Modular Home Cost Calculator

A modular (prefab) home typically costs $100 to $250 per square foot all-in (turnkey), so a 1,800 sq ft modular home commonly runs roughly $180,000 to $450,000 including the home, delivery, set, foundation, and finishing — though the base modules alone (before site work and foundation) can be considerably less. The cost depends on the home's size, the module class (single-section is cheapest, multi-section standard, custom modular premium), the finish level, the site conditions, and the substantial 'site costs' beyond the factory price: foundation, utility connections, transport and crane set, design and permits, and any garage or porch/deck. The manufacturer's base module price is just part of the total — land, foundation, utilities, delivery/set, and finishing add significantly to reach the turnkey figure. A ~$50,000 minimum applies. Modular is often comparable to or somewhat less than an equivalent stick-built home, with savings from efficient factory construction and faster build times. Use the calculator above to build a realistic total.

They're different construction methods that are often confused. A stick-built (site-built) home is constructed entirely on-site, piece by piece — the traditional method. A modular home is built in sections ('modules') in a factory, then transported and assembled on a permanent foundation; crucially, modular homes are built to the same state and local building codes as site-built homes, so once installed they're essentially indistinguishable from stick-built homes for financing, appraisal, and resale, and are considered real property. A manufactured home (formerly 'mobile home') is also factory-built but to the federal HUD code rather than local codes, sits on a permanent steel chassis, and is often on a non-permanent foundation — a distinct category with different financing, sometimes treated as personal property. In short: modular = factory-built to local codes on a permanent foundation, treated like a regular house; manufactured = factory-built to HUD code on a chassis; stick-built = built on-site. Modular bridges the two — factory efficiency with the code compliance and permanence of site-built. This calculator covers modular/prefab homes.

Modular homes are often somewhat cheaper than an equivalent stick-built home, but not always dramatically so. Where modular saves: factory construction is efficient — building indoors avoids weather delays, allows bulk purchasing and assembly-line efficiency, cuts material waste, and streamlines labor, lowering the cost of the home structure itself; and the much faster build (modules are built while site work happens in parallel) saves on construction-loan interest and gets you in sooner. Where the savings shrink: the 'site costs' — land, foundation, utilities, delivery, crane set, permits, and finishing — are largely the same as for stick-built and don't benefit from factory efficiency, so the total turnkey gap narrows once they're added; transport and crane costs are unique to modular; and high-end custom modular can cost as much as custom stick-built. So modular typically offers modest structure savings (often 10–20%) plus significant time savings and pricing predictability — but not always a huge discount once everything's included. The faster timeline and quality control are often as valuable as the cost savings.

The most common budgeting mistake is focusing only on the manufacturer's base module price and underestimating the 'site costs' needed to make it a finished, livable home — these can add 30–50% or more on top of the modules. The major ones: land (buying the lot, not in construction estimates); site preparation (clearing, grading, and access for delivery trucks and a crane); the foundation (a permanent slab, crawl space, or basement — a significant cost, offered here as an add-on); delivery and set (transporting the modules and craning them onto the foundation — a modular add-on here); utility connections (water, sewer or septic, electric, and gas, especially costly in rural areas — an add-on here); 'button-up'/finishing (sealing seams, finishing the roof line, connecting systems, interior touch-ups); design and permits (architectural/engineering and permit fees — an add-on); plus extras like a garage, porch/deck, driveway, and landscaping. The turnkey cost is the module price plus all of these, so always budget the full picture, not just the factory quote. This calculator includes the major site costs as add-ons so your total is realistic.

Speed is one of modular's biggest advantages, because the factory build and site work happen in parallel. The factory build of the modules usually takes about 1 to 3 months once the design is finalized and ordered, with the modules constructed indoors regardless of weather, while the site work — lot prep, foundation, and utilities — happens concurrently. Once the modules are done and the foundation is ready, delivery and setting them with a crane takes just a day or a few days. Then the on-site 'button-up' and finishing — joining modules, completing the roof, connecting systems, and final finishing — typically takes a few weeks to a couple of months. From order to move-in, a modular home often takes about 3 to 6 months total, versus 6 to 12+ months for a comparable stick-built home. That speed reduces construction-loan interest, gets you in sooner, and avoids the weather delays that plague site-built homes. The design/permitting phase beforehand and a popular manufacturer's queue can add lead time, so start early.

Yes — modern modular homes can be quite customizable, dispelling the cookie-cutter myth, though the degree depends on the manufacturer and the class. Most companies offer floor plans that can be modified, and many let you adjust layouts, exterior styles and finishes (siding, roofing, porches), interior finishes (cabinets, countertops, flooring, fixtures), and features (fireplaces, kitchen islands, bath configurations). Multi-section and especially custom modular homes (this calculator's custom-modular class) offer extensive flexibility — you can work with the manufacturer or a designer to create a custom home built modularly, rivaling custom stick-built looks. The constraints come from the method: modules must fit transport width/height limits for the road and be craneable, which influences room dimensions and how the home divides into modules, and very complex geometries are harder modularly. But within those practical limits there's substantial room to personalize — from tweaking a standard plan to a fully custom design. The module-class and finish-level options here reflect that range from economical to premium custom.

Yes on both — an important distinction from manufactured (mobile) homes. Value: because modular homes are built to the same local building codes, set on permanent foundations, and are essentially indistinguishable from stick-built homes, they're appraised and treated as real property and appreciate (or depreciate) based on the same market factors — location, condition, size, and local trends — rather than depreciating like a vehicle. A quality modular home in a good location holds its value well, unlike manufactured homes that can depreciate, especially on leased land or a non-permanent foundation. Financing: modular homes qualify for conventional mortgages (and FHA, VA, etc.) just like site-built homes — you typically use a construction loan during the build that converts to a standard mortgage. Manufactured homes, by contrast, may require different, sometimes costlier financing like chattel loans. Appraisers and lenders treat code-compliant modular homes on permanent foundations as conventional houses, so you get the financing access and value retention of a traditional home with factory-build efficiency.

Modular homes are placed on permanent foundations — a key feature separating them from mobile/manufactured homes on temporary supports — and the type depends on your site, climate, and preference, mirroring stick-built options. A slab (concrete poured on the ground) is the most economical and common in warm climates without freezing concerns; the home sits directly on it. A crawl space raises the home on short foundation walls with access to utilities and plumbing underneath and some moisture protection — common in many regions. A full basement adds a level below the home — the priciest option but it adds significant usable or storage space, and it's cost-effective in cold climates where foundations must extend below the frost line anyway. The foundation is a substantial separate cost (offered here as a +$20/sq ft add-on), must be built to support the modules and meet local codes (including proper depth for the climate), and is what the modules are craned onto and secured to. Slab is cheapest, basement priciest; your builder and local codes guide the choice.