I get this question a lot. What is the difference between a glass greenhouse and a polycarbonate greenhouse. I am going to assume that the frames are basically the same, so the biggest difference will be in the glazing material.
Glass greenhouses will be more expensive than a polycarbonate greenhouse. Especially with a curved eave. The glass is all tempered (safety) glass, even the curve. The curved tempered glass is more expensive than doing a curved polycarbonate. The twinwall polycarbonate is flexible enough that it is bent right onsite as you are installing the kit. There are no special tools or processes needed to do this. You just simply bend it over into the curved frame and attach it.
Looks are another obvious difference. The glass greenhouse will have more of a timeless look to it. I suppose if you want to use the word “fancier” that could even be applied. Just in looks, not in function. A lot of people don’t like the polycarbonate glazed greenhouse as it will be translucent rather than transparent. It will not be like looking through a window like the glass greenhouse will. Twinwall polycarbonate is made up of 2 sheets, an interior and an exterior. These sheets are both clear and would look much like looking through a window if you peeled the walls apart. Multiwall polycarbonate is much like looking down the end of a cardboard box. You will have the exterior and the interior sheet with a rib in between them. The rib will run straight between the 2 sheets, not curvy like in a cardboard box. This rib is what distorts your view. You can see color in a polycarbonate greenhouse, just not a clear form.
The glass greenhouse will not be as well insulated as the polycarbonate greenhouse. A single glass greenhouse will have an R value of approximately 0.95. A 6mm twinwall polycarbonate greenhouse will have an R value of around 1.6. This means that if you have the same size single glass greenhouse and polycarbonate greenhouse in the same location, trying to heat it to the same temperature, the glass greenhouse will cost you more to heat. It seems from the difference in the R value that it would be about twice as much. That is not the case. There is a formula that uses the size of the greenhouse, the difference in the temperature inside and outside the greenhouse, and the glazing material. If this is a consideration in your instance, the best way to determine how many BTU’s you will need is to actually do the calculations.
Breakage is another issue. Tempered glass will break if it is hit in the right manner. There is just no way around it. But, it is tougher than regular float glass, and it will shatter into small pieces, so safety is not a concern. Polycarbonate has a 10 year warranty against hail damage. It is a very tough material. It will not break like the glass.
Lifetime of the glazing material is the last issue I will discuss. Glass will pretty much last forever unless it is broken. Polycarbonate generally has a warranty that the light transmission will not vary more than a specified number in 10 years. This is just a fancy way of saying that it will not turn yellow or get brittle. Some of the manufacturers have extended their warranties to 15 and even 20 years. I have personally seen sheets that were 15 years old and still in use. They looked just fine. I have had reports back of 20 year lifetime on the material.
Glass greenhouses vs polycarbonate greenhouses? What is the conclusion. They both have their benefits, it just depends on which fits best into your needs. The best decision is to make sure to get a greenhouse, no matter what type. It will give you hours of enjoyment, produce food for your family, protect your orchids, and be the envy of your friends and neighbors.
Getting ready to heat your greenhouse? Well, now is the time to either check your existing heater or to purchase a new one. Our top pick, the Southern Burner natural gas or propane greenhouse heater is going to have a price increase (the first time since 2008) on November 20th. So you want to be sure to order prior to that date. This is a super greenhouse heater that will fit under a bench and not take up any valuable floor space. It requires no electricity. The heater is all aluminum and stainless steel. They will keep the temperature at the top of the greenhouse within about 5 to 7 degrees of the floor heat. There is a vented and a non vented model available. The vented model is 25,000 BTu’s and will be adequate to heat most small hobby greenhouses. If you have a larger greenhouse you would simply add a heater or two. There is a formula to calculate how many BTu’s will be required to heat your greenhouse based on the size of your hothouse, the glazing type, the indoor and outdoor temperatures. Please be sure to follow this formula, or your heater may be too small to get your greenhouse to the desired indoor temperature. Plan ahead. Winter is headed our way. Don’t be left out in the cold this year!
You have dreamed for years about owning a greenhouse. Now the time has come. What size do you get? Most people have problems making this decision. I think the best way to start is to think about how you are going to use the greenhouse. If you have plants that you are going to overwinter, I suggest laying them out in your yard in a configuration similar to what you will do in your greenhouse. Then you just measure outside the plants and voila, you have the answer to this question. If you are growing in raised beds, decide what size beds you will have and draw them out on a piece of paper allowing for adequate walkways. The same would apply if you are using systems such as hydroponic systems. Find out their size and draw them in a configuration you like on a piece of paper. When considering raised beds and/or greenhouse staging, you need to be sure that they are not so wide that you are unable to maintain the outside plants properly. I suggest not using any wider than a 3′ bench for benching that will be against a wall. If you are using a bench in the center aisle, it is OK to use a 4′ wide bench. Keep in mind that most of us will be comfortable with a 3′ wide walkway, so be sure to draw them in as well. I do not recommend even trying to put a center bench in a 12′ greenhouse. Lots of people try and I don’t think they are too happy with the outcome. If I would do this, I would only use 2′ wide benches to ensure adequate walkways. I would get at least a 16′ width for a center bench. The best thing to remember is that we are all collectors. You know, that perfect color plant, an unusual vegetable, etc. Don’t buy a greenhouse you will be crammed into with your current plants. Always allow a little room for expansion. If you need any help with this decision, feel free to contact us at Advance Greenhouses.
So, You have decided you are going to get a greenhouse. Congratulations. You will love it. Now the first question, of many, is what is the ideal size for a beginning greenhouse. There are a few things to keep in mind as you start to look. You will probably want to go at least a little larger than the size you originally decide on. After all, we are all collectors. We just found the next perfect orchid to add to our collection. Or, there is a new seed that we want to try in the garden. So, we will be starting more plants than originally calculated. If you are overwintering plants in your greenhouse, you know that you cannot resist that specimen with your favorite color or flower.
Which Size Greenhouse is Perfect For A Start?
If you have plants already, the easy way is to set them out in your backyard in a configuration like you would use in your greenhouse. Don’t forget to allow an aisle. Then just use surveyor stakes and mark out the size of the greenhouse. If you are going to have plants on benches, figure out the size of benches you will be using and then draw them out in a graph to see what size you need. With benches, we do not recommend going over 36″ deep. This is about all you can reach over and comfortably work on your plants. If you think you want a center aisle, I would go with at least a 16 foot width. That way you have room for your benches and a nice walkway on either side. Greenhouses are available in many sizes and configurations. We are always here to help. Do not hesitate to contact us with any questions. Start here to find your perfect greenhouse.
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