When investing in a greenhouse a common question that comes up is permitting. Your local building codes will determine which permit requirements your greenhouse will need or not need. If your local building official office has been affected by budget cuts anticipate the enforcement of building codes that had previously been exempted. Previously, growers needed to be concerned with the impact of snow loads and wind resistance on their greenhouse. Now, some states have code requirements that call for a hoophouse to have an engineers seal that certifies that the temporary structure meets all the code standards, including that the foundation posts are set in concrete. You will need to find out what is required for a permit from your local building official, because they are still allowed considerable discretion.
The following is a step by step guide and tips to getting a permit for your greenhouse.
Step One: Call first and be prepared that you may be required to give your job site address, the type of ag structure and if you’ll be using electricity. Here’s a tip on how to get the information you need and remain anonymous.
“Hello Building Dept. I am zoned ag. and considering putting up a non code temporary ag. structure that does not require footings or a slab. Is that ok?”
Step 2: Make an appointment to meet with local enforcement to discuss the requirements needed for starting your greenhouse project: maps, plans and calculations. This step will be the most efficient use of your time and resources, especially if you discover your greenhouse project only requires a hand drawn sketch instead of sealed drawings.
Step 3: Several signatures are required before the building official can sign a permit. The building official will help you find out if your community has zoning. If so, the zoning officer usually requires a plot plan that shows the location of the greenhouse with relation to property boundaries and other structures. This plan should show setbacks from the property lines and separating distances.
Step 4: If your greenhouse will be built near wetlands then most communities have a wetlands commission. The wetlands officer will want to know how you plan to control runoff, what sedimentation and erosion control measures will be installed and what pesticides you will store and use.
Step 5: Remember to ask if you’ll need additional permits for a new driveway entrance and restrooms.
Step 6: Licensed electricians, HVAC and plumbers are required in most states. Your building permit will more than likely require the license number and name of the professional to be listed.
Step 7: Do your due diligence when selecting a greenhouse company or erector. Ask other growers in the area who has a good reputation for quality and dependable work. You can find our customer testimonials on www.ForeverFlowering.net
Step 8: In many states the design and specifications are your responsibility and will require the seal of a local licensed architect or engineer. The building official’s responsibility is to make sure your greenhouse meets local code requirements.
Step 9: If you have an existing greenhouse that needs structural changes or you need to demo an old structure, you’ll also need a building permit. Adjustment will be made to you tax assessment only after a copy of the permit is forwarded to the local assessor. The most expensive mistake you can make is not getting a building permit. If you’re unpermitted greenhouse is discovered, you may be required to remove the structure. You’ll find that building officials are there to help make the permit process as easy as possible. Like you, they want to ensure that your greenhouse is a safe place for your employees, customers and you.
Here is a list of common building mistakes:
Grading Permit: After you receive your permits, the first step is clearing the land and grading a level plot. Follow drainage and proper erosion controls closely. One of the most common mistakes when prepping the pad is putting down gravel first.
The right way is as follows:
Dig and Trench: Water lines, power, propane etc. The pad should be laser leveled within an inch variance, if possible. A 4 foot difference in elevation from one end of the pad to the other does not qualify as level.
Holes: Once the pad is cut, leveled and compacted we can set the strings and mark the holes. The holes are augured with a 12-18-24″ bit depending on the structure. Its easiest to have a concrete truck drive right onto the pad and fill the holes with the chute off the back. Once the mud sets and is dry we can call in the gravel.
Gravel: One of the most common mistakes in prepping the pad is putting down gravel first. Gravel will ultimately get contaminated with soil when you dig through it, so save this step for after you’ve completed the above steps. I like to use 3/4 crushed base rock. The same stuff you see on driveways. It has small fines mixed in the rock so its easy to compact. Washed rock does not compact well and will end up feeling like loose marbles when you walk on it. The end wall columns on Forever Flowerings greenhouses are 10′ apart, so a dump truck can barely fit inside to dump right on the pad. I typically spread a 6 inch layer of gravel throughout the greenhouse. It’s also a good idea to keep moisture in the rock and compact it. In some cases, you can get the gravel to be compacted and smooth like concrete.
Erosion Permit: If you do need a permit, the county will tell you everything you need to know. One hurdle I see as a challenge is the regulators and licensing authorities for cannabis want everything to be permitted, but if the building dept. doesn’t require one then how can the licensing authorities for the crop require one? I believe its a confusion or interpretation problem that arises from licensing indoor operations. The 2 cannot be mixed, joined or compared for licensing and permitting issues.
Erosion Control: Straw is one of the easiest and most affordable ways to repair the land. I like to spread straw over the areas of land that were disturbed. Grass seed, filter fence or straw waddles might be required for cut and fill slopes to avoid sediment run off and landslide protection.
John W. Bartok, Jr., Extension Professor Emeritus & Agricultural
Engineer, Department of Natural Resources and the Environment,
University of Connecticut, Storrs CT – 2013