When you are remodeling your home, there may be a plumbing component to the job.
Many homeowners ask, "Can I do this work myself, or should I call a plumber?" Even for a competent DIYer who has learned by experience and by watching online tutorials, there are many jobs that are better left to the pros.
Additionally, you get the greatest in design freedom if you have a plumber in the mix who can reroute existing water and sewer lines or update old pipes.
How To Decide If You Need To Call A Plumber

1. The job requires skills the average homeowner lacks.
   Professional plumbers undergo training and apprenticeships to acquire their skills and knowledge.
   Their work meets local building codes, and will be professionally completed so that the next plumber who works in the house will not have to redo the work.
   The mistake that many DIYers make is to take shortcuts that may "makes sense," but violate city codes.
   You might select the wrong type of material, improper dimensions, or incorrect fittings - and potentially even fail to install them correctly.
   Even if your work seems to do the trick initially, you may face a busted pipe down the road because your new pipe couldn't handle the pressure.
   If you call in a professional at this point, you may find yourself paying not only for the repair, but for other damage to your home as well.
   
2. The job requires having and knowing how to use specialized equipment.
   You may have common tools such as wrenches, pipe wrenches, drain snakes, and soldering guns in your toolbox but it's unlikely that you own heavy-duty equipment to auger out drains and do other big jobs.
   For example, if you have a main line stoppage that results in toilets backing up into showers and tubs, you can rent the proper equipment for a day, but you will spend part of the time learning how to use it.
   When you are working on something that is pumping sewage into your home, it's not the time to stop and learn the basics about operating the equipment.
   
3. The job requires a permit from the city.
   When you add an addition, remodel a kitchen or bathroom, reroute existing plumbing, or even add a gas line for your grill, you need a permit from the city.
   As a homeowner, you may attempt to undertake some of these things yourself to save permitting costs and tax increases on the assumption that the city is none the wiser.
   This strategy can backfire on you, as the final work will have no inspection verifying that it is up to code.
   When you go to sell your home, the city might require you to tear down unpermitted work.
   
4. The job is complex and may have repercussions to other systems in the home if done incorrectly.
   Just as the systems in your body are connected, so are systems in your home.
   A professional plumber can assess what needs to be done and recommend if you need to call in another trade professional to work on the job.
   For example, big jobs like replacing a bathtub might require reinforcing the floor; something a weekend DIYer who wants to get the job done quickly, might not think of or bother with.
   
5. You need freedom of design.
   When doing a major kitchen or bathroom remodel, you may find that your kitchen would function better if the sink were in the island, or that you would have more room if the toilet could just be moved over 6 inches.
   Jobs like this require rerouting the plumbing to make the most of your remodeling job.
   While you might just remodel around poorly placed pipes, a professional plumber offers the design freedom to dream!

Using a professional plumber will assure that the job is done right and up to code, minimizing risks for future problems and code violations.
In the case of remodeling, a professional can make recommendations and reroute existing plumbing to give you greater design freedom and the exact layout you want.