Knowing how a mobile home is constructed can help you remodel or transform your home. This is especially true if you need to replace the floor or move walls in your motorhome. If you know the construction methods and the construction process, you can plan your project better and save money.
Basics of prefab construction
Both the single and twin versions (essentially just two single models) sit on a steel chassis.
Steel beams with a slight curvature are welded together and form the curved chassis.
This is done to balance or distribute the weight of the house. These curves are barely noticeable, but they are vital to a solid man-made home that can withstand the forces of vibration and 55-mph transportation.
The arc or curvature of the steel frame helps the house absorb shock and distribute weight more efficiently.
The best frames are made from American steel. Some builders use cheaper Chinese steel; Try to stay away from these if you have another option.
The "left" and "right" beams have stabilizers at the ends. The legs have tapered edges and may or may not reach the very edge of the house.
Cheap prefab homes don't have stabilizers that stick out over the edge of the house.
Cantilevers that reach the edge are better because they better support the weight of the walls and ceiling. If the legs aren't strong enough or don't reach far enough, the fence and roof of the house can sag.
Aside from the structural integrity of the frame and roof, a prefab home is constructed in much the same way as a site-built home.
Once the chassis is built to specification, the contractor uses jigs or formwork to construct 2x6 or sometimes 2x8 floor joists for higher end homes.
Palm Harbor Homes uses a computer aided design program to design the floor joists for each model.
Heating and cooling vents, pipes and cables are routed through the floor joists. On some models, the plumbing and electrical systems pass through the ceiling joists.
Next, the sub-floor and the floor covering are laid.
How prefabricated walls are built
The walls are made of wooden boards, so-called stollen. Studs are vertical panels typically spaced 2" x 4" every 16" in prefab homes. This is the meaning of the term 16 inch OC, or "in the middle" in construction jargon. Prefabricated houses of higher quality have 2x6 studs, cheaper houses have 2x3 studs. State laws and wind zones determine how your mobile home is built.
Interior walls, sometimes called partitions because they separate spaces and support no mass, can be 2x2 and spaced 24 inches apart.
The posts are held together by horizontal plates called base and top plates. Home Tips shows a partial illustration of a helpful wall:
The walls around the windows and doors are constructed differently to spread the weight on each side of the raw opening. Structural headers are used above windows and doors to reinforce the area. Usually either a trimmer or a king stud is used (sometimes both, but less often).
How walls are connected with beams and trusses
The baseboards of the interior walls are nailed to the floor joists. The floor and ceiling enclose the walls, forming a structurally stable wall.
The exterior walls of a prefab home are attached to the floor joists using 26 gauge metal strapping and nails as shown below. These are also called hurricane belts.
The boundary walls are attached to the ceiling joists with metal strips and nails as shown below.
If your prefab has roof joists that rest completely on the roof slab, this usually indicates a load-bearing wall.
In fact, a double width consists of just two single widths. Each double-width piece has its own integrity and strength, but together they create a stronger home.
In the image below you can see half the double width with the interior and exterior walls installed. Please note that there is no roof yet. The roof will be built separately from the rest of the house and will be installed after all interior work is completed.
Double width roof
Wide dual purpose roof trusses
Once assembled to the walls, the roof forms a strong web of structural integrity.
Exterior construction of a new mobile home
Some RV builders do things a little differently. Some brands install the roof first and then add the siding, others add the siding before the roof.
Jacobsen Homes does the latter. Jacobsen Homes posted a video on YouTube showing the construction process for their prefab home. All the videos I've seen seem to accuse other brands of cutting corners or using cheaper materials more often, which I like.
The outer paneling is made of plywood or OSB panels. There is a petrochemical called Thermo-Ply. It's cheaper and doesn't seem to stand up to the factors either.
Video tours and construction videos
Below we have added construction videos from some of the best prefab house manufacturers. This should give you an easy way to see how each company is different. However, note that some of the brands below are owned by the same company, so there really isn't much of a difference.
Also keep in mind that in these videos these brands flaunt their best models and therefore their best structures. Most models offered by manufacturers do not have listed materials.
How homes manufactured by Clayton Homes are built
How homes manufactured by Jacobsen Homes are built
How prefab homes are built in Palm Harbor
How houses manufactured by Champion Homes are built
The TV show How It's Made is about factory made homes
How houses manufactured by Schult Homes are built
How Golden West Homes mobile homes are built
10 smart upgrades when buying a new mobile home
Get a better insight into prefabricated houses
If you want to visualize the double width building process, this image should help you. I found itFrey's sales site for prefabricated houses and mobile homes.
