How Much Does a Modular House Cost? Choosing the Right Size and Budgeting

How Much Should You Budget For Each Modular House Size?

Today, modular houses come in a wide range of sizes, from compact getaway homes to full family residences - and each size comes with its own functions and budget.

40-50 sqm Modular Houses

Homes in this range are ideal for those looking for a getaway house, garden house, holiday home, or a private retreat for weekends. Examples include the Standard Type and Loft Type from our Unwind Series, with total floor areas of 43.5 and 47 square meters respectively, starting from around 830,000 - 1,190,000 baht. Despite their compact size, they still fully support essential everyday needs, with a large terrace that extends the living space outdoors - perfect for relaxing and living closer to nature.

Around 80 sqm Modular Houses

Once floor area reaches around 80 square meters, a home starts to comfortably support day-to-day living. For example, our 1 Bed 2 Bath Type has a total floor area of 82 square meters, starting from around 1.66 million baht. What makes this size stand out is that it includes all the essentials for real living - a separate bedroom, 2 bathrooms, a kitchen area, and a laundry area - making it ideal for couples, retirees, or anyone wanting a genuinely livable second home for the long term.

120+ sqm Modular Houses

For those wanting more space, homes in this range start to feel much closer to a conventional single-family house.

For example, our 2 Bed 2 Bath Type has a total floor area of 123 square meters, starting from around 2.66 million baht. With more room to work with, it comfortably accommodates a small family - with private areas, shared living space, and outdoor relaxation space - ideal for long-term living or as a family getaway home.

Size and Function Comparison for Under-a-Million Budgets

For a clearer picture, here's a quick comparison of what you get across different modular house price ranges.

What Factors Affect the Price of a Modular House?

Even two homes of similar size can vary in price for several reasons:

1. Floor Area

Floor area is the single biggest factor affecting price - the larger the space, the more materials and construction work required.

That said, choosing a home larger than you actually need can push your budget up unnecessarily. It's always worth starting by analyzing your real usage needs first - how many rooms you need, and how many people will be living there.

2. Interior Functions

Homes with the same floor area can vary in price depending on the number of bathrooms, bedrooms, or special-use spaces.

For example, a home with 2 bathrooms, a full kitchen, or a dedicated laundry area will naturally cost more than one focused on the basics.

3. Materials and Finishes

The materials you choose affect appearance, lifespan, and budget all at once. Beyond aesthetics, it's worth considering suitability for Thailand's climate, resistance to humidity and sunlight, and ease of long-term maintenance.

4. Structural System

The structural system is at the heart of every modular home, since it directly affects strength, safety, and long-term lifespan.

Every brand may have different material standards. For example, Clay & Stone uses TIS-standard steel structures that are thicker than typical specs, along with a premium anti-rust coating system to help protect the structure from Thailand's hot, humid climate. So beyond comparing prices, it's worth considering structural quality, materials, and manufacturing standards together, since these directly affect durability and long-term maintenance costs.

5. Transportation and Installation

Modular houses are manufactured at the factory and installed on site, so distance and site conditions can add extra transportation and installation costs in certain cases - especially for hard-to-access locations or sites requiring special equipment for delivery and setup.

Additional Costs to Plan For

Beyond the cost of the house itself, there are other expenses worth planning for from the start to avoid budget overruns later.

Site Preparation

If your land hasn't been leveled or filled, there may be additional costs for preparing the site before installation.

Foundation Work

Even though modular homes are lighter than conventional construction, they still need a foundation suited to the soil conditions of each site.

Many builders today are shifting to precast foundation systems to reduce construction time and improve quality control. At Clay & Stone, we use a factory-made precast foundation system that reduces on-site concrete pouring, keeps the construction site tidier, ensures better quality control, and allows for faster installation than traditional foundation methods.

Electrical and Plumbing Systems

This includes meter installation, water supply and drainage pipes, septic tanks, and utility connections - all of which should be planned from the start to avoid unexpected costs later.

For many homeowners, coordinating multiple contractors can be time-consuming and detail-heavy, which is why many prefer a provider who can manage the building systems alongside the house construction itself, keeping the process smooth and easier to control for quality.

Landscaping and Outdoor Areas

This includes walkways, gardens, fencing, or outdoor seating areas - a budget item many people forget to account for early on. In reality, outdoor space affects both the atmosphere and functionality of a home just as much as the house itself. Planning your landscaping alongside your home design from the start creates a more cohesive project, both aesthetically and functionally, while keeping the budget under control.

Furniture and Appliances

Even though the house itself is move-in ready, actually settling in still requires a budget for interior decor and appliances based on your needs.

For those wanting extra convenience, many providers today offer interior design and built-in furniture services alongside the home build, which helps keep the interior design cohesive with the overall architecture and makes the space more efficient to use. Clay & Stone has a team that can handle and coordinate this for you as well.

How Much Extra Budget Should You Set Aside?

As a general rule, set aside an additional 20-30% of the cost of the house itself for site preparation, foundation work, utility systems, and related outdoor work.

Planning your budget thoroughly from the start reduces the risk of unexpected costs and helps your project move forward smoothly.

The Right House Is the One That Fits Your Needs

Choosing a modular house isn't about picking the biggest or most feature-packed option - it should start with understanding your lifestyle, budget, and real needs. Whether it's a compact getaway home, a second home, or a family residence, choosing the right size from the start ensures you get space that's genuinely worth the investment and suited for long-term living.

For those who love a warm, simple atmosphere close to nature - with extended eaves, a functional terrace, and interior functions that suit everyday life - that's exactly the approach Clay & Stone takes in designing our prefab homes.

We design prefab homes that aren't just beautiful in photos, but genuinely comfortable, strong, and delivered exactly as designed. Our professional team of architects and engineers oversees the entire design, construction, and installation process, backed by direct after-sales support from the Clay & Stone team, so homeowners feel supported well beyond the handover. Because a good home doesn't need to be the biggest or the most expensive - it should be the one that fits your life, your budget, and how you feel every day. Contact Clay & Stone to talk with our team and find the prefab house design that's right for you.

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