  4. How are you calculating my maximum ADU size? Maryland measurement methods differ; use our 75% Size Calculator & Measurement Guide.
  5. Who owns the permit process? Identify zoning, building, electrical, plumbing, mechanical, rental/license and historic-review responsibilities.
  6. What is excluded from the price? Ask specifically about survey, civil engineering, geotechnical work, foundation, grading, stormwater, retaining walls, utility trenching, septic/well, impact/connection fees, crane, landscaping and restoration.
  7. If modular/prefab, who is the actual manufacturer and what is the Maryland model approval path? Request the model identifier—not only the retail brand.
  8. What assumptions can trigger a change order? Get the allowance and unknown-condition language in writing.
  9. When does your schedule clock start? “120 days” may mean after permit, after factory release, or after site readiness.
  10. Who is responsible for final inspections and certificate/license closeout? A finished structure is not the same as a legally occupiable ADU.
  11. Can I see insurance, warranty and payment schedule before signing? Avoid front-loading payments without clear milestones and deliverables.

Before paying a builder or prefab deposit

  1. Confirm the county rule set first. Maryland is still in a 2026 implementation transition.
  2. Run size and site feasibility before choosing a model. A beautiful 800-sq-ft plan is irrelevant if the local rule or lot supports less.
  3. Check septic/well early. Use our Maryland ADU Septic & Well Readiness Checker if the property is not clearly on public utilities.
  4. Verify the contractor’s current Maryland credentials. Do not rely only on a logo or “licensed” badge.
  5. For modular projects, verify the manufacturer/model approval path. Maryland maintains approved-manufacturer and current model/project-status records.
  6. Compare full project scopes, not headline prices. A $22,000 kit and a $200,000 design-build contract are different products.
  7. Do not buy a unit first and solve permitting later. Local site constraints can make transport, crane placement, foundation, utilities or the ADU itself infeasible.

Our editorial methodology

We included companies because we found current public evidence that they market ADU, modular or relevant prefab services to Maryland. We prioritize original company pages for service scope and pricing claims, and Maryland government sources for modular-building rules. We do not infer quality from advertising, awards, testimonials or SEO rankings.

This is a research directory, not a recommendation list. If a company wants a factual correction, additional licensing detail, or clarification of what its published price includes, it can send supporting documentation to gijo.j@marylandaduguide.com. Paid relationships, if ever introduced, should be disclosed separately and must not determine editorial inclusion or ranking.

Primary and company sources used

Start with the Maryland ADU Guide 2026, verify your local status in the County Rules Tracker, then use the 75% Size Calculator and Septic & Well Readiness Checker before comparing builder proposals.