1. 2x10 #2 SPF floor joists or better at 16” spacing.
2. Perimeter heating with registers and wall connections.
3. Shaw Acclaim 16 oz Casual Textured Area Rug with 5 pounds of recycled padding.
4. 2x6 SPF cleats or better placed on 16" centers.
5. 2x10 headers over all windows and doors.
6. Outer panel made of 7/16″ Oriented Strand Board.
7. Owens Corning R-19 fiberglass wall insulation.
8. R-33 cellulose roof insulation.
9. Optional 7/12 roof pitch with 50 or 70 pound snow loads.
10. 2x6 stops.
11. 7/16″ OSB Outer Roof Panel.
12. Construction of tiles.
13. Fully finished drywall throughout the house.
14. Double glazed single wing single tilt vinyl windows.
15. 36 x 80 6 panel vinyl coated steel insulation doors, weather resistant front and back.
Find out more about the 3 quality and price levels here.
Conclusion: How prefabricated houses are built
For those looking to renovate an older home, knowing how mobile homes are built is a good idea.Movil HouseOr buy a new RV.
Over the years, manufacturers of prefab houses have refined their building process to a high science and the quality of the houses has improved dramatically.
Building a house in a factory is a safer and cheaper way to build a house.
Advanced computer-aided design, dedicated machinery, and strict inventory controls allow brands to build prefab homes at half the cost per square foot of a site-built home.
Building a home in a temperature controlled factory results in higher quality products with a highly skilled workforce who know they will have a job tomorrow. People working regular shifts are the best general method for home construction.
As always, thanks for reading.Life in the mobile home!
Updated April 13, 2019(MMHL does not endorse or recommend any manufacturer over another. Each manufacturer has its own strengths and weaknesses.)
What are the advantages and disadvantages of prefab homes? ›
- Benefit #1: Affordability.
- Benefit #2: Energy Efficiency.
- Benefit #3: Relatively Fast Construction Process and No Waste.
- Drawback #1: Transportation and Assembly Factors.
- Drawback #2: You Have to Buy the Land.
- Drawback #3: Utility Hook Up and Other Hidden Costs.
What are prefab houses made of? The construction of a prefab home relies on using many of the same materials associated with a traditional home. The most common being wood, steel and concrete.Why are prefab homes sustainable? ›
As modular homes are built in factories according to specific measurements, there's no need for excess material, which reduces building waste significantly. The prefabrication of trusses, frames and other parts can reduce waste by 52%.Are prefab homes good for the environment? ›
Modular homes reduce a lot of the environmental impact associated with traditional home construction. They surpass conventional homes in energy efficiency, waste management, emission production, material transportation and are adaptable to their environment.What are four advantages of prefabrication? ›
Prefabrication technology has several advantages, such as energy efficiency revision, minimal waste and inspection, efficient construction, work speed, protection, sustainability and quality. As self-supporting ready-made components are used, the need for formwork, shuttering and scaffolding is substantially lowered.What are the challenges in prefabricated buildings? ›
Prefabrication structures is less water resistant hence there is leakage problem in joints. Leakages can be reduced by welding or silicon solutions, water resistant.What are the benefits of prefabricated homes? ›
One of the benefits of prefab homes is that they tend to be highly energy efficient. Their tight seams and state-of-the-art windows keep heat in and reduce your energy bills in the process. As a bonus, modular homes' tight construction gives them a reputation for being able to withstand natural disasters.Why prefabricated construction is better? ›
The Pros of Prefab
This is a controlled, safe environment which allows owners to streamline the construction process and cut down on waste. This makes prefab cost effective. In many cases, prefab also reduces environmental impact. It can lessen air, water, and noise pollution caused by a construction project.
Prefab is a general term used for a prefabricated building or building component that is manufactured in a factory prior to its final assembly at the construction site, whereas modular refers to something built or organized in self-contained units—like building blocks.How long do prefabricated buildings last? ›
However, they are still designed to last around 25–30 years—certainly not an eternity, but definitely long enough to serve their intended purpose. Leasing or purchasing a used modular building will mean its lifespan is slightly shortened, having already been owned for a few years.
What is one of the drawback of prefab? ›
One of the widely known demerits of a prefab building is that it does not offer the same level of quality as traditional.What are the disadvantages of prefabrication in construction? ›
- Road transport maximum widths.
