Standard Greenhouse Dimensions Guide

If you have a green thumb, a backyard greenhouse can be a beautiful and productive addition to your home. With a variety of greenhouse sizes and types available, it can be helpful to know standard greenhouse dimensions so you can choose the right greenhouse for your space. Take a look at common greenhouse dimensions and what factors affect greenhouse size. 

What Are Standard Greenhouse Dimensions?

Greenhouses are available in a wide range of sizes and styles, with the average greenhouse size falling between 48 and 80 square feet, or 6-by-8 feet to 8-by-10 feet. Greenhouses can be as small as 5-by-4 feet, with just enough space to walk in, as large as 24-by-10 feet or more for maximum capacity and space for amenities like seating areas. 

Greenhouse Size by Type

Because greenhouses come in such a wide variety of sizes, they can be classed into broad categories by square footage. From extra-small to extra-large, you can find a greenhouse size that fits your needs, available space, and budget.

Extra-Small

An extra-small greenhouse can provide just enough space for beginner gardeners or those with limited backyard space. These greenhouses, which are less than 30 square feet, may have just enough room to step into and space for a limited number of plants. An extra-small greenhouse is a great way to help plants thrive, even if you don’t have much space to put aside.

Small

For those with a little more room to work, a small greenhouse of 30 to 50 square feet offers adequate shelving and space for growing a limited amount of decorative or edible plants. Small greenhouses give you space to step inside and work on your plants, but limit storage space and floor space for larger planters.

Medium

A medium-sized greenhouse of 50 to 120 square feet is a great option for an average-sized backyard with enough space to accommodate it. Medium-sized greenhouses allow you to grow a variety of plants, have a small workspace or bench, and have some room for storage. This size greenhouse can comfortably fit a small vegetable garden as well as a variety of decorative plants.

Large

If you have ample backyard space, a large greenhouse of 120 to 200 square feet allows for a customized design with space for features like irrigation systems, tool storage, seating benches, and more. Avid gardeners can grow a wide variety of plants, including larger types of greenhouse plants and those that need floor space due to their size or weight.

Extra-Large

For a truly luxurious backyard feature, an extra-large greenhouse of more than 200 square feet can fit a full garden, a seating area, and even yoga or relaxation spaces. These greenhouses are a great choice for serious gardeners with backyard space to spare and can be loaded with features like drainage systems, moisture control, automatic windows, and more.

How to Measure a Greenhouse

To determine the ideal footprint for your greenhouse, measure the length and width of the available space and allow for any additional space needed for leveling and a stable base. You’ll also want to take into account sun exposure and accessibility. If you’re considering an attached greenhouse rather than a freestanding one, you’ll also want to measure the available exterior space, keeping building codes and regulations in mind.

Factors That Influence Greenhouse Size

Choosing the right size greenhouse depends on various factors, from the size of your backyard to how you intend to use the space. We break down some of the common factors that influence greenhouse size. 

Backyard Size

How much space you have in your backyard is one of the most important contributing factors to determining the right size greenhouse. You’ll need to decide how much of your backyard you’re willing to allocate for the greenhouse and select an ideal spot that’s level, gets good sun exposure, and can be easily accessed.

Intended Use

Deciding how you’ll use your greenhouse is another key factor in deciding on a greenhouse size. Whatever your greenhouse ideas are, whether you need space to start seedlings to transplant elsewhere in your yard or want to grow a full, lush garden inside the greenhouse itself, knowing your goals for the space can help you select the appropriate size.

Budget

Your budget will also dictate what size greenhouse you choose. A greenhouse costs anywhere from $500 to $16,000 or more, and almost every price point in between. Price is affected not only by size, but what your greenhouse is made of, any additional features like irrigation or moisture control, and prep work to get the site ready for the greenhouse.

Building Codes and Regulations

Some municipalities may have building codes and regulations that limit greenhouse size and location. A local greenhouse pro will know the requirements in your area and can ensure you comply with all local codes. Be sure to learn about applicable regulations and permit requirements before starting. Noncompliant greenhouses can lead to fines, citations, and even having to remove your new greenhouse.

What to Do if You Have the Wrong Size Greenhouse

The wrong size greenhouse can take up too much of your backyard, not give you enough space for your greenhouse’s intended use, or leave you wishing you’d picked another size. Consult with a greenhouse installation pro to cover all your bases when building a greenhouse so you can indulge your green thumb for years.