Modular construction is a great way to build an addition. You get the quality and price advantage that modular homes are known for along with faster build time. Speed is particularly beneficial when building an addition, since the construction will temporarily disrupt your family’s life, especially if you remain in your home while the work is being done.
Modular Additions: Attached and Second Story
Modular additions come in two types. The most popular type is attached to the side of a home to create either a separate living unit, such as an in-law apartment, or additional rooms, such as a new kitchen, dining room, and great room. Some customers build an in-law apartment at the same time that they build a new modular home. The second type of modular addition is set on top of a one-story home to make it into a two-story.
Modular Additions: Ensuring You Can Build
Before you spend too much time considering an addition, find out whether or not you can build one, and what will be required if you can. There are any number of issues that can prevent you from going forward. Not surprisingly, several of the issues that affect your ability to build an addition are the same as those that can restrict what you can do with a particular building lot.
Modular Additions: Covenants, Deed Restrictions, and Easements
When building an addition, you will be compelled to abide by any covenants and deed restrictions that apply to your property. Almost all subdivisions have covenants limiting what you can build, and a previous owner of the property might have placed a restriction on what you can do. Although covenants and deed restrictions do not usually address additions, the only way to know for sure is to check. You will also be prevented from building an addition on any part of your property where someone has an easement or right of way, unless you negotiate new terms that are recorded on your deed.
Modular Additions: Zoning Regulations
Local zoning requirements may affect several things you might want to do with your home. Setback regulations will prevent you from building an addition too close to abutting properties or the street, which could force you to build the addition on the side of your home that is less practical and affordable. If your property does not have a current survey, or if the boundary stakes are not in place, you may need to hire a surveyor before you can convince the building department that your addition complies with the setback requirements. It is unlikely the setback requirements will have much bearing on your plans if you are building a second-story addition.
Most communities have specific zoning regulations governing if and when you can add a second living unit to your home, such as an in-law apartment. Some require a special permit or a zoning variance for any two-family unit, regardless of use or size, while others provide an exception for an in-law apartment. Still other communities allow you to build only two attached single-family units on larger lots than are required for a single-family home. Zoning regulations can dictate how large a home you can build. Some communities restrict how tall the roof can be.
Modular Additions: Building Codes
Some building codes require anyone constructing an addition to upgrade their existing home to current building-code standards. For example, the building inspector might stipulate that you outfit your existing home with approved smoke detectors that connect to those installed in the addition.
Modular Additions: Module Access
In order to build a modular addition, the transporters, crane, and set crew must be able to set up in the proper location on your property. Even if your original home is modular, and access was not a problem when you built it, it is possible that you could run into a problem with the addition.
Modular Additions: Financing and Appraisal
Before entering into a contract to build an addition, determine how you will pay for it. If you intend to use a lender to finance the construction, you may have a choice of either an equity or a construction loan. To use an equity loan, you must have sufficient equity in your home, since the lender will only allow you to borrow against that equity. An appraiser hired by your lender will determine the amount of equity in your home. If you owe money on your home but the mortgage is small, the appraisal is less likely to matter, since the lender will have sufficient collateral even with a low appraisal.
If you have little equity in your home, and need a construction loan, the lender may require a down payment. It will also want an appraisal of your home that includes the proposed addition. Before you spend too much time exploring construction costs, speak with a couple of lenders to see what they can do for you.
When Modular Additions Are Not the Best Choice
There are times when it does not make good financial sense to build a modular addition. In general, it only makes economic sense to build a modular structure if the modules are reasonably sized and have some value-added features. A one-room addition, such as a great room measuring 20 feet by 27 feet 6 inches, does not meet these criteria. A small multi-room apartment, however, with a kitchen, bathroom, bedroom, and living room, such as a 22-foot by 24-foot in-law addition, does; for example see our Harmony 1, 2, and 3 in-law addition plans. As these examples show, size is not the only relevant factor. The great room is bigger than the in-law apartment, but it is full of empty space. This kind of structure is better built by a conventional stick builder.
Next week I’ll discuss the general contracting work required for modular additions.