- The need for police escorts.
- Height restrictions under bridges.
- Daytime traffic restrictions in city centres.
- Maximum load capacities of site craneage and temporary gantries.
Prefabricated concrete homes
Concrete is one of the best building materials: it is robust, sustainable, functional and resistant to adverse weather conditions. In addition, concrete offers a modern design, creating houses with straight and simple lines, flat roofs and large windows.
Hurricane-force winds are well endured by manufactured housing. Modern Custom Modular homes comply with safety and construction standards and are structurally sound, safe, and weathertight. Manufacturers are also required to use products that protect the home from mold, corrosion, insect infestations, and decay.What is the cheapest home to build? ›
Ranch homes are the most popular home style in the U.S. They're another rectangular-shaped house, though they come in “T” or “L” shapes, too. A home with a simple and concise layout is the cheapest type of house to build. Ranch homes are typically single-story structures with attached garages.Why do we need prefabrication? ›
Prefabrication avoids the need to transport so many skilled workers to the construction site, and other restricting conditions such as a lack of power, lack of water, exposure to harsh weather or a hazardous environment are avoided.How much does prefabrication save? ›
 Prefabrication can speed construction by as much as 50% and can cut construction costs by 20%. Project owners may also be able to reduce materials costs by 5% to 10%.What is the purpose of prefabrication? ›
Prefabrication, therefore, helps companies speed up timelines, make the most of the labor they have on-site, increase productivity and compete in the marketplace. Cost-effectiveness: Moving partial assemblies from a factory often costs less than moving pre-production resources to each site.What is the reason to say prefabrication is modern construction? ›
Prefabrication is considered as modular construction - a highly sustainable and energy-efficient construction practice. It also includes a lot less waste than traditional construction methods. Since all construction elements are prefabricated, there's no need for any extra materials, which means less waste.What are the negatives of modular architecture? ›
The cons of modular construction
Because modular construction components are prefabricated away from the job site, you have to consider transportation costs and the risk of damage during transport. It only takes one mishap during transportation to cause a significant setback.
What are the stages of construction in prefabricated structures? ›
- The first stage - engineering and design work. ...
- The second stage is the preparatory work. ...
- The third stage - installation work. ...
- The fourth stage is the acceptance by the customer of the object.
- Precision Assembly. The repeatable nature of in-factory construction allows builders to continuously improve equipment and processes that cannot be reproduced onsite. ...
- Weather Protection. ...
- Reduced Waste. ...
- Quality Control. ...
- Reduced Site Disruption.
Lower cost: Using conventional construction methods can cost $150 to $250 per square foot if you're building a standard, non-luxury home. Modular construction can cost 10% to 20% less thanks to assembly line efficiency.What does prefabricated mean in architecture? ›
A prefabricated building, informally a prefab, is a building that is manufactured and constructed using prefabrication. It consists of factory-made components or units that are transported and assembled on-site to form the complete building.What is the future of prefabrication in construction? ›
The future of construction is looking bright, and prefabrication is playing a major role in this transformation. With the demand for faster, more efficient and sustainable building methods on the rise, prefab construction is quickly becoming the go-to solution for many architects, builders, and developers.Why is prefabrication cheaper? ›
Most prefab homes are more affordable and sustainable than standard-built homes, since they are manufactured and built using a set number of pre-made pieces to prevent material waste. These homes are also usually built to be more energy efficient and more weather resistant as well.What is the first stage of prefabricated structure construction? ›
The main stages of prefabricated buildings erection are the preparatory period, the construction of the substructure, the construction of the superstructure, the construction of external supply lines and site improvements.Is a double wide the same as a manufactured home? ›
A double wide home is another type of manufactured home and isn't built on site. Because of this, a lot of customization options are available. These homes can be moved to anywhere you'd like, consisting of two sections, joined together to create a larger home.What is a prefabricated home? ›
Prefabricated, or “prefab,” homes are manufactured piece by piece in an off-site factory, transported to the home site and assembled on the homeowner's property. For many, prefab homes are a fast and affordable way to build sustainable housing.Is modular construction the same as prefabrication? ›
Prefab is any construction process that does not take place on-site, while modular construction specifically consists of the building of repeated sections called modules being built in the factory and then assembled on site.
