Growing herbs and spices in your backyard are rather easy, but when you need to grow vegetation that needs a controlled climate environment, you would need a greenhouse in your backyard. A greenhouse is paramount when you opt for horticulture or need to grow plants that are not native to your area.
A greenhouse is a great addition to your property if you are more into gardening and need to grow specific vegetation, flowers, and fruit-bearing trees that need special care. It’s a room where nature takes care of itself, and you just have to maintain the environment and the structures.
The actual cost of setting up a greenhouse will largely depend on the dimensions, materials, hardware installation and other factors. However, in average, the cost of building a professional greenhouse would vary between $4000 to up to $23,000 depending on the size of the construction.
Cost of a Greenhouse Depending on its Size
Basic (avg. $500)
For a beginner, building a greenhouse is fairly inexpensive, especially if you can build it yourself. An arced greenhouse of 6 sq.ft is a decent size to grow your favorite fruits and flowers. With just over $500, you will get all the kit to build a basic, small greenhouse all by yourself. However, with just $500, you will not get any plumbing or electrical fixture, and the covering would make a kind of polyethylene plastic instead of glass.
Medium (avg. $4000 to $7000)
If you are a dedicated grower of your garden, you will need an average of 12 sq.ft. Greenhouse. These types of semi-professional greenhouse cost more and require foundation, flooring, plumbing and installing electrical systems. These structures should be done by professional, and the siding is typically made of polycarbonate or glass. These greenhouse structures will also have a vented roof for humidity control.
Professional (avg. $12,000 to $25,000)
A professional greenhouse cost an avg. $27 per square foot. For an average budget of $12,000 to $25,000, you will have a large greenhouse of up to 1000 square feet. At this price range, your greenhouse will have all the features you will even need, including an HVAC system for temperature and humidity control. This system will also have automated computer controlled sensors that operate vents and windows without human intervention. The greenhouse structure will also have an automated watering system, feeder, lighting, and drainage system. However, you can guess that the greenhouse needs professional installation, which is going to cost your extra.
Material Cost for Siding
The biggest expense in constructing a greenhouse is in the siding. You have the option to choose from inexpensive polyethylene to polycarbonate and tempered glass. Each siding material has its advantages and downsides.
Here are some common greenhouse covering materials
Glass (avg. $500 to $3700)
All traditional greenhouses had glass covering for siding. But, now people are moving towards polycarbonate and polyethylene for hobby greenhouse construction. Glass siding is expensive to install, and maintain, but it is also more durable and can last up to 30 years. Glass is still the most preferred material by professionals.
Even for a small 5×10 feet construction, you will have to cover up to 150 square feet of surface with glass covering. Glasses come in annealed and tempered glass variant which can cost on average between $6 to $9 per square foot. So, for a small installation glass siding alone will cost between $500 to $1200 on average.
For a medium size hobby greenhouse, the cost of glass siding installation alone will cost between $1500 to $3700 on average. This cost doesn’t include clamps, fasteners and other strips needed to keep the siding in place, which suggests that glass is an expensive siding material.
Polycarbonate (avg. $200 to $1600)
Polycarbonate is probably the most popular choice among today’s greenhouse professionals. It’s strong, light-weight and comes to UV treated to prevent yellowing and deterioration. PC siding also has a high lifetime of up to 10 years with little maintenance. Polycarbonate provides a wide range of option to choose from, both in material and thickness.
- Corrugated PC rigid panels with a single wall construction cost an average of $5 per linear foot.
- PC rigid panels (4×8 foot) with a twin wall construction cost an average of $50 with 6mm thickness.
- Rigid panels (4×8 foot) with a triple wall construction cost an average of $120 with 16mm thickness.
- PC rolls with twin wall construction with a layer of air space cost nearly $7 per linear foot.
Depending on the type of Polycarbonate siding, the average cost of installation can vary between $200 to $1600 for a typical 10 square feet greenhouse.
