As a real estate appraiser, I've come across a variety of home types in my career, each with its unique characteristics, construction methods, and financing options. One common area of confusion among Realtors and buyers alike revolves around the differences between manufactured homes, modular homes, mobile homes and site-built homes. Understanding these distinctions is crucial not only for proper valuation but also for guiding clients through the buying or selling process. Correctly categorizing them in the NWMLS is key to having a good quality data, when doing an appraisal. In the PNW, including Island, San Juan, Skagit and Whatcom counties, Manufactured, Modular and Mobile homes are not uncommon. Here, I aim to clarify these differences and provide insights into how each type is appraised.
One of each is in the photo collage below. Can you tell which is which?
Manufactured Homes
Manufactured homes are entirely constructed in a factory and then transported to a site where they are placed on a permanent foundation. Here are the key points Realtors should note:
**Construction**: Manufactured homes are built on a non-removable steel chassis, with one or more steel "I"-beams, that run the length of the structure. They generally come in single, double or triple-wide configurations. Manufactured homes must be built to a minimum standard set by HUD code. Manufactured homes will also have "HUD tags" on each section of the home. These are metal tags that identify the section. There will also be a "Data Plate", which is a 8.5' x 11' paper mounted on the inside of a cabinet, that identifies the manufacturer, model, and serial numbers, among other info.
Below are a sample Data Plate on the left and an actual HUD Tag on the right. 
Modern manufactured homes can be quite stylish and comfortable. In fact, FNMA has a program called the "Manufactured Home Advantage" program. Manufactured homes that qualify are built to meet construction, architectural design, and energy efficiency standards that are more consistent with site-built homes. To the untrained eye, you almost can't tell them from a stick built/site built home. The home below is an existing Manufactured Home Advantage home appraised by the author.
**Appraisal Process**: The appraisal of manufactured homes is on a specific FNMA manufactured home form and focuses on factors like the home's age, size, features, like a traditional appraisal, but the Appraiser must include at least 2 manufactured home sales. For Manufactured Home Advantage homes, the Appraiser can compare the subject to stick built/site built homes, if there are no Manufactured Home Advantage sales.
Modular Homes
Modular homes are also factory-built in sections or modules, which are then transported to a building site and assembled on a permanent foundation. They differ from manufactured homes in several key areas:
**Construction**: Modular homes must comply with local building codes, not the federal HUD code. This means they can be similar in quality and design to site-built homes, with a wide range of architectural styles and customization options. They can range from a simple, rectangular design with modest materials that is virtually indistinguishable from a manufactured home to high quality factory built homes, with modules built with recycled materials.
The image to the left is a modular home built by BluHomes.
Here in WA, modular homes will have a small metal plate, usually mounted near the front door, which signifies they are a modular home. To the right--->is an example of a modular home label from the state of WA.
**Appraisal Process**: Appraising modular homes is more akin to appraising site-built homes. The GSEs require the Appraiser to complete the appraisal on a typical single family appraisal form, and not a special form, like manufactured homes. There are far fewer sales of modular homes and, at times, they are not categorized or identified properly in the NWMLS, making the appraisal process more challenging, but, because the Appraiser uses traditional, stick built homes for comparables, the issue is more about finding a sale of similar quality and size, just like an ordinary appraisal..
Mobile Homes
More commonly located in a park with a leased site, (but not always) mobile homes are on a permanent metal chassis, these homes were designed to be movable, though many end up stationary. It is not uncommon to see these structures in WA as a 2nd home or "Accessory Dwelling Unit" on a site.
**Construction**: These homes can vary widely in materials, but most have metal siding and an aluminum, asphalt or TPO membrane roof. Generally the quality is at the lower end of the spectrum. They often rest on piers or an anchoring system without a permanent foundation.
**Appraisal Process**: Many Credit Unions, private money lenders and banks offer financing for mobile homes, as the GSEs do not. There is a special Mobile Home Appraisal form that is used. Generally sales are much more difficult to find, making the appraisal process challenging.
There is a very interesting market, Lake Tyee, in Concrete, that has many mobile and a few modulars. To the left is a mobile home in Lake Tyee appraised by the Author. Notice the lack of a foundation.
## How to Tell Them All Apart
Identifying whether a home is manufactured, modular, or site-built can sometimes be challenging, especially with newer models that have advanced in terms of design and construction quality. Here are some tips:
**Look for Labels**: Manufactured homes have a HUD label displayed outside the home, indicating compliance with federal standards. A modular home with have a WA state Dept. of Labor and Industries gold plaque, usually near the front door.
**Check the Foundation**: Manufactured homes can have a concrete perimeter foundation or they can be on a slab with piers. They will generally be distinguished by a large steel "I"-beam under the chassis. Modular and site-built homes are on permanent foundations.
**Review the Documentation**: The property's original documentation should indicate whether the home is manufactured, mobile or modular. This includes building permits and certificates of occupancy.
If you have a question as to what a structure really is, contact me! As a Certified Appraiser, having appraised all of these types of structures, I can help. It doesn't matter if it's my deal or not, I'm always ready to be of service.
Understanding the nuances between manufactured homes, modular homes, mobile homes and site-built homes allows Realtors to provide better services to their clients and allows them to correctly input these properties into the NWMLS. By recognizing the key differences in construction, style, financing, and appraisal methods, Realtors can navigate our diverse housing market with confidence, ensuring their clients make informed decisions.
If you have gotten this far, I'm glad you made it. Please leave me a comment below.
Anthony Blackburn is a Certified Real Estate Appraiser at San Juan County Appraisal, serving the San Juan Islands and surrounding mainland counties.
Estate appraisal, tax appeal appraisals, private lending appraisals, divorce appraisals.
I am always available for any real estate appraisal related questions, whether it's my deal or not. I'm always happy to have a conversation. (360) 627-0208 or ablackburn@sjcappraisal.com
You can also find me on social media
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