How to Build a Polycarbonate Greenhouse

Want to know how to build a polycarbonate greenhouse? Having a kitchen garden in the backyard is what we can think of if we want o use fresh veggies. If you are fond of pretty flowers, how amazing it will be if you can have them at your own home. But growing vegetables or plants intended for medicinal purpose or just to add delight with ornamental plants and pretty flowers need proper care and maintenance too. A greenhouse is a perfect thing to think of if you want to do gardening.

Since multiple options for greenhouse materials are available including glass, varied kinds of plastics, fibreglass, acrylic, we will have to make a choice of the material. One such option that is very efficient and light on the pocket is the polycarbonate. It has other advantages too like that of being lightweight, having better insulation and retention properties. Even lesser heat tends to loose from the greenhouse fabricated using polycarbonate. You can do it yourself. Yes, you can make your own greenhouse that suits your size and pocket. And you will enjoy while you make it because the outcome will be much pretty.

So, let us start with this interesting craft and fabricate a greenhouse.

June 13, 2024

Materials Needed

  • Measuring tape
  • Carpenter’s Square
  • Polycarbonate sheets
  • Drill driver
  • Screwdriver
  • Spirit level
  • Wooden sleepers
  • Batten screws
  • Mechanical saw
  • Fine-toothed blade
  • Hand Shear
  • Markers
  • Glazing tape

Step by Step Instructions

  1. Choose the location:

You may want the greenhouse in your home backyard or in the garden or on the rooftop if you are planning for terrace-farming. The ideal location would be based on the direction of the sunlight. Try to choose a position where the greenhouse can get plenty of sunlight from one direction in the morning and from the other direction by sunset. Still, the choice can be done according to the space available too.

  1. Mark the chosen site and prepare it:

Mark the chosen site using a paint. You may use a carpenter’s square for more accuracy. Drain the floor well to create a level area.

  1. Making trenches and positioning bearers:

Mark three locations parallel to each other. Locate the bearers and dig trenches. Now, make three bearers using the sleepers. Lay the end of the length to end and secure them with batten screws. Before that, make sure that the sleepers are properly aligned.

Now position the bearers on the marked site in a parallel position. Use a spirit level to check if the level is proper or not. In case, the spirit level indicates an improper level, use blue metal gravel and add it in the trench. Else wise, you can use sleeper blocks for elevation.

Once the level is fine, position the blocks.

  1. Attaching Sleepers:

Sleepers will have to be positioned across the bearers. Check for the square. Secure the position with the batten screw. Use the screwdriver to do this. Sleepers should be well-aligned one against the other and properly secured.

  1. Preparing the base:

Once the sleepers are attached well, position the base. Assemble them to form the base frame. Tally its diagonal lengths to ensure it is a square.

How to check the base frame?

To check whether the frame is in a perfect square, the lengths are measured in diagonals. Take a measuring tape and measure the length of one end to the other end which is located to it diagonally. Now repeat the measurement for the other two diagonally located corners. Cross check the measurements. The two lengths should be the same. In case there is a variation amongst the two recordings, do necessary adjustments and ensure a square before proceeding further.

  1. Building wall frames:

Build upright wall frames. You can use wood, but aluminium fabrication is a better choice owing to its strength, lightweight and resistance to corrosion. Plenty of other choices are also available and you can choose the best that suits your purpose.

  1. Adding wall panels:

Since we have chosen polycarbonate to be used as our wall panels, we will have to first cut the polycarbonate sheets as per our required lengths. Polycarbonate panels are available as either single-walled, double-walled and triple-walled panels. You may need to choose the one you need for your glasshouse. You can get the panel coated for protection from UV light. If you do not get polycarbonate readymade panels, you can easily fabricate them on your own.

To cut out the polycarbonate sheets to create wall panels, fix the sheet on a flat saw table. Measure and mark the cut. Install the fine-toothed blade in the saw. The settings of the saw blade are done in accordance with the type of the desired cut. And the speed of the saw is also adjusted in accordance. Now, while moving the sheet into the saw, do not stop in between before the cut is made. Otherwise, the sheet might crack. Once the wall panels are cut in desired lengths and shapes, they have to be installed in the frames.

Install the panels. Being light in weight, it is easy to install polycarbonate panels in the frames. Leave one side panel for the louvre window.

Cap the panel end to avoid moisture getting built-up. And also seal the joints with the help of glazing tape.

Since the polycarbonate when subject to temperature variations can expand or contract, drill the fastener holes larger in size as compared to the fasteners themselves.

  1. Checking the perfect square:

Use a carpenter’s square to check whether it is in a perfect square. It is rare that it will not be square, but still, if it is not so, you can try repositioning.

  1. Securing the floor:

Once the greenhouse is in position, you will need to fix it to the ground. Secure the base with batten screws.

  1. Roof installation:

Before installing the roof, make sure to include a window or a vent. Assemble the roof panels. Keep in mind the cross-ventilation and the air flow.

  1. Beautify:

Once your greenhouse is ready, you can make racks inside, keep benches to keep the gardening tools and other necessary items. You can beautify your glasshouse as much creatively as you like.

