How Much Does It Cost To Build A Sunroom From Scratch

Building a sunroom is an excellent idea if you want a space that is connected to the outdoors but is also protected from the elements. There is so much that you can do with a sunroom, including growing plants and creating an indoor-outdoor dining space. With a price tag of anywhere from $10,000 to over $100,000, according to Forbes, you can design this space to be as detailed or as simple as you want.

There are several types of sunrooms that fall into two main categories, three-season sunrooms and four-season sunrooms. A three-season sunroom doesn't include HVAC or insulation, so it isn't usable during the winter months, depending on your location. Alternatively, a four-season sunroom includes HVAC and insulation, so you can use it no matter the weather. A three-season sunroom will cost $80 to $230 per square foot, while a four-season one will cost $200 to $400 per square foot. Regardless of which one you build, it is sure to be a wonderful addition to your home.

Factors for sunroom cost

Lawn Starter breaks down some important factors that influence the overall cost of building a sunroom.

Three Season vs. Four Season

The first factor to consider when building a sunroom is if it will be a three-season or four-season sunroom. This distinction will influence the total price as a four-season sunroom will be more expensive due to the presence of insulation, HVAC, and electricity. A three-season sunroom can cost anywhere from $10,000 to $50,000, while a four-season one can cost upward of $80,000 to build.


The size of your sunroom is another factor that will be reflected in the price. Naturally, larger-sized rooms come with a higher price tag. An 80-square-foot sunroom could cost around $18,000, while a 400-square-foot sunroom will run closer to $90,000. The larger the space, the more materials are needed and, therefore, the higher the price.

Custom vs. Prefabricated

When building a sunroom, you can choose to do a custom-designed space or use a prefabricated kit to build it. A kit will be cheaper than a custom space, costing between $5,000 and $30,000. Labor fees tend to be lower with prefabricated kits as well because they are quicker to build than custom sunrooms. Your options for customization may be limited with a kit, though, so many choose to design the space themselves. 


There are a few options for foundations when you are building a sunroom. For example, you can choose to build upon an already existing patio or deck. That being said, if you are building your sunroom from scratch, you will need a foundation, usually in the form of a concrete slab. Depending on the size of the room, a foundation can cost between $1,000 and $4,800.

Building Materials & Labor

Building materials and labor are huge factors that heavily influence the total cost of a sunroom. Materials may include doors, which can cost from $700 to $7,800; roofing, which can range from $2,200 to $7,800; and windows, which start at $3,200 and run up to $16,000. Labor fees also get added to the total cost and can be anywhere from $4,500 to $17,500.

Additional sunroom costs

As with any project, there are some additional costs associated with building a sunroom, explains Angi.

Interior Finishes

From flooring and paint to hardware and accessories, no space is complete without some interior finishes. Depending on the design of your sunroom, you may spend up to $9,000 on interior finishes, while flooring alone might cost anywhere from $1,500 to $4,300.


Are you picturing a sunroom with a beautiful fan hanging from the ceiling and outlets to plug in all your tech gadgets? This will require electricity, which means you will need to hire an electrician. Electricians charge between $50 and $100, or even higher, per hour. Other costs to consider are outlets, ceiling fans, and light fixtures, which can add up to a few hundred dollars.

Heating & Air Conditioning

If you are building a four-season sunroom, installing an HVAC system is a must. Most people simply add their sunroom to their existing HVAC circuit. Another option is to install a smaller system that is limited to the sunroom. HVAC systems can cost anywhere from $2,300 to $20,500, depending on the size of the room and the type of system you are installing. To save money, some people use space heaters or window air conditioning units.

Types of sunrooms

In addition to the categories of three-season and four-season sunrooms, there are also different types of sunrooms. Home Guide details a few of these models, what makes them unique, and how their prices vary.


A solarium is a sunroom that is fully enclosed in glass, including the walls and ceiling. These spaces provide plenty of light and are a great environment to grow plants indoors. Solariums come with a price tag of $30,000 to $100,000.


Conservatories are typically enclosed entirely in glass, much like a solarium, but are unique in that the roof panels are angled to meet in the center, forming a peak. Including the costs of a foundation, insulation, HVAC, electricity, and glass, a conservatory can cost anywhere from $50,000 to $150,000.

Greenhouse or Garden Room

A greenhouse, or garden room, is the cheapest option for a sunroom and is typically available both as a kit and as a custom build. Some may be made of glass while others are made of polycarbonate, fiberglass, or polyethylene film. Greenhouses cost between $2,000 and $30,000.

Why you need a new sunroom

There are many reasons you may want to install a new sunroom, whether they be aesthetic or functional. Patio Enclosures explains some common motivations for adding a sunroom to a house.

More Functional Space

A great reason to build a sunroom is to add more functional space to your home. Whether you're building a three-season or four-season sunroom, you'll have an additional living space for your family that can be temperature-controlled and used all year round.

Enjoying the Outside While Inside

A sunroom is a convenient way to feel like you're outside without leaving your house. These rooms allow for shade from the sun or a place to soak up some light, depending on where your sunroom is located. The abundant natural light in sunrooms also provides the ideal conditions for growing plants without exposing them to the harsh elements of an outdoor garden.

Protection from Pests

Because your sunroom will have windows, or at least screens, it creates a space that is free from bugs. You won't be bothered by pesky critters when you're in your sunroom, and your plants will also be safe from pests.

Benefits of building a sunroom

Building a sunroom has many benefits, per It adds a beautiful visual element to your home while also boosting your property's total value.

Customization Options

One of the main benefits of building a sunroom is that there are many design options. Not only can you choose from a variety of different types of sunrooms, but there are also loads of ways to customize the space with interior fixtures. You can design the room in the same vein as the rest of your home or create a completely different look and feel.

Increased Home Value

A sunroom increases the value of your home. Consequently, many people recoup the construction expenses when they sell their homes down the road. Sunrooms are also popular with homebuyers, which is another benefit.

Increased Curb Appeal

Sunrooms add to the curb appeal of your home as well. A beautiful sunroom is a stand-out element of your house and draws attention if you are planning to sell.