Making a decision to build a commercial glasshouse is only the beginning of actually doing it. There are many other things that you have to consider.
The first and most obvious one is to plan it. What is it that you actually want it to do? Protect against frost? Force plants to flower earlier than they would outside? Provide a hardening-off area? Something else?
Part of your planning should include phoning various builders to get advice. You’ll find that not everyone is happy to help you in this way.
There’s no reason why they shouldn’t, and so those who are reluctant to do so should be weeded from your shortlist.
Those who do make your shortlist should also be willing to travel a reasonable distance to you in order to visit your site.
Of course, this will depend on the job. You can’t expect them to come out for something that could be handled with a few digital pictures and a telephone call; but for a commercial glasshouse, a free site visit ought to be available. If it isn’t, then delete that company from your list as well.
The next step is to design it. Planning is deciding what to do. Designing is determining how it will look.
You need to think about the dimensions that you want. A commercial glasshouse can be small or quite large. Some cover many acres.
There are a variety of styles, but the most effective is the Venlo design. It’s available in normal widths and also what is known as widespan. Widespan is especially good for garden centres because it gives customers a sense of openness. That’s because the visible space isn’t cluttered with the posts used to support the roof.
Height is also a factor. More recently, these structures have increased vertically as well as horizontally. It’s really down to budget; how much you have to spend.
You should also think about whether you want a new glasshouse or one that is secondhand. Both are available and you may have different reasons for wanting either. Make sure that you have a clear idea of the pros and cons of each so that you will make the best choice.
It’s essential that you spend whatever time is necessary with your builder so that you are satisfied that he (or she) knows exactly what you want. This will save you a lot of headaches later on. You’re paying for it, so don’t worry about making a nuisance of yourself.
What to look for in a builder
There are a number of commercial glasshouse builders in the UK, and that means that you’re going to need to find one that meets your needs the best.
What should you look for in a builder?
There are several things, all of which are critical to a successful project.
Skilful and dedicated
Perhaps the most important thing you should look for in a builder is the quality of the workmanship. You want a company that uses highly skilled and dedicated engineers – those who will work only to the highest standard.
How often we still hear of cowboy builders who hang a shingle outside their door and then call themselves engineers. They do more harm than good and usually make a mess in the process. And once they have your money, you never see them again.
This leads to the second thing.
Polite and timely site crew
You also want the people who do the work to be polite and timely.
You have a business to run, and that means that when you need work done you want a site crew that will show up when they’re supposed to and work until the job is finished.
You also want them to be polite, not only to you but also to anyone who comes in contact with them. Anything less than that can leave a bad taste in everyone’s mouth.
Project finished on time and within budget
As a business person, you operate to tight deadlines and with thin margins. Therefore you can’t afford to have a builder disrupt your work by failing to finish a project on time or because of cost overruns. Yet, some builders seem unconcerned about these things – accepting them almost as a matter of course.
Before choosing a builder, you should obtain testimonials from bona fide customers who can verify that the company will give you the product that you want, within the budget you’ve set and the schedule you’ve agreed upon.
Any work that a builder does should also be guaranteed. Builders that hem and haw about this should be eliminated straightaway. Don’t even bother to ask about anything else. Even if they quote for less than everyone else, it could cost you a small fortune in the long term if anything goes wrong and the work isn’t guaranteed.
Heating and ventilation
The means that you use to heat and ventilate your commercial glasshouse will depend on why you’re building it.
If it’s being used solely as a hardening off area, for example, there won’t be any heat. Instead, you may have only some shading material to keep the sun from getting too strong. On the other hand, if your crop is for tender perennials, then you may want to have hot water pipes running around the inside.
Of course the problem with any form of heat is that you could get too much. This is where ceiling windows come in. It’s one more thing that you’ll have to think about.
Thermal shading screens
One way that you could control heat is by using thermal shading screens. These come in a variety of materials and let in everything from a lot of light to none whatsoever. Different weaves also allow disparate amounts of rain to penetrate the fabric.
The screens can be opened and closed either manually or with a computer. The computer method enables you to set it so that when the interior temperature rises or falls more than you would like, it will extend or contract accordingly.
Greenhouse fogging systems
Greenhouse fogging systems are used to control the environment in your glasshouse. They do so by maintaining the internal temperature and humidity. If it gets too warm, then plants can dry out and die; too moist, and it invites fungus. So water is sprayed into the air as a very fine mist that rapidly evaporates, cooling the air, but avoids water on the foliage itself.
Water storage tanks are used to collect rainwater and to recycle the overflow from irrigation. They are covered with black tarpaulin to prevent the formation of algae.
Think of service contracts as having your car serviced automatically.
In the case of your car, there is only one thing that you want and that is for it to start and run perfectly every time you switch on the engine. Anything less than that is a problem.
The same thing is true of your glasshouse. You want to be able to grow your crop without having to think about any of the things that could go wrong inside. That’s not to say that it won’t happen; only that if it is checked and maintained on a regular basis by a company that is paying attention to the age or your equipment and when it was last serviced, then you’re likely to get the most life out of it, and spend less money overall than if you tried to do it all yourself.
I would happily recommend GVZ due to the quality of their work, competitiveness and outstanding service that their team deliver. They always respected our needs and requirements before, during and after construction.
Mark Taylor, Managing Director, Allensmore Nurseries Ltd
We have worked with GVZ for over 15 years and have always found them competitive against other suppliers. For us, the greatest benefit is a real “can do” attitude that exists throughout the team that has solved some of our more challenging projects over the years.
Geoff Parker, Director, Parkers Nurseries
From start to finish the company provided a professional service. The entire team were friendly, helpful and efficient throughout. . . The work has been completed to a high standard and importantly to my satisfaction. I found the company a pleasure to deal with. Every detail was seen through to completion as we had agreed and it was refreshing to be able to trust that a hand shake would be honoured.
Oliver Wass, Olivers Plants