Acrylic (avg. $550 to $1600)
Acrylic is a stronger alternative for siding, which can withstand rough weather conditions including snow and hail impacts. That said, it demands special frames and fixtures for its thermal expansion and contraction in varying temperatures. Acrylic is expensive to install, but it is cost-effective in the long run which can last up to 20 years and cut down the heating cost to 25%.
- Corrugated clear single-layer acrylic panel costs up to $90 for a 3×8 foot panel.
- Twin acrylic panels (8mm thick) can cost up to $110 for a 4×8 foot panel.
You could also purchase triple acrylic panels, quad acrylic panels which provide the most insulation. Further, you have the option to purchase non-drip acrylic panels and UV blocking acrylic panels for special vegetation needs.
For a small 10 square foot hobby greenhouse, installing acrylic panels can cost up to $1600, and for smaller A-Frame construction, it would cost approx. $550.
Polyethylene (avg. $20 to $150)
Polyethylene or plastic can be a good option if you are looking for a cost-effective installation. Plastic doesn’t necessarily mean it is inefficient as there are specific greenhouse polyethylene films available for this purpose. That said, though polyethylene films are cheaper, it doesn’t last longer, and you will have to replace it season after season.
- Utility grade polyethylene film cost just about $20 for a roll, but it lasts only for one season.
- UV protected films prevent more sun damage and would last for up to 3 years at the cost of approx. $40 for a roll.
- The thermally protected film reflects most of the IR into the greenhouse which will reduce the heating cost to up to 25%. These films are also able to maintain high temperature at night, making it a more efficient option. Thermally protected films cost nearly $100 for 55 feet sheet.
- Polyethylene covering with anti-condensation film can reduce dipping and harsh sunlight. The opaque films cost around approx. $120 for a 55 feet film and can cut down light transmission to 50%.
For a small A-frame greenhouse, polyethylene film will cost avg. $15 per year and avg. $12 per year for a UV protected film. Thermal rolls will cost you an avg. $11 per year for a small A-frame greenhouse. For a 10-foot hobby greenhouse, polyethylene film can cost nearly $110.
Polyethylene Panel (avg. $200 to $850)
Some polyethylene plastics are made into panel instead of sheets with a twin wall construction for insulation. These panels are semi-flexible and can be installed to shallow arches.
- UV protected 3 mm rolls cost an avg. $6 per foot
- UV protected 5 mm rolls cost an avg. $9 per foot
For a small 10 foot A-frame greenhouse, it would cost between avg. $200 to $300 and for a small hobby greenhouse polyethylene panels can cost between avg. $610 to $850.
Fiberglass (avg. $350 to $1000)
Fiberglass is a clear siding material and sometimes translucent that allow more light at low angles. You will also find these panels with ten years guarantee from top manufacturers against yellowing and breakage. However, conventionally fiberglass panels deteriorate faster and trap dirt which needs regular washing.
- Rigid fiberglass cost nearly $80 for an 8 feet panel
- Flexible fiberglass rolls cost up to $350 for a 50 feet roll
- For a small A-frame greenhouse, you would need over six fiberglass panels which can cost up to approx. $350.
- For a hobby greenhouse of 10 foot, you will need up to 15 fiberglass panels which can cost up to approx. $1000.
Vinyl (avg. $150 to $280)
Vinyl is typically used for showrooms because it is a clear material. It is not a good choice for covering but can be used on the ends so that you can have a clear view of the greenhouse. These clear siding cost between approx. $150 to $280 for a roll.
Pros and Cons of Each Siding Material
- Aesthetically beautiful
- High thermal conduction
- Lasts longer and doesn’t have to be replaced unless broken
- Concentrates light, which could burn out some plants
- Glasses are heavy and requires stronger and expensive frames
- Flexible to fit all shapes and sizes
- Cheaper than any other siding material
- Needs frequent replacement and additional care because it is prone to damage.
