NGMA Hopes to Block Proposed Greenhouse Energy Regulations

Chris Beytes

Wouldn’t it be great if greenhouses had to meet the same sorts of energy conservation codes as all other buildings?

Of course not! That’s nuts!

Yet that’s what one possible change to the IECC—the International Energy Conservation Code—could mean to someone building a new greenhouse.

Thankfully, the National Greenhouse Manufacturers Association (NGMA) is on the job, watching for possible building code changes that could negatively impact greenhouses and fighting on your behalf. NGMA proposes appropriate changes and clarifications, opposes proposals that have a negative impact on the industry, and provides resources for education and interpretation of the codes.

According to Matt Stuppy, President of greenhouse manufacturer Stuppy, Inc. and a member of NGMA’s Codes and Standards Committee, there are two significant proposed changes to the IECC coming in 2019 that greenhouse owners and operators should know about. One could be good, the other definitely would not be.

“These proposals take opposite view points of greenhouses,” Matt explains. “The first would potentially eliminate energy code regulation of greenhouses, and the second proposal adds more language, removes some greenhouse exemptions, and increases the risk for long-term impacts on the horticulture industry.”

The first proposal, known as CE6-19, is intended to restore the energy code to its original intent of regulating spaces for human comfort and occupancy. This change recognizes that some buildings use energy for industrial, production and specialized processes. Since the majority of greenhouse energy use is for growing and maintaining plants, NGMA believes that greenhouses should be exempted from all, or the majority, of the energy code.

“In the past, NGMA has worked to exempt the thermal envelope (glass, polycarbonate, acrylic, polyethylene coverings) of the greenhouse from the energy code,” says Matt.

NGMA will be supporting CE6-19 since it clarifies and minimizes the role of the energy code as it relates to greenhouses.

The second proposal, known as CE56-19 and proposed by the NW Energy Codes Group, will be opposed by NGMA. This proposal would put significant and impractical regulation on greenhouse operators.

Some of the key problems with the proposal:

• Greenhouses will be grouped with sunrooms and skylights in the energy code.

• The greenhouse exemption for thermal envelopes in the energy code would be removed.

• It would require installation of internal energy curtains on all greenhouses without regard to the purpose and/or growing season for the

• It would require opaque, insulated walls and ends for greenhouses.

• It would create a negative perception that greenhouses are not energy efficient and should be further regulated.

NGMA will oppose CE56-19, because it overreaches on regulating greenhouse energy, and it tries to lump all greenhouses together regardless of their use or purpose.

Detailed information on these codes can be found on the International Code Council’s website:

Like it or not, the energy conservation code will continue to gain adoption throughout the United States, and greenhouse owners will continue to see the effects and requirements of the energy code impact their operations.

Says Matt, “Now is the time to protect the industry and make sure greenhouses are properly understood and the codes are correctly applied to different greenhouse applications.”

To learn more about making your greenhouse energy efficient or to find out more about the NGMA, please visit You can download the NGMA helpful hints on energyconservation at GT