The reason I am taking a look at modular homes today and noding the topic is because it looks like I am about to build one. Most of the old family farm will soon be sold to a new owner, including the old farmhouse in which I currently reside. I will get a few acres off the old farm to build a new house on, but will need a place to live, and need to build it fairly quickly. I have gotten most of the information for this node from the catalogs and web sites of several manufacturers of modular housing, as well as extended conversations with experienced builders of modular homes as I have discussed my plans.
My introduction to the concept of modular housing came to me as a child, when almost overnight a vacant lot in my somewhat eclectic suburban neighborhood sprung forth a house that had been cut in half lengthwise, moved to the site and reassembled. It wasn't a very good house, it was small and fairly old and undoubtedly purchased for next to nothing from a developer or government agency that needed the house out of the way to make room for an apartment complex, shopping mall or road. Though somewhat of a blight on the neighborhood, it provided inexpensive housing to a family that was hard-pressed financially. In a rapidly developing section of Baltimore County, it was not uncommon to see old houses torn down, burned down, or moved to make way for higher density development. As a kid, it was sad to see something as useful and valuable as a house deliberately destroyed, so in a way it was good to see that a house was "saved" from the bulldozers.
Modular Housing is much the same concept as that old house, except that a modular house built in a factory, is designed from the ground up to be transported to the building site as modules, then assembled on site. Modular Housing differs from another form of manufactured housing, the mobile home or double wide in that the house is constructed out of materials more similar to conventional construction than a trailer, though a double wide could be considered a type of modular house. This is in contrast to a stick built house, which is built almost entirely of individual components assembled on site. A modular house can be finished off and ready to live in within a couple of weeks of being delivered and set on its foundation, since the interior walls, plumbing, electrical, cabinets and so on are already in place. Once the house is set on its foundation with a crane, all that is needed to finish the house off is to erect the roof trusses and install the roof, put siding on the joined walls, connect plumbing, electrical and HVAC systems, do final trim, spackling, and flooring work, and install any custom features such as fireplaces, skylights, and so on.
History of Modular Housing
The modular housing industry of today is the result of the evolution of mass-production of components that
go into building a house. Before the 1960s, most houses were stick built, with individual pieces of lumber, shingles, nails, and assembled at the building site. Sears Roebuck sold complete houses as kits back in the 1920's, each piece precut and marked like a huge erector set, but the house was still essentially stick-built. However, by the 1950's it was becoming commonplace for large developers to build many identical or similar houses, and individual components such as roof trusses became mass-produced to save money and time, and because specialized equipment in a factory could produce a better product than could easily be built in the field.
The next step were panelized homes which entire walls were preassembled at a factory, transported by truck and assembled into complete houses. Inexpensive homes could be assembled quickly on-site. The next step was to assemble entire finished or semi-finished sections of houses into modules, which were then trucked to the site and assembled into complete homes. The first were inexpensive and small ranchers or double wides, but today modular homes can range from small ranchers and cottages to large multistory luxury homes over 5,000 square feet in size. Townhouses, hotels, and commercial buildings can also be built with modules as well. Bank branches and fast food establishments are well suited for modular construction due to their fairly small size and built-in standardization.
Comparison of Modular to Conventional Construction
Costs for modular housing can be cheaper than for conventional construction, due to the ability to use specialized equipment, labor, and the ability work in a controlled environment without worries about weather in a factory environment. Buying power of a large manufacturer can deliver a quality product cheaper than a custom builder can in many cases. The cost advantage can be offset due to the high cost transporting the modules from a distant factory to a building site. With a modular house, the best bang for the buck seems to be around 1,500-2000 square feet in a ranch house or Cape Cod configuration. This is about the maximum size that a house can be constructed a using only 2 modules. A module is limited to a maximum size of about 60 feet long and 16 feet wide, or about 950 square feet, though most modules are in the range of 12-14 foot in width. Longer and wider modules present more problems navigating roads and especially neighborhood streets. More modules mean more trucks, and the increased cost of transporting and assembling the house is reflected in the price. The other main factor working against the cost advantage of a Modular is the cost of adding custom features to the house that require modification to the basic floor plan, or use of materials such as brick, stone, or ceramic tile, which are difficult to transport preinstalled. Again, sticking with a standard design and materials will maximize the cost savings, but limit your choice of materials and finishes. The cost advantage of a modular over a stick built house of similar size and quality is about 5 to 10 percent when sticking to a more or less standard configuration. Indirect cost savings can be realized due to quicker and simplified on-site construction, since there is less opportunity for weather, vandalism, labor, and materials shortages to disrupt construction. YMMV, depending on where and when you build.