- Provides better light diffusion
- Lightweight and strong
- Can break in harsh weather condition
- Expensive to install
- Lightweight and high insulation
- Doesn’t need heavy and expensive framing
- UV treated panel are less prone to deterioration
- Wears-out easily
- Cannot be cut to fit any size of greenhouse
- Repairs and replacement can be expensive
Greenhouse Framing Cost
Wood (avg. $2 per linear foot)
Cedar is the most cost-effective and durable wood framing option for outdoor installation. Wooden frames are easy to customize and give a natural look to your greenhouse. In an average wooden frame cost around $2 per linear foot.
- Looks aesthetically stunning and are durable
- It has natural thermal insulation properties
- Easy to customize and give the desired shape to your greenhouse
- Needs frequent maintenance
- Wooden frames are prone to termites and insects
- Treated wood has to be shielded
Steel (avg. $3 per linear foot)
Steel frames are stronger but are harder to work with; they are also twice as expensive as wooden frames. In an average steel frames cost nearly $3 per linear foot.
- Durable and strong enough to withstand harsh weather conditions
- Requires little maintenance
- Difficult to cut and assemble for complicated designs
- Lower thermal insulation
Cost of Greenhouse Site Preparation (avg. $600)
For the most part, building a greenhouse would require leveling of floor; although some leave its natural soil, it does get messy in the long run. Concrete flooring would cost nearly $10 per square foot, which include texturing and draining system. For pavers, it would cost you approx. $12 per square foot and for gravel it would cost you nearly $3 per square foot. Labor cost for construction can go up to approx. $550.
Greenhouse Equipment Cost (avg. $2000 to $7000)
For temperature and humidity control you can manage it manually for a smaller A-frame greenhouse, but larger constructions would need other equipment including HVAC and lighting system. For a larger greenhouse, homeowners should expect to spend up to $7000 for the HVAC system and lighting including labor cost. Most lights cost between approx. $30 to $120 each and HVAC system can cost from $150 for a simple and portable system to over $2000 for a professional setup. Building a greenhouse also require a permit in most location, for which you should check up with your local offices.
Cost of Greenhouse Kits (avg. $300 to $11,000)
Instead of building a greenhouse on your own, you could simply buy greenhouse kits, which come Pre-fabricated. Greenhouse kits are especially suitable for homeowners who are a hobbyist. For professionals, it is advisable to build a greenhouse from scratch, although they may purchase larger greenhouse kits and upgrade it to their needs.
A 4×4 ft polycarbonate greenhouse kit will cost approx. $300. For a 14×19 ft, larger greenhouse kit can cost approx. $11,000. Small herb-garden wooden greenhouse can cost as little as approx. $150. Other amenities such as storage and potting benches can cost up to approx. $2100. Heating equipment will cost additional approx. $250 for a standard greenhouse construction.
For most homeowners in the US, they need a small size greenhouse for a hobby, which they can build on their own. It can be accomplished at just under $1500 including all expense with DIY installation.
- You could look for upcycling old materials such as metal and wood for framing and plastic containers for pots. Upcycling materials is a true hobby and give you enough satisfaction in your work.
- While building your greenhouse, consider your local climate condition such as if you live a relatively colder area, you will need thermal insulation. For a warmer area, you will need shades; whereas most would need both to accommodate all seasons.
- Next important aspect in a greenhouse is drainage, air circulation, and pest control. You will have to make an additional effort for wooden frames.
- If you are planning to use lighter frames, you should use polyethylene for covering. If you are planning to use glass, you will need much stronger frames.
- The greenhouse is rather flimsy than usual concrete buildings and therefore are prone to damage in high winds. It is therefore advisable to anchor your greenhouse on a secure concrete floor.
- For a full set up you could upgrade your greenhouse over time instead of spending everything at once.
Greenhouse an addition to your property, especially if you want to grow your vegetation or want a flower garden. However, it is something that needs constant care from your end, and of course, it’s a hobby so it should be alright with you. To be honest, you can have a little greenhouse for as little as $300 and can stretch it up to as high as $25,000 if you have that kind of space and want to generate revenue out of it. Then again, you should first acquire knowledge of the type of vegetation and flower plants you can grow in a particular season, and for more exotic plant varieties, you will have to spend extra on amenities and climate control equipment.