Can an Addition to a Manufactured Home be Included in the Living Area?

We recently had this question asked of us and thought it might be great to address it here as the teacher in me believes that if one person asked a question then there are others that may have the same question.

Appraising manufactured homes are a bit different from traditional stick built homes as there are a few different guidelines and requirements to follow.   A manufactured home is not built on site but in a factory. They are subject to Federal Building code (HUD) rather than the local building code.  They are built on a steel chassis and transported to their destinations.  Homes built after 1976 are considered manufactured homes when stricter federal guidelines HUD codes were enacted.  Homes built prior to that are considered to be mobile homes.  Some will use the terms interchangeably but they are different.  Manufactured homes are of higher standards and quality than mobile homes due to the HUD codes.  Manufactured homes can be an affordable choice for consumers that own their own land but are priced out of the traditional new home construction market.

Homeowners of both manufactured homes and traditional stick build homes will often make improvements such as an addition to the original structure.   The question is can this addition be included in the GLA (gross living area) of the home?   The answer is yes if the following conditions exist:

1. The addition is in keeping with the design, appeal, and quality of construction of the original structure. The appraiser will observe the addition and it should be of similar quality as the home.  If it is of inferior quality, design and appeal this addition will not be counted in the living area.
2. The addition has proper functional utility.  This has to do with the functionality of the addition. If a bedroom is only accessed by walking through another bedroom, this would not be functionally acceptable.  If a room is only accessed through the garage, this would not be functionally acceptable.
3. The addition must have a permanent sufficient heating/cooling source.  If an enclosed porch is only heated and cooled with a window unit and a stand alone electric heater, this would be a sunroom or enclosed porch but would not be counted in the total living area.
4. All of the above will apply to additions for both manufactured homes and traditional stick built homes.  For manufactured homes both FNMA guidelines and HUD guidelines require an engineer's report to certify the structural integrity of the addition and that the structural integrity of the manufactured home has not been compromised. 

Also, if you have a manufactured home please do not remove the HUD Data Plate/Compliance Certificate or the exterior HUD Certification Label. The HUD Data Plate/Compliance Certificate is typically located in an interior closet door or kitchen cabinet.  The exterior HUD Certification Label is a metal piece attached to the outside of the home.  Appraisers have to locate these and obtain information from them.  If these are missing you will have a difficult time selling or refinancing your manufactured home.   Here is what they look like: (photos are intentially blurred)

HUD DataPlate/Compliance Certificate (interior)

HUD Certification Label (exterior)

In conclusion, an addition to a manufactured home can be included in the GLA if the four conditions above have been met. If you have any additional questions or concerns please feel free to contact us or contact your local appraiser for questions regarding your manufactured home addition.

Here are some great resources you might find helpful:


Manufactured Home Property Eligibility Requirements -  Fannie Mae Selling Guide

HUD Guidelines - Single Family Housing Policy Handbook, 4000.1

Four areas the appraiser will not include in the GLA- Tom Horn, Birmingham Appraiser Blog

What is the difference between a manufactured and modular home?- Ryan Lundquist, Sacramento Appraisal Blog

What are the Differences Between Manufactured, Modular, and Mobiles Homes?- John Fedro, Bigger Pockets


Disclaimer: All information deemed reliable but not guaranteed. The information is meant entirely for educational purposes and casual reading only and is NOT intended for any other use.  This information is NOT intended to support an opinion of value for your appraisal needs or any sort of value conclusion for a loan, litigation, tax appeal or other potential real estate or non real estate purpose.  If you’d like to obtain additional information or order an appraisal for your specific needs, please contact us at www.dwslaterco.com.