Sunroom Additions: Better Than Conventional Stick-Built Additions?

Luxury sun porch
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Sunroom additions are a fantastically tempting alternative to conventional, full-sized additions.  On average, these light-bathed add-on rooms are, on average, cheaper than stick-built additions.  Because fewer sub-contractors are involved, sunrooms go up fast.  

But are they are viable option to full additions?

The Space Race

It's the oldest story in the world of home remodeling.  You need more space, so you get a few contractor estimates for a regular site-built, stick-built addition (built on a foundation from studs, just like a real house).

 The estimates, all six figures, make your head spin.  

Then you see ads for sunroom additions.  Lots of space, lots of light.  Maybe no bathroom or bedroom space here, but definitely more living-room area.  Low five figures.

Sunroom and stick-built additions share a couple of factors, but mostly this is an apples-and-oranges discussion; these are two entirely different classes of structures.  Let's begin by defining them:

Stick-Built Additions:  Stick-built is the pejorative term for any kind of structure that is built from scratch.  In this case, we are referring to house additions, room additions, and even bump-outs that are constructed from wood, concrete, glass, house sheathing, shingles, and nearly every component that is used when building a home.

Sunrooms:  Sunrooms are sometimes stick-built but most commonly they are constructed of pre-fabricated materials such as steel, aluminum, fiberglass, and glass.

 Pre-fab sunroom additions fit together like a puzzle, though that analogy can be misleading as that implies that they are simple to build by do it yourselfers.  Most of the sizeable sunrooms should be built by qualified technicians.

Differences:  Not an Addition

Because sunroom builders in recent years have been stepping up their game and rewriting some of the rules, these differences are always in flux.

 For example, there was a time when most pre-fab sunrooms were not wired for electricity.  Now, this is a viable option with most sunroom packages.

  1. HVAC:  Sunrooms may not have central heating and cooling (HVAC).  Stick-built additions will usually have at least heating.  If not in the form of central heating, the stick-built addition will have spot heating, such as electric baseboards or fan-driven heaters.
  2. Power:  Not all sunrooms are required to be wired for electricity; all stick-built additions must have power.  
  3. Size:  On the whole, sunrooms have lower square footage cost than regular additions.
  4. Pre-Fab vs. Site-Built:  Sunrooms often come in the form of a pre-fabricated kit that the homeowner can build him/herself.  With site-built additions, as the name says, the addition is constructed on the building site "from scratch" with lumber, concrete, siding materials, etc.
  5. Supplemental:  Main purpose of a sunroom is to provide a supplemental place with generous light for reading, plants, small swimming pools, etc. By supplemental, this is in contrast to a room with necessary functions such as a bathroom, bedroom, kitchen, etc.  Stick-built additions can be anything:  from something an low-function as a reading space to a high-function space like a kitchen or bathroom.

    Misconceptions About Sunrooms

    • No Building Permits Are Needed:  Building permits are required with sunroom additions.  Even the smallest sunroom will require a permit in most communities.
    • Pre-Fab Sunrooms Always Cost Less Than Stick Built Additions:  Not necessarily. Even though sunroom additions cost less per square foot and lack cost-drivers like bathrooms, sunroom builders can easily lard up your purchase with unwanted "extras."
    • "Sunrooms Do Not Need a Foundation. Foundation requirements are as varied as the localities where these codes apply. Generally, you will need a proper building foundation for your site-built sunroom. Pre-fab sunrooms can sometimes be built straight onto existing patio slabs or decks.

    Sunroom Companies

    • Temo Sunrooms:  Beginning in 1967 when founder Nino Vitale, TEMO has been making sunrooms, screenrooms, and patio covers ever since. Now located in Clinton Township, Michigan, TEMO has expanded to basements/additions and pergolas. TEMO sunrooms are installed in 1-2 days.
    • Patio Enclosures:  Based in Macedonia, OH, Patio Enclosures has been making sunrooms since 1966. In addition, the company makes solariums, screen rooms, sunroom blinds and shades, and sunroom furniture.

    Pre-Fab vs. Site-Built Sunrooms

    You can either have a pre-fabricated "greenhouse-type" sunroom addition, which is composed largely of aluminum and glass, or a site-built, "stick" sunroom addition.

    1. Pre-Fab Kits: One type of sunporch is designed and fabricated at an off-site location and is shipped to you flat. In some cases, these "greenhouse" type additions can be assembled by the homeowner. In other cases, it may be advisable for the sunroom retailer to install it for you.
    2. Site-Built: With the site-built "stick" addition, a contractor constructs it just as you would a regular addition or even a house. A foundation is laid, walls are framed, roof trusses built on-site or brought in, and the entire structure is wired for power and may even be plumbed.

    Sunrooms Far Cheaper Than Stick-Built Additions

    SunPorch Structures, Inc., of Westport, CT, is very transparent about the cost of their sunrooms. They produce greenhouse-style sunrooms. With their most current pricing calculator, they indicate:

    • Large: A sunroom of 24 feet long by 15 feet wide is about $19,275. Add about $950 for shipping.
    • Medium: A 15'x15' sunroom costs $14,936, including shipping.
    • Small: A small sunporch addition--about 9 feet long by 15 feet wide--is around $11,170, with shipping running you $700.

    In all scenarios listed above, installation is not included.

    With stick-built additions, the cost regularly exceeds $100,000.  It's difficult to build an addition for less than $50,000.