Modular Additions

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.

An ECHO modular in-law addition added to the right side of this modular T-Ranch
An ECHO modular in-law addition has been added to the right side of this modular T-Ranch

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.

It's impossible to tell from this photo that this was a ranch made into a two-story with a second-story modular addition.
It’s impossible to tell from this photo that this was a ranch made into a two-story with a second-story modular addition.

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.