How long does it take to build a prefab? ›
If you want to construct a modular home, you can expect the entire process to take around 16-31 weeks. This range of time is based on numerous factors, which include: Whether you use a template home plan or a designed custom home. Timeline to apply for and obtain the necessary building permits.When did prefabricated building begin? ›
Prefabricated homes were produced during the Gold Rush in the United States during the 19th century to enable California prospectors to quickly construct homes. Also known as kit houses, pre-cut houses, ready-cut houses, mail order homes, or catalog homes, they remained popular into the first half of the 20th century.How long do cinder block buildings last? ›
Block doesn't rot, warp or grow mold, and it stands up remarkably well to even the most extreme weather. Even with a lifespan of up to 100 years, you can be sure the building's structural integrity isn't compromised over the years like it can be with wood.Is prefab more sustainable? ›
Prefabricated building materials also reduce energy consumption during construction. According to a report published by design, engineering and planning firm Arup, up to 67% less energy is involved in the construction of a building that uses modular construction. Multiple factors contribute to this reduction.Is a prefab an asset? ›
A prefab is an asset type that allows you to store a GameObject complete with components and properties. This allows us to share pre-configured hierarchies of objects between scenes.What is the difference between prefabricated construction and on site construction? ›
Traditional construction (aka “stick-built” buildings) uses a foundation that is built on-site using holes in the ground, concrete, and wooden piers. On the other hand. Prefabricated construction uses pre-constructed parts that are lifted by a crane onto a permanent foundation.What is the disadvantage of prefabricated concrete? ›
- Higher Upfront Costs. ...
- Transportation Can Be an Issue. ...
- You Have to Take Care When Handling Precast Concrete. ...
- Precast Concrete Can Be Hard to Modify Once Built. ...
- Improper Installation Could Cause Issues.
Therefore, the main difference between prefabricated and precast structures is that one is industrially made while the other can be produced in specific locations and does not require control, such as laboratory tests.What is the process of prefabrication? ›
Prefabrication refers to the process of building and assembling a structure at a manufacturing site and transporting it to a remote site where it's then used. This is in stark contrast to traditional manufacturing processes in which basic materials — though not necessarily raw materials — are transported to the site.Is it cheaper to build or buy prefab? ›
Are prefab homes more affordable than other types of housing? The general rule of thumb is that prefab construction is cheaper than stick-built homes by an average of 10 to 25 percent.
What type of building is prefabricated? ›
A prefabricated (prefab) building, by definition, is where an entire building or an assembly of its components is manufactured at an offsite facility and assembled onsite from self-sustained volumetric modules or separate panels.What is prefabricated framing? ›
Prefabricated framing is an innovative building method that streamlines construction and increases safety and efficiency. Prefabricated building components, such as frames and roof trusses, are made in a factory and then delivered to the construction site where they are assembled.Are prefab homes insulated well? ›
Are manufactured homes insulated well? They are! Manufactured homes are required to be insulated, and depending on the location of the manufactured home within the United States, they will be held to different standards of insulation.Are prefab homes a bad idea? ›
The dangers of modular homes are minimal. As long as the assembly of the modular home complies with local building codes, modular homes are as safe as a traditionally built home.What time of year is cheapest to build a house? ›
While spring is an ideal time to start building a home, the fall and winter months are usually when building materials and construction costs are lowest because there is less demand.What states are the cheapest to build a house in? ›
- Mississippi. Mississippi ranks at the lowest cost of living in the entirety of the United States. ...
- West Virginia. ...
- Alabama. ...
- Oklahoma. ...
- Kansas. ...
- Iowa. ...
- Ohio. ...
Overall, it's cheaper to build a home than to buy one in California, with 13 out of the 20 counties saving you money if you decide to build your house from scratch. Budget-wise, building is more favorable in Southern California whereas Central California caters best to those interested in buying.What is the life expectancy of a prefabricated building? ›
With proper care, temporary modular buildings have a service life of at least 25 to 30 years, after which the components are typically repurposed or recycled.What building material has the longest lifespan? ›
The longest-lasting building materials are wood, brick, stone, concrete, steel, and iron.What are the advantages of prefabricated walls? ›
- Safer Work Sites. Framing a home in the traditional way can be dangerous, especially as you start work on top of the first floor deck. ...
- Improved Build Quality. ...
- Minimized Labor Requirements. ...
- Faster Installation. ...
- A Value-Engineered Building Solution.
Are prefab homes earthquake safe? ›
Modular homes can be found in earthquake and seismic zones. Each house design is individually engineered to meet local seismic code requirements and to adapt to the natural terrain, utilizing one among the many foundation options available. The biggest misconception is that modular homes are flimsy and fall apart easy.