How to Cut a Polycarbonate Sheet

Polycarbonate sheets are strong, tough corrugated and lightweight thermoplastic sheets having wide applications in various industries. They are highly resistant to heat and electricity.

Without getting them broken, they can be molded or formed and deformed easily.

Why would you need to cut a polycarbonate sheet?

Polycarbonate sheets are widely used in the construction of noise barrier walls, glazing, dome lights, etc. since they can provide insulation from electricity and sound. Protective windshields, corrective lenses, medical equipment, bottles for liquids, optical disks, lightweight cases for luggage, electronic items like toys, computer cases also find the usage of polycarbonate sheets. Durable and lightweight items can be made using polycarbonate sheets. Knowing how to cut polycarbonate sheets will let you make durable creative and innovative things with ease.

So, one in the construction industry or using it to doing it yourself (DIY) self crafting purposes may need to cut a polycarbonate sheet to be able to put it to utilization.

We will now learn how to do them so. Polycarbonate sheets come in a varied range of thickness. Depending upon the same, materials and methods used as the cutting tools may vary.

Materials needed to cut a polycarbonate sheet:

  • Hand shears
  • Mechanical saw (circular saw, vertical band saw, hand-held jigsaw)
  • fine-toothed blade
  • Duct tape
  • Marker
  • Measuring tape
  • Sharp utility knife
  • C-clamps

Step by step method to cut a thin polycarbonate sheet:

  1. Paper thin polycarbonate sheets can be cut in a jiffy.
  • Fix the sheet onto the flat surface using duct tape. The sheet should not be stretched. It can alter the line of cut.
  • Measure the cut and mark it clearly with the marker.
  • Outline the cut using duct tape.
  • Since the sheet is paper thin, you can cut it with a sharp utility knife easily. Now, you have the desired cut out from the sheet.
  1. If the sheet you desire to cut is a bit thick but less than 0.125 inches equivalent to 0.3175 cm, you may need a hand shear to cut the sheet.
  • The protective plastic cover of the sheet should not be tampered with. This is necessary to protect the sheet from any mechanical damage that may occur to the sheet while cutting.
  • Fix the sheet onto a flat surface using 2 x 4s to provide it support on both sides of the cut.
  • Identify, measure and mark the cuts clearly using a marker. Mark edges on both the sides for straight cuts. Then join the marks with a small straight line.
  • For the straight cut, a circular saw is used. Install the fine-toothed saw blade in the saw. The approximate speed of the saw should be 3400 RPM. If the diameter of the blade is between 10 to 14 inches, it should be in the range of 60 to 80 teeth.
  • Initiate the saw and cut it. Do not stop the saw in the middle of the action or until the cut is finished. The blade will do its work. You need not force the saw. It may crack the sheet.
  1. If curved cuts are desired in the sheet, you will need the hand-held jig saw.
  • Fix the sheet onto the flat surface in a similar manner as discussed above using 2 x 4s for supporting the sheet.
  • Identify, measure and mark the cut areas on the sheet.
  • Install the fine-toothed blade in the saw in a manner so as to have a minimum of 10 teeth per inch.
  • The saw speed should be adjusted at 12000 strokes in a minute.
  • Initiate the saw and cut it. Remember not to stop the saw until the cut is finished. You may not want to crack the sheet.
  1. Curved cuts can also be performed using the vertical band saw. This saw is used for larger sheets, cut on which cannot be performed on a normal small sized saw table.
  • The sheet will need to be supported by the side table supports. Fix the sheet properly and ensure that it is well supported.
  • Identify, measure and mark the desired cuts.
  • Install the fine-toothed blade that has approximately 10 teeth per inch in the saw.
  • Observe the speed of the saw and set it at a rate of not more than 7500 feet per minute. You can use the operation manual instructions for setting the speed.
  • With a vertical band saw, the sheet has to be moved in the blade at a constant speed. Do not push in the sheet too fast. Since the sheet is a thermoplastic, moving in the blade at a faster pace can heat the polycarbonate earlier than required. And this heated resin will melt. The molten fluid can be accumulated in the teeth of the blade and it might break.
  1. For yet thicker polycarbonate sheets, use the circular saw. The thickness of the sheet can be more than 0.125 inches but not more than 0.50 inches.
  2. For performing cuts on the polycarbonate sheets which are thicker than 0.50 inches, i.e. 1.27 cm in thickness, you may use a table saw.
  • Identify, measure and mark the desired cut.
  • You may use a duct-tape to frame the marks.
  • Install the fine-toothed saw blade as per the kind of cut desired.
  • You will have to manually move the sheet into the saw. Remember to keep your speed steady. Neither increase the speed nor decrease it. Keep it constant to avoid the plastic sheet from getting cracked or the saw blade getting broken.
  • Do not stop until the cut is complete.

You may use some light machine oil to lubricate the blades for smooth functioning. Moreover, it is a good tip in the maintenance of the saw blades.

While performing cuts in the polycarbonate sheets, a considerable amount of dust is generated. It is advisable to use the protective gears to avoid inhaling the dust which may be harmful to health.