For more information about building modular additions, see Building a Modular Addition in my book The Modular Home.
There are a few things you should know about reading and interpreting modular plans from dealers and manufacturers. In this blog I’ll discuss the exterior dimensions, interior dimensions, and square footage of modular plans. Keep in mind that these points apply equally to the house plans marketed by stick, log, and panelized builders.
Modular Plans – Exterior Dimensions
Modular plans typically list the exterior length and width as well as square footage of the home. The dimensions are almost always rounded-off, especially the widths. It is very common, for example, to list modular plans that are 27’ 6” wide as 28’. When modular plans are not an exact rectangle, manufacturers usually indicate the maximum width and length of the structures as if the modular plans were a true rectangle. For example, when a modular plan includes a 13′ wide bedroom that projects out from a section of a 28′ wide home, the manufacturer may list the width as 41′ even though the plan is only that wide where the bedroom is located. See the attached plan.
Modular Plans – Interior Dimensions
The interior dimensions of modular plans are always less than the exterior dimensions because of the thickness of the walls. To calculate the usable space you have to take these exterior dimensions into account. A room that is contained entirely within a 13’ 9” wide module will have an interior dimension of 13’ if the exterior wall is 6” thick and the marriage wall (where the modules join) is 3” thick. A great room that is created across two modules that are both 13’ 9” wide will have 26’ 6” of interior space because both 3” marriage walls will be eliminated.
Modular plans typically label the dimensions of irregular shaped rooms the same way they label the exterior dimensions of non-rectangular plans. They use the maximum width and length of the rooms as if they were true rectangles. This tends to exaggerate the size of rooms with jogged entries or closets that jut out from a wall.
Modular Plans – Square Feet
Many manufacturers use rounded-off dimensions to calculate the square footage of their modular plans. This will slightly inflate the size of these designs. However, modular manufacturers give accurate dimensions when they complete the drawings they use to build a modular plan.
Modular Plans – Verify What You’re Getting
The marketing literature for modular plans offered by manufacturers and dealers are is helpful when starting your search for house plans. But given the conventions for labeling dimensions and square footage, you need to take extra care to ensure you know what you’ll actually be getting before you authorize your home to be built.
For more information about calculating the exterior and interior dimensions of modular plans, see Designing a Modular Home and Modular Home Specifications and Features in my book The Modular Home.
Most modular home designs are one, two, or three modules deep and one or two modules high. A few companies build homes three modules high, although they require special approvals from the customer’s state to ensure they comply with the building code. Most homes are two modules wide, with typical widths of approximately 24 feet, 26 feet, 27 feet 6 inches, and 31 feet 6 inches. Three module wide homes typically range from 36’ to 47’ 3”. The usual practice is to place modules side by side, with the long sides parallel to the road. Some designs, especially when built on narrow lots, turn the modules perpendicular to the road. Modules can also be turned perpendicular to each other to create T-, L-, or H-shaped houses, which is one of many techniques the modular industry has employed to shed its image of making boring boxes.
Modular Home Designs – Minimum Size
Modular manufacturers will build homes only if they can sell them for a competitive price and still make a profit. The minimum order they will take is a function of the amount of labor and materials required to build the home. Too little labor and materials will make a home uneconomical to build at the factory. This means that small additions usually will not work financially, and neither will larger additions that are essentially empty boxes. For example, a 16 foot by 27’6” foot great room addition is usually too small and devoid of value-added work to make economic sense. On the other hand, a 24-foot by 24-foot in-law addition with a kitchen and bathroom can work nicely.
Modular Home Designs – Adding Length
Adding length to a modular home is always easy to do from the manufacturer’s point of view, as long as it stays within the maximum production and delivery dimensions. This is also true about adding bump-outs to the end of a module, such as a walkout bay. Making a plan of a given size bigger by adding to the length of the modules is one of the best values in the entire construction industry.
