How to Add a Room Addition to Your House

Homeowners that build a room addition modify their floor plan and construct a space from a new foundation, making it one of the most practical yet expensive and labor-intensive home projects.

Despite the costs and scope, an addition can improve your home's livability and increase its value with extra square footage. But where do you begin? This guide will walk homeowners through adding an addition to their house.

Add an additional room to your home

Photo by Alexandra Gorn

1. Set a Budget and Make a Plan

Room add-ons have grown increasingly popular with the rise of multigenerational households. According to Generations United, one in four Americans live in multigenerational homes, with 57% reporting the COVID-19 pandemic as the primary reason for moving in together. 

With more people under one roof, additions have delivered much-needed breathing room to a cramped space. However, homeowners must set a budget and develop a plan before diving into their projects. 

Homeowners usually spend an average of $48,000 on building a room addition, depending on the size and scope. Looking at other projects can inspire fresh design ideas to help determine an addition that best meets your household's needs. 

2. Find a Contractor

Hiring a reputable contractor is vital to any home renovation and ensures your project goes smoothly. Contractors bring a high level of construction and interior design expertise to create a functional space within your budget. 

At this point, you should've envisioned what you hope to achieve with your addition. A good contractor maintains extensive industry insight to create a detailed design rendering and timeline for completing the project.

Always ensure your contractor holds proper insurance and licensure, has positive reviews and client references and acquires the correct permits for your project. They should also have a list of reputable subcontractors they use for specific tasks like electricity or plumbing.

3. Create a Foundation

Your contractor will lay the foundation to build a room addition. This requires excavating to a sufficient frost depth and pouring a concrete slab. 

Your general contractor will likely hire a subcontractor with specialized skills to oversee this part of the project. 

Homeowners can expect the beginning stages to take a few days or a week to complete. Once the concrete is poured, it needs to settle before workers can frame the addition. 

Framing the space will weatherproof the structure and avoid subsequent delays. Construction workers will install floor joists and raise the exterior walls. The roof rafters and trusses will also go up, and all exteriors will be lined with sheeting materials and roofing shingles.  

Some additions could use modular construction techniques, in which most of the structure is prefabricated off-site, transported, and assembled at the house. Eco-conscious homeowners might prefer this method since it reduces waste and transportation emissions typically found in the construction industry.

4. Install Windows and Doors

Any windows and doors you intend to install in your addition will go in next. Adding them at this stage keeps the structure weathertight and creates another layer of interior protection.

The general contractor or project manager will likely order the windows and doors from a manufacturer and have them shipped to the site, so ordering your selections early is crucial to move the project forward.

Otherwise, you could experience project delays and leave your new room exposed to the elements until the windows are ready to go in. 

5. Rough-in Mechanical Equipment

A room addition will be useless without the most crucial mechanical components like electrical, plumbing, heating, and cooling. 

Before work on your home continues, your general contractor will call numerous subcontractors to install wiring, pipes, and essential ductwork. Because the structure is still in its raw-framed condition, it is much easier for specialized technicians to hide these mechanisms behind the walls and ceilings. 

Although this stage is usually quick, homeowners often wait for an inspector to approve the work before the next leg of the addition begins.

6. Add Insulation and Drywall

Every home needs insulation to stop air leakages and outdoor noise pollution. According to the U.S. Department of Energy (DOE), proper insulation improves energy efficiency and saves homeowners 15% on their heating and cooling bills. 

Subcontractors will install spray foam or batt insulation in the walls, floors, ceilings and roof rafters. The drywall will go up after an inspector approves the work. 

Hanging drywall is a simple enough task that even nonprofessionals can do. It's most important to use large sheets to avoid seams in the wall once completed. When installing drywall yourself, remember to start with the ceiling before installing drywall on the walls. 

7. Finish the Interiors

Contractors can finish the interiors after the drywall is up, including paint, flooring, trim work, cabinetry, built-ins, or anything that fits the addition's intended purpose.

Some interior tasks might be done by the contractor's team or subcontracted to other highly skilled experts.

Supply chain and logistics disruptions have riddled the construction and design industry since the onset of the pandemic. Therefore, making final selections earlier in the process is essential to completing the project on time. 

8. Hook up Final Connections

There's a reason why general contractors subcontract mechanical work to specialized professionals. 

Studies show that electrical incidents cause 30,000 nonfatal shock injuries annually, accounting for 5% of burn unit hospitalizations in the United States. Additionally, 20% of these incidents occur in children. 

Electrical, plumbing, and HVAC professionals will safely finish the final interior work in your addition, such as adding outlets and switches, covers, lighting, and vents. 

9. Restore Curb Appeal

The final step of building a room addition is restoring your home's curb appeal. 

Most likely, your yard will be in disarray after adding a room to your house. Heavy equipment might have ripped up your lawn and garden beds. Your home's siding may have been slightly damaged.

Once the room is complete, you should re-sod the yard and get your landscaping and siding back in tip-top shape.

Build a Room Addition for Space and Comfort

You can build a room addition to add extra space and comfort to your home. If you've found yourself with additional household members or are simply looking for more room to spread out, an addition might be a good project to consider.

Author : Emily Newton