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Overview

Same superior strength and insulation as our standard Riga line- but now upgraded with a black powder-coated frame and clear plexiglass front, and Victorian cast metal roof cresting! 8 mm twin-wall polycarbonate side walls and 10 mm twin-wall polycarbonate gable ends – all poly is highly break-resistant, long-life UV-protected polycarbonate. Includes 2 roof windows w/automatic openers, 1 large rear wall window, and 1 barn-style door w/ lock.

Compare Before You Decide

A greenhouse is an investment in years of growing. Explore how our polycarbonate greenhouses compare to others on the market, from structural integrity to material quality and long-term performance.

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Key Features

German Engineering

Designed and manufactured in Germany

Aluminum Frame

Powder-coated in black for a modern style

Curved Sidewalls

Rounded design helps shed snow and deflect high winds

Automatic Roof Vent Opener

Opens and closes based on temperature

Rear Window

Provides important additional ventilation

Dutch-Style Door

Split door for access and airflow

Secure Door Lock

Keeps the greenhouse closed when not in use

Victorian Cresting

Decorative cast metal finials

Clear Plexiglass Front

Clear front panels for maximum light and visibility
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Specifications

Glazing: 8mm twin-wall polycarbonate (side walls)
10mm twin wall polycarbonate (gable ends)
Frame: 13 gauge powder-coated aluminum extrusions
Color: Black

Riga 4 Black

  • Suggested Retail: $10,999
  • Length: 14'
  • Width: 9'8"
  • Peak Height: 7'7"
  • Area: 135 sq. ft.
  • Doors: 1 Barn Style Hinged Door w/Lock
  • Door Size: 2'6" W x 6'7" H
  • Windows: 2 Roof Vents, 1 Rear Window
  • Window Openers: 2 Automatic (Roof)
  • Roof Vent Opening: 22"x 40"
  • Window Size: 3'5" x 2'1"

Riga 5 Black

  • Suggested Retail: $12,999
  • Length: 17'6"
  • Width: 9'8"
  • Peak Height: 7'7"
  • Area: 165 sq. ft.
  • Doors: 1 Barn Style Hinged Door w/Lock
  • Door Size: 2'6" W x 6'7" H
  • Windows: 2 Roof Vents, 1 Rear Window
  • Window Openers: 2 Automatic (Roof)
  • Roof Vent Opening: 22"x 40"
  • Window Size: 3'5" x 2'1"

Accessories

Comes Standard With

N/A

Can Also Add

Frequently Asked Questions

Where is the Riga greenhouse made?

The Riga series of greenhouses is made by Hoklartherm in Apen, Germany. Hoklartherm has been manufacturing high quality greenhouses in Germany for over 40 years!

Do I need a permit?

You might need a permit. Not everyone does and even sometimes those who do need a permit do not apply for one. Each municipality sets their guidelines for what types/size of buildings need a permit in their area – sometimes this is based on square footage or whether they consider it a “permanant structure” – but this is all decided by your local permit office. If you are applying for a permit, you should always go through this process BEFORE you order your greenhouse – depending on local wind/snow load requirements you may need additional reinforcements or supports to reach your local requirements. You may also find other restrictions for placement that may mean you have to limit the size or location. If you are going to get a permit, it is always best to know the restrictions ahead of time.

Do you provide structural certifications for the Riga/Riga XL greenhouses?

We have general structural certifications to give you a realistic idea of the loads of each greenhouse. However, if you are applying for a permit you may need a letter stamped by an engineer certified by your state, or you may need a site specific certification. We do not provide these state or site specific documents, but they are available for a fee. Conversely, we may be able to point you toward an engineer who can assist you with the documentation you need. Keep in mind, each location/state has different load requirements. If you are in a location that has