Modular Home Designs – Adding Width
Increasing the size of a particular plan by widening the modules is also a very good bargain. The cost per square foot is often a little more for adding width than length, because the floor system sometimes needs to be beefed up; for example, from 2 x 8 floor joists for a 24-foot-wide home to 2 x 10s for a home with a width of 27 feet 6 inches. Widening a module, like lengthening a home, will always add more equity to a home than it costs.
Modular Home Designs – Adding a Bumpout
Adding a “bump-out”, such as the walk-out bay, to a long wall on a module that is already at its maximum width is more involved than adding one to the end of a module. The manufacturer must either build the bump-out as a separate miniature module or ship the necessary materials to the general contractor.
Modular Home Designs – Using a Saddle or Cricket
Attaching one or more additional modules perpendicular to the long side, as discussed above can also enlarge a standard plan. This will require that a “saddle” or “cricket” be built to join the roofs.
Modular Home Designs – Adding a Second Living Unit
Another way to enlarge a home is to attach a separate living unit to the home, such as you might do to create an in-law addition or a two-family unit. The second unit can be designed with either a custom or standard plan.
Modular Home Designs – Additional Delivery Fees
When enlarging a given plan, make sure that any additional delivery fees are included in writing. Increasing the width up to 27 feet 6 inches should incur a relatively small fee. The fee for widening a home to 31 feet 6 inches, however, will be more substantial. Adding length to a home will sometimes require additional delivery carriers, which also can add significantly to the cost. This will happen when the original length of the house calls for delivering two modules on one carrier but the new, longer plan requires delivering the two modules on two carriers. Consequently, the new design will require an additional carrier for each pair of modules. For example, if a manufacturer’s maximum length for shipping two modules on a carrier is 30 feet per module, it can deliver a two-module-wide 28-foot-long in-law apartment on one carrier. However, if the apartment is lengthened by 4 feet, making each module 32-feet long, an additional carrier will be needed. When the original plan is a 28-foot-long two-story that is being lengthened to 32 feet, two additional carriers will be needed.
Additional carriers will also be required whenever lengthening a home makes the modules too long for the manufacturer and general contractor to deliver to a site. For example, a narrow road to the site may make it impossible to for a longer carrier to negotiate the turns. The only solution, other than keeping the home at its original length, might be to have the manufacturer divide each longer module into two shorter modules. The manufacturer will charge more to do this, but it may be the best way to get the home you want.
Modular Home Designs – Additional Option Costs
Enlarging a home will also increase the cost of any options that are affected by the increase. For example, upgrading to a premium siding will cost more when a home is made wider or longer, since more area needs to be covered. Other optional features will only increase in price if a particular room increases in size. For example, a dining room wood floor will only cost more when a home is lengthened if some of the additional length is put into that room. Increasing the size of a particular room can also force you to add windows or doors to meet the building code, which requires a minimum amount of “light and vent” for each room.
For more information about modular home designs, see Designing a Modular Home and Modular Home Specifications and Features in my book The Modular Home.
Are you considering having your parents move in with family? If so, are you considering building an “in-law” addition to your home to provide them (and you) with a private space? Perhaps you are even considering making it a temporary addition, which can be removed when you no longer need it. Unfortunately, you probably will need to build your addition as a permanent structure, since very communities allow truly temporary additions. It’s not been for lack of trying, however. Here’s a little history.
Elder Cottage Housing Opportunity (ECHO)
It started with the fact that families are sometimes prevented by local zoning regulations from building an in-law addition in single-family neighborhoods. There are several reasons why communities pass regulations that exclude such in-law apartments. The two most common are to preserve property values and safeguard neighborhoods from transient residents. In the early 1980s, the American Association of Retired Persons (AARP) proposed a zoning solution that would respect these concerns yet allow families to build an apartment for their elderly parents. The proposal became known as the Elder Cottage Housing Opportunity program (ECHO).
The core idea of the ECHO program was to allow a family to build an in-law apartment on their property as long as they agreed to remove it once their parents moved on. After the temporary addition was removed, the property would be restored to a single-family residence, bringing it into compliance with the community’s zoning restrictions. To make this possible, the temporary addition would either have to be discarded or relocated. Virtually all advocates of the program recognized that a modular home would make it possible to relocate and reuse the apartment each time the occupants vacated it.