9 Reasons Why Polycarbonate Greenhouse is Better Than Glass Greenhouse


#1. Light on pocket:

Budget is the most important and the starting factor in initiating any project. So, if your budget is limited, polycarbonate panels will weigh light on your pocket when compared to the rates of glass. Not just the rates of polycarbonate are less than the glass, but also installation cost and the manpower required for polycarbonate panels is lesser than that of glass.

Ease of handling and maintenance of polycarbonate greenhouses saves not just the money but much of your time too which goes in installation, maintenance and repair.

#2. Durable:

Polycarbonate has another advantage of durability over the glass. It does not shatter as does the glass. Unlike glass, polycarbonate panels will not shatter. They can withstand the impact of the normal things a greenhouse can have to face. Hailstones, any heavy flown or thrown objects hitting the windows of the greenhouse. And if you have children playing nearby, it is almost certain you may not want to be complaining about the broken windows with the hard hits from their balls or other likely objects.

#3. Better insulation properties:

One of the main deciding factor to use polycarbonate coverings over the glass for your greenhouse can be the insulating properties of polycarbonate. Polycarbonate walls provide far better insulation to the greenhouse than the regular glass. It retains heat meant to be trapped in more than the glass. So, the average temperature of a polycarbonate greenhouse will be on higher mercury level as compared to that of the glass greenhouse. The plants will stay warmer in polycarbonate greenhouse. Temperature maintenance in seed starting and stem-cuttings is very important. This improves the proficiency and the productivity of the greenhouse.

The thermal efficiency of glass is poor than polycarbonate. So, polycarbonate is a thermally more efficient choice. And the twin layer available in double-walled polycarbonate further enhances the thermal efficiency.

Better heat retention makes polycarbonate greenhouses more efficient. This also extends the time for which seasonal vegetables and fruits become available like any other perennial vegetables or fruits.

If a greenhouse is a part of a commercial set up, year-round availability and higher yield are what you might be looking for. And polycarbonate greenhouses will ensure your profits and that too in a pocket-friendly manner.

Moreover, when the greenhouse is already warm enough, you may not need to install in the heaters, as the case may be with glass greenhouses. It will also save electricity. Again, will save you money.

#4. The longevity of the greenhouse:

The strength of the polycarbonate and its high impact resistance tends to have a longer life than glass greenhouses. Polycarbonate can resist much damage which glass cannot.

#5. Ease of installation and handling:

Owing to its lightweight, polycarbonate walls and roof are much easier to fit in the greenhouse frame. Even a single handler can do this in case of polycarbonate while multiple people are required to install glass panes.

Even handling of polycarbonate is easier than that of glass. Not much care is required while working with polycarbonate. In case replacement of any panel is required, it is much easier to do in case of polycarbonates.

Polycarbonate greenhouses can be made if one wishes to make it on his own using his creativity and a little knowledge. While glass greenhouses require skilled workers to do the job.

#6. . Protection from UV rays:

Polycarbonate walls ensure protection from harmful UV radiations. They filter the harmful rays before the light reaches the plants.

#7. Diffusion of light:

Polycarbonate is plastic and plastics diffuse more light than glass. So, in a polycarbonate greenhouse, the light will be more evenly spread as compared to that from a glass greenhouse. Equal quantum of light received by all the plants will not require you to keep shifting plants from area of more light to the lesser one or the vice versa. While in a glass greenhouse, frequent shifting is necessary to maintain efficiency. Time will also be saved.

#8. Customization options:

Polycarbonate panels are available as single-walled, double-walled or triple-walled panels depending upon the percentage of light retained by them. Double-walled panels retain a higher amount of heat than the single-walled ones. So, even amongst the polycarbonate panels, you have many choices to choose from. While glass panels do not allow such custom offers.

Moreover, polycarbonate panels come in a variety of shapes and sizes and you can choose the one that solves your purpose. Glass greenhouses are mounted on metallic frames while polycarbonate ones generally employ wooden frames. Wooden frames can add up to your style. You may decorate it to add elegance. Creativity has no limitations.

#9. Protection to plants:

Polycarbonate panels protect the plants from the direct scorching sun rays by diffusing it evenly inside the greenhouse. Even the cranny areas of the greenhouse receive an equal amount of sunlight. Glass greenhouses can even burn the plants by overheating.

You have just learned how to build a polycarbonate greenhouse. Having a greenhouse installed is a great idea one can think of. And to make an idea great, it takes in a lot of decision-making. There are so many choices available in the market which further complicates the thing. But a correct analysis of the facts and the features involved can clear the road to our destination. With each choice arises a question and a question always has an answer. We just need to speculate what we need so a better outcome can be generated with the right choices.

Every would-be greenhouse installer will have multiple choices for the multiple things used in the installation process. One such major choice is to decide whether to have the greenhouse made of glass panels or that of polycarbonate. Both are available for glazing a greenhouse. For a better insight into choosing between glass and polycarbonate to be used, we have arrived at 9 amazing advantages of having polycarbonate used over the glass.