4 Stages to Building a Home Addition

A home addition can be an extremely exciting project, particularly if you have been dreaming of expanding your house for some time. It can also be overwhelming when you realize exactly how much work it entails. After finishing tasks associated with pre-construction, such as determining desired outcomes of the project, floor planning, and signing a contractor, the actual building process can begin. Although every project is different, there are four stages that are common to most home addition projects.

The Shell

The first phase of construction when building a house is constructing the shell, which is essentially the skeleton of the house and what keeps the weather out.

It includes the structural members (masonry, framing), the exterior surfaces(siding and windows), and the water drainage systems (roofing and gutters). The footprint of the shell is usually determined in the initial design phase so there aren’t any holdups while it’s being constructed. It also has to be strong enough to support everything that’s going to be built on top of it.

After the structure has been framed and papered in from the elements, the contractor will walk the client around the entire home and point out any structural changes that might have to be made as well as any exterior changes the homeowner would like to make. These can include changes such as roofing and siding color, adding decorative elements to the exterior such as shutters, or wider trim. The contractor will then address any concerns that the homeowner may have.

Constructing the shell is the most visually productive part of the process and usually gets the most attention by friends and neighbors because of the dramatic change to your home and the look of the neighborhood. Because this work requires the knowledge of structural elements and how to retrofit the new part of the house to the old portion — while battling the time constraints of the harsh elements — it’s best that this portion be done by someone with experience. The contractor will frame the shell of your home, leaving the interior open for the utilities in the next phase to be installed. You can either leave the rest to the professionals or project manage it at your own pace.

Internal Systems

The second stage of a home addition focuses on all the internal systems, including plumbing systems, electrical systems, heating and cooling systems and energy systems (insulation). These are the systems that function to control your water, light, air, and their efficiency that you use daily. 

There are a lot of different options for plumbing, so it’s important to have the guidance of a knowledgeable designer that is familiar with the fixtures that are available on the market. The plumbing contractor should be able to work with the design and install the rough plumbing to accommodate the fixtures that you have picked out. The plumber will also install any gas lines that will be needed for heating systems, hot water heaters or cooking in the kitchen. You may also want a gas line run to the exterior for a grill. Regardless of what is being run, the plumber will have to calculate the volume of gas that the appliances need to operate and size them accordingly.

Your electrical system requires a lighting plan that is typically provided with the architectural plans. By the time it comes to install the rough wiring, most homeowners want to change the lighting around or add outlets, data-wire, or cable to the plan. This isn’t a problem at all, and your electrician should be able to help you with that while they install the wires. You might have to upgrade your panel if you add too many wires so check with your electrician if your panel is adequate. 

Renovating your home is a great opportunity to cut energy costs and boost your home’s value. Heating and cooling go hand in hand with its energy efficiency as well. When it comes to making your home more energy-efficient and lowering your energy bills, it’s best to focus on the four basics: insulation, air sealing, heating and cooling systems, and energy-efficient window upgrades. While everything is open, consider investing in a high efficiency direct-vent system or spray foam insulation.

Each respective system will have inspections when completed to ensure that it complies with all structural, safety, and energy compliance codes. This is to ensure that all of the components of the system are working correctly, without leaks or other issues. If there are any issues or concerns, address them at this time before the walls are closed up from the inside.

Interior Carpentry

The third stage in the home renovation process is the interior carpentry. This is the stage where you begin to see the interior surfaces of your home take shape and you can start to imagine how it will look when it’s finished. This is the point where you’re going to see some real progress at the interior of the project as the actual living space is partitioned with the ceiling, walls, and floor surfaces, and finished with paint, floor finishing and tiling.

Some of the work that you might not want to do yourself is hanging drywall, floor installation, fabricating stairs, door and moulding installation, tile installation, and rolling out the different layers of paint. A lot of that is very labor intensive and requires more than one person to complete. Each of those specialty trades also requires special equipment to perform the work, so it’s something to keep in mind when reaching this stage. If you use a general contractor, they’ll handle everything from job site clean-up to material ordering, to coordination and oversight of these trades. 

Termination and Installations

The fourth phase is the installation of the cabinets, vanities, backsplashes, medicine chests, closet organizers, trims, door hardware, cover-plates, vent covers, appliances, lighting fixtures, as well as termination of the internal systems that were roughed-in prior by the electrician, plumber, and HVAC contractor.

Most of the items that are installed at this last phase of the project are usually homeowner specific items. After everything is installed, the contractor will test all systems to ensure that they are all functioning. This is when all minor adjustments are made to finalize and complete the project.

In this stage, the carpenter on the project will also address any punch list work and whatever touch-ups or repairs that need to be done. If a contractor is hired to oversee this portion of the project, then several walkthroughs will be done to make sure the end results satisfy the homeowner. 

Closing Advice

We understand that to some, this process may seem self-explanatory and simple, but for others, the 4 basic stages of a home addition project may be arcane. It’s important as a homeowner to know exactly what your project comprises as this allows expectations to be set before building starts so there're no surprises throughout the rest of the process. Whether you’re hiring a general contractor for the entire project or Doing-It-Yourself at your own pace, understanding these four stages will ensure a higher chance of a having a smooth and successful home addition project.

While you can do all these stages without hiring a contractor, we recommend at least having the shell (which we can do for Bergen County, NJ homeowners)done by a professional.

Regardless of what you choose to do, we hope breaking down these four steps will make your upcoming home addition project go as smoothly as possible. Happy building!

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