By Larry Garnett

Home Additions

From: Sue

"Carl, we are thinking of adding on to our present house. Where do we start? Should we call a remodeling contractor to get ideas & plans? We need more space! Help!

Sue"


Hi Sue,

There are two basic ways to add to your home. One is to make habitable an existing unfinished area such as a basement, garage, screened porch, breezeway, or attic. This is the least expensive way because you already have the basic room with a foundation and some or all of the outside walls.

The other and more expensive way to create home additions is to build on to your house. If you are considering this, check to see that you have room on your lot without violating required setbacks and that you meet any subdivision or deed restrictions. Check with your local building inspection department and, if you have one, your homeowners association.

If you don't have an existing "mortgage report" survey, it is well worth the money to get one...should cost about $150-200.

Once you get plans for your home addition, it should be 1st drawn onto the survey to be sure it fits. If it fits on paper, it will fit in reality. If it violates setbacks, adjust your plans accordingly.


Typical Mortgage Report Survey

You always start with a budget, even if you're as rich as Bill Gates.

Budget = cash + borrowing power.
For borrowing power, talk to a mortgage lender of your choice.


As for calling a remodeling contractor for plans and/or ideas, you certainly should. Get bids from at least three remodeling contractors. Be sure to clearly state your budget to them. Be sure to get at least three references and, CHECK THEM!

I would also consult with a local design firm. You can find them in the yellow pages under “home designing and planning service”. Explain your budget to the designer. They, as professional designers, should know how to design to your budget. Be sure to get at least three references and, CHECK THEM!

Here's a nice addition from CADSmith Studio, LLC
This 22' x 22' addition is suitable for a traditional 2 story or cape style home.
1st floor Living space: 484 sq. ft.
Conventional floor and roof framing


For more photos, click on picture.


Courtesy of CADSmith Studio, LLC

I ran a cost analysis on the cost to build calculator (#5 on my “Getting Started” page on www.byoh.com)

Using Grand Rapids, MI as a random city, I came up with $46,734 total cost without the General Contractor markup, which will be higher than normal as explained below.

Breakdown of Building Costs For This Home Addition. (PDF)(You will need Adobe Reader to read this cost breakdown.)

Here is a FREE Adobe Reader download if you need it.)

You should keep in mind that the cost to build for this example, or any house plan, can vary considerably depending quality of materials selected, and on actual bids for labor and material.

As you can see, building an addition is like building a small house, and just as in building a house, you can act as your own General Contractor and estimate the costs based on you hiring your own subcontractors (tradespeople) and buying the materials needed.

The basic difference in estimating an addition against a complete home will be the increase of some square footage building costs due to the smaller size of the job. Subs may want a few more dollars for their labor because they could be earning more on a larger job for almost the same amount of time.

The general contractor that you won't be hiring because you're doing it yourself would also have charged a greater percentage for profit and overhead. As I mention in my book, the National Association of Home Builder recommends that professional builders aim for a 50 percent gross profit margin on home additions and remodeling! The savings you realize by being your own general contractor will more than offset the increase in labor costs from subs.

You should make a list of all the materials the project will need and use a cost estimate spreadsheet from www.byoh.com as a starting point. Obtain competitive bids as though you were building a house and proceed from there.

NOTE: Don'’t add too much value to your home. Sooner or later, all houses need to be sold, and you don't want to have the most expensive house in the neighborhood when you put it on the market. It's a real estate fact of life: The most expensive house in the neighborhood is very difficult to sell. Before even deciding to go ahead with the addition, get an appraisal or market analysis from a Realtor as to the completed value, or the value of the addition added. If you are getting a loan, your mortgage lender will most likely have an appraisal done before deciding to lend you money.