Building Your Dream Home: Rough-In

Building Your Dream Home: Rough-In

Home | Blog | Building Your Dream Home: Rough-In

Building Your Dream Home: Rough-In

Published at May 03 2024 by JFord

There’s a flurry of activity on your work site this week. Your builder has called in three different subcontractors and you can barely pull in the driveway around their trucks. What is going on? Did something go wrong? Wait, is that the building inspector? Why are they here?

House plan featured above is our Ambrose Boulevard (NDG 953) plan.

Nothing is wrong. Everything is fine. It’s just the point in the project that you start doing the rough-in. In construction, the term “rough-in" describes the stage in the construction process when the mechanical wiring, plumbing and HVAC is installed.

This is after the framing is done and before any of the real flooring and wall coverings get put in. It’s also one of the important times for inspections. Every step of this process will be inspected and have to be checked off prior to the next one.


The Process of Rough-In

This is a strange process to describe. It’s both fluid and totally dependent on other pieces and processes being done before workers can proceed. Most of the work that has been done on your home prior to this has had a very linear focus. “This step is done. Now you can do this next step." That kind of thing. The rough-in happens simultaneously as other parts of the building process and is also sometimes dependent on something that came before it.

One of the things your builder or, if you are building your own home, will need to do is to meet with all of the subcontractors before any of this work begins to plan out how all the pieces are going to fit together. Building a house is kind of like doing a jigsaw puzzle with about 15 other people. They each have their own pieces that go in and some of the pieces have to be put in before the others.

You’ll meet with the people doing your plumbing, electrical and HVAC work before any of them get started with the rough-in work. They will want to plan how they are putting their pieces into place. If you have a home that has an open floor plan, then they are going to have to discuss how to utilize the minimum amount of space possible for each of their jobs. Duct work takes up the most room, so HVAC gets the priority in these conversations.

It’s not just the plumbing, electrical and HVAC that gets done at this time; some of the other things that get done are just part of the building process. One thing that may happen at this point in the construction is that your home may be sprayed with a chemical to make it inhospitable to termites. The builder may also have insulation put in in places that it would be difficult to reach after other work is done. If you are having skylights or anything like that put in, they would do the preliminary work now.



One of the parts of the rough-in process that can be looked at this way is plumbing. A plumber is going to be on your build site almost from the very beginning. They may be skilled in the way the water is moved around your home, but they also need to have a lot of general knowledge about how the house is being constructed and the steps involved. A good experienced plumber will have this knowledge and know exactly when he/she is needed and what they need to do.

Foundation Work

The plumber will be there when the foundation is being prepped and poured. They will need to make sure that the pipes are in place, especially if it is a slab foundation. At this point they will also make sure that you have a connection to either a septic system or to the city sewer system. They will also bring the water line in and cap it at this point. The last step at this stage will be to make sure that your home has a drain line in place. This is described as their stage 1 rough-in.


The next stage of the process doesn’t begin until after the house is framed up and the HVAC duct work has been done. You’ll need the house to be “dried in". This means that the roof is completed and that all of the openings for the windows and doors are covered and they may even have those installed. You can’t make glue stick together for pipes if there is water dripping from the roof. You also can’t finish the roof until the HVAC has been done so that flashing has been put into place before the shingles are put on. More about that later, though.

Your builder, or you, will also need to walk the house and mark everywhere that cabinets will be on the floor. This will let the plumber know where to run the pipes. If you are having gas lines installed, the plumber will take care of this as well.

There are a couple of things that need to be done during this stage for the plumbing to be done properly. All of the water lines into and out of the house need to be run. Any line that is coming in needs to be capped until it is ready for the fixtures to go on it. The plumber will bore holes through the studs of the house for the pipes and install and connect the pipes. No fixtures or end elements will be connected right now. That will be after the drywall and everything is installed.