A house of modular construction should be at least equal in quality to a comparable stick built house. In general, you get what you pay for, cheap modular homes like cheap stick built homes have thin carpeting, poor insulation, leaky windows, and sparse framing. Quality depends on a lot of things, such as the grade of materials used, the skill of the workmen who build the house and so on. The most difficult challenge for a modular house is to build it so it survives the journey from the factory to the building site intact. In order to do this, the manufacturer builds the house with more and better fasteners, adhesives, etc, and builds to tighter tolerances than a stick builder can get away with. Once in place, a modular home owner should have fewer problems with nail pops, warpage, squeaky floors, etc. However, many premium materials, such as hardwood floors, ceramic tile, and stone are poorly suited for factory installation and transport in place. If you are satisfied with linoleum and carpet for flooring, this is not really a problem. Premium materials can be installed later, but in some cases will cost more than having it installed in a stick built home.
Modular houses today are built in just about any style a conventional home can be, thanks to computer aided design and manufacturing. In the beginning, most modular homes were simple ranchers, with one floor and built with two "boxes". Today, two of the major manufacturers of modular housing that serve the Mid-Atlantic both offer over 50 different house designs, and wide variety of finishes, flooring and trim, from basic to luxurious. Designs can be custom built at the factory, and even additions to existing homes can made modular. Limiting factors are mostly location. Still, unconventional designs and use of heavy and brittle materials such as brick and stone are poorly suited to the manufacture and transportation of modular homes. The location must be accessible by the large tractor trailers that bring the modules in, and the cranes needed to set the modules in place. Sometimes, a heavily wooded lot, narrow streets or overhead utilities can be problematic. A backwoods location accessible by only a jeep trail would also be a poor choice for a modular. Zoning laws in some upscale communities may decree that new houses must be stick built, to prevent invasion by cheap manufactured housing, but quality modular housing is becoming more generally accepted.
I plan to add to the node as construction gets underway, and I hope to stop in at a plant does the actual manufacturing of modular houses.
Update December 23, 2003
I signed a contract in September, 2003 with a builder for Excel Homes, one of the larger manufacturers of Modular homes on the east coast. I was pleasantly suprised at the amount of customization of the floorplan that I could acheive. I was able to use the exterior of one model, the interior of another, and from there I stretched the interior dimensions to match the exterior dimensions of the first house. From there, I was able to modify the floorplan for stacked stairways, and also a raised roofline, which allowed for possible future expansion upstairs. I also made modifications for the laundry area as well.
Yesterday was set day for the new house, and I took the day off to watch. The foundation had been previously prepared and has been ready for 2 weeks. Excel is located in a rural part of Pennsylvania, and they closed for a week for hunting season, which delayed my house somewhat. The set crew arrived at first light, and a 60 ton crane arrived to lift the modules from the shipping trailers, which arrived Saturday. By lunch, they had both main modules set, the roof raised, and the gable ends installed. By the end of the day, the rest of the house, including a gable end porch and most of the roofing was installed, and the builder and I took a quick tour inside. There is still a lot of work to do yet, but the kitchen is ready for appliances, the carpets are laid, doors are hung and trimmed in many places, and walls are painted. Only a couple of minor cracks to repair. So far, everything looks good, and I was suprised at the precision that everything fitted together. With all of the changes and modifications that I made, along with the number of options that I could choose from, I was delighted that everything came through exactly as I had specified, and the house had a couple of minor upgrades even the builder wasn't expecting. I should be able to move in within a month, provided the builder stays on track and the power company gets its act together.
I have pretty much settled into my new digs. The house is solid and tight, and the floorplan is well thought out. My forecast of being able to move in by February 1 proved a bit optimistic, though the house was just about ready within a month but for one critical problem: Electricity. Lost paperwork, bureaucratic inertia, a hard winter, and problems negotiating with a neighboring landowner delayed my power until mid-March. In the meantime, I kept up on the new house's progress from the old place only a few hundred feet away, and moved what I could over in preparation for moving day in late March. Thankfully that is all behind me, and the builder has only sidewalks to complete, along with a few minor projects and repairs.
Reprint of 1927 Sears Roebuck Catalog
2001 North American Housing Corp. catalog