How to Build a Room Addition With Contractors

Building Looking at Room Addition Under Construction
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A room addition just might be the solution to your space problems. Less than a full-blown addition, more than refurbishing existing space, room additions suit the needs of many homeowners, both in terms of space and costs.

Seasoned contractor Larry Mock, owner of Portland Oregon's Cascade Custom Remodel & Construction, offers advice on building a room addition. Mock has four decades of experience in the construction industry.

Even Contractors Want You to Get Other Bids

Though it seems preposterous, most contractors do not want you to hire them for a big job if you are not 100 percent certain. If you jump on the first contractor that comes your way, you may get cold feet later on. Contractors do not want to be the first one that you choose; instead, they want to be the chosen result after all of your careful research.

Mock suggests interviewing three to six contractors and checking on the outcome from the last number of projects the contractor has completed. He also recommends checking HomeAdvisor and LinkedIn for reviews.

Too Many Bids Can Be Too Much

Soliciting more than five or six bids wastes time--your time and the contractors'. Mock says he won't submit a bid if there are more than two other contractors competing for the job.

Good Bids Will be Closely Clustered

If you have chosen the contractors well, most of the bids will be fairly close within the same range. Says Mock: "In my 40 years of remodeling, contractors who have the same passion and determination as we have, are generally very close to our price."

Be Careful of Really Low Bids

When you get that too-low bid, this may be an indication of a problem. It may not necessarily indicate a scam operation. It may just mean that the contractor doesn't fully understand what you want and is bidding based on a scaled-down idea of your vision. Mock recommends: "The last thing a homeowner wants is the lowest price or a contractor who goes out to bid to get the lowest price in each category. This is a recipe for disaster."

Exhaust Other Options First

Room additions are not your first option; they are your last option. Due to the price and complexity of building a room addition, you should exhaust every possible solution to your space and living issues before undertaking this project.

  • Declutter: There is a structure that is about 12 feet long and 8 feet wide that is far cheaper than any room addition you can build. This structure is called a roll-off container, or Dumpster. Fill that with unneeded household detritus before even considering a room addition.
  • Rearrange, organize: Closet organization systems work wonders for cluttered bedrooms.

You Must Be Able to Work With the Contractor

With a room addition, getting the contractor right is essential. Your ability to work with a contractor hinges on how well your personalities mesh. But do not expect to become great pals during this project; this is primarily a business relationship.

The main issue is the contractor's reputation and how the owners feel about them. After all, that contractor is going to become a family member for the better part of 4 to 16 weeks depending on the scope of work. So having a contractor with a great rep and that they feel good about can lead to a successful project for all concerned.

Sunrooms Are Not an Acceptable Substitute

No doubt about it: sunrooms are attractive. They cost less than full-scale room additions, and they give you just as much square footage. But sunrooms are just that: sun rooms. Most do not have plumbing, showers, bathtubs, toilets, and other essential services. Most significantly, they are usually not conditioned (heating and cooling). Build a sunroom if you want a conservatory-type feel, but not because you think it will substitute for a real addition. 

Consult a Realtor or Appraiser

Are you putting on the room addition purely for your own benefit? Or do you care about resale value when it comes time to sell? Even though you cannot do things just for the benefit of some nameless, faceless potential buyer sometime in the distant future, you do need to give some thought to resale value. Not all room additions give back adequate resale value.

The realtor who sold the home to you will be more than happy to tell you how this added square footage (and the type of square footage you’re considering) will benefit you in the long run.

Realize That You Are Building a Mini-House

A room addition involves all of the same things that you find in new home construction: foundation, footers, framing, zoning, permitting, HVAC, flooring, plumbing, electrical, new windows, and more. The list goes on and on.

Even if you are building a great room or living room (i.e., a room addition without services such as plumbing), you still have other services that you cannot avoid (electrical, heating, cooling, and more).

Think in Terms of Square Footage Cost

Building an addition is complex. The only way to make sure you are comparing contractor estimates on a level playing field is to compare on a dollar-per-square-foot basis. But you’ll want to make sure that all contractors are bidding on the same thing, or your square footage cost comparisons will be all wrong.

Timing can be a big issue. Check with each bidder to find out what their schedule and availability is. Most good contractors will have a backlog of work.