The plumber will put in the water lines and drain lines to every room of the house that is going to need it. That means every sink, tub, shower, washer, dishwasher, etc. The pipes will be run under where the flooring will be and along the walls. The last thing that will be done by the plumber at this time is to install the tub.

Bathtubs are heavy and bulky and hard to move. They are also very hard to predict the size of. Plumbers put the tubs in now because it is easier to maneuver them without walls in the way. Once the tub is in place the plumber can fill it and make sure that all the pipes are in their proper places.

Last Checks

After all of the pipes and everything has been run and capped, the plumber will test all of the lines that he/she has installed. There are two ways to test to make sure that piping is secure and will handle the pressure running through it. The first way to test it is to use water pushed the pipes. The second way, the less messy way, is to use an air compressor.

electrical rough-in


An electrician is like a plumber in that they will be on the work site for different parts of the process. They need to understand the different phases of the construction process and know when they will need to have their work done.

Foundation Work

Like a plumber, an electrician will be on hand before the foundation is put in on your home. They will be there to hook up to the electrical grid and make sure that everything is ready before the foundation is put in. They might even have to run some lines underground and up into the area where the foundation will be.


Just like plumbing, this is when the majority of the work is done on the inside of the home. All of the wires and cables will be run through the home. Anywhere that you will need an outlet, a light switch, etc., they will put the wires in now.

Each of the wires will have two open ends. The ends that will be connected to the breaker box are labeled and left hanging where the breaker box is going to be put. The other end of the wire is run to the location where it is going to be used and put through a box. These electrical boxes mark where the outlets and such are going to be. They also protect the bare wires from the insulation.

Final Check

The last check for an electrician is to make sure that all of the wires that the home needs have been pulled through and put in their proper locations. The electrician will also want to make sure that all of the wires are reading for the right levels using an altimeter.



Heating, ventilation, and air conditioning is the last part of this process. Or maybe it’s the first. It’s really hard to tell with all of these. Unlike plumbing and electrical work, the HVAC work is not necessary through the beginning of the building process. His/her work doesn’t start until after the foundation is laid and the frame of the house is put into place.


The contractor working on the HVAC for your home will have to run duct work for all of the rooms that you want heating and cooling in. Ideally, that is all of the rooms in your home. I know that my hallway bathroom doesn’t have a duct in it and it can be almost unbearable in there during the summer time. My house was built before central heat and air was a normal thing.

The ventilation system has to be put in during the roofing process. The roofers can’t put the shingles on the roof until after the ventilation shafts are put in. The HVAC technician will put this after the flashing is put in, but before the roofing material is put on. If your home has an open floor plan, then the HVAC technician will have to use any available space to put in the duct work.


All of the rough-in work should be completed before a building inspector comes in to look at the property. A building inspector will come in and check the work for the plumbing, electrical and HVAC. Each one of these will have their own inspection and will need to be signed off before anything else can be done to the house. If the work fails, then it will have to be corrected before anything else can be continued.

Last Steps

Here are some of the most important checks that a general contractor, or if you are building your home you, will need to make to ensure the quality of the rough-in.

  • Review all trusses, beams and girders. You want to make sure that nothing was cut out or notched.
  • Joists/I-Joists. You want to make sure that these were cut and notched according to the manufacturer’s recommendations or code requirements.
  • Check Drains and Supply Lines. Make sure that all of the drain lines are clear and installed properly and that all of the supply lines are as well.
  • Nail Plates. You want to make sure that these metal protective plates have been installed where the supply lines pass through studs and plates.
  • Review the vent flashing on the roof. Vent flashing helps keep out moisture and pests, so you want it to be installed properly.
  • In cold climates, you will want to make sure no water supply lines were installed in any exterior walls.

Remember, this is going to be your home. Going in and looking at the work is something that you’ll want to be doing an every phase of the construction process.

If you’re still in the planning stage of building a home, check out our other blogs in the homebuilding series:

Nelson Design Group has over 1,800 house plans available and most are customizable to your needs. Give us a call today!