In theory, the ECHO program worked on multiple levels. Many families who want to help care for their elderly parents are not looking to create a permanent in-law apartment. They do not want to maintain it or pay the additional taxes, they are not interested in becoming landlords after their parents no longer live there, and they would like to reclaim that part of their yard that has been taken over by the apartment. On the other hand, they do not want to dispose of an in-law apartment that is in usable shape. They would prefer to recoup some of their investment by perhaps passing the apartment on to another family who needed it.
Unfortunately, the ECHO program has yet to take hold. The necessary zoning regulations have not passed. Fortunately, many communities already have zoning regulations that allow for a permanent in-law addition. And they also allow for these structures to be dismantled in the future, as long as you obtain a permit and comply with the regulations. The one caveat, however, is that you must build the temporary addition as if you intend to keep it as a permanent apartment. This means it must comply with all building codes that apply to a new residential home.
Temporary Modular Addition
An advantage to using a modular home for a temporary in-law addition is that it can be disassembled into a few intact sections that can be easily relocated. This is seldom a viable option for a stick-framed addition. The disassembly of a modular temporary addition requires that the general contractor (GC) carry out the same steps he executed to button-up an addition, but in reverse. This should take considerably less time and cost considerably less money than the assembly. The GC would likely need to do the following:
( ) Disconnect the plumbing, electrical, and heating systems
( ) Remove the siding where necessary
( ) Separate the modules at the marriage wall, inside and outside
( ) Lower the roof on each module
( ) Lift the modules off the foundation with a crane and crew
( ) Place the modules on rented transporters that have all of the necessary permits
( ) Deliver the modules to their next home
( ) Restore the property to its original condition, including removing the foundation
The disassembly of the temporary modular addition will render some of the materials unusable for the next owner. Some of the shingles will need to be replaced, for example, as will some plumbing and heating components installed in the basement. If you are buying your modular addition directly from a modular manufacturer, consider buying extra materials so the next owner will have matching replacements when it comes time for them to reassemble the addition.
For more information about Elder Cottage Housing Opportunity (ECHO) Temporary Modular In-Law Additions, see Building a Modular Addition in my book The Modular Home.
Remodel the Inside of Your Existing Home When Building a Modular Home Addition
To make the floor plan of your current home flow nicely into your modular home addition, you may need to do some remodeling. If you add a second-story modular home addition, you will certainly need to build a set of stairs to the second floor. But you may also want to rearrange your current floor plan. You might remodel your home to update some features; kitchen and bathroom renovations are particularly popular choices. Or you might remodel to improve the layout. When building a second-story modular home addition, for example, you might accomplish this by making two of the existing bedrooms into a great room or by carving out a bigger kitchen and formal dining room. When building an attached modular home addition that contains a new master-bedroom suite, kitchen, and formal dining room, you might make the old country kitchen into a breakfast nook and mudroom.
Dress Up the Front of Your Existing Home When Building a Modular Home Addition
You may want to use the modular home addition as an occasion to dress up the outside of your home. In fact, you might not have a choice, since the siding, shingles, or windows may need to be replaced to match the addition. Replacing or refinishing all of these materials in your existing home can be expensive. On the other hand, it might be the perfect time to do so if they are worn out.
Add a Deck or a Porch When Building a Modular Home Addition
Building a modular home addition is often the perfect time to add the deck or porch you have always wanted. It is usually more affordable to do these small projects while a general contractor is already completing the other work at your home. Your lender may also be willing to increase your mortgage by the relatively modest amount needed to take on these projects.
Remodeling Can Be Expensive, Even When Building a Modular Home Addition
Remodeling, however, can be expensive, and the true cost is often hard to pin down in an older home until the work has begun. If you are having a GC do some remodeling, you will want to understand what he is assuming responsibility for doing and what he is excluding from his contract. You will definitely want to set aside a good-sized contingency fund.
For more information about modular additions and remodeling, see Building a Modular Addition in my book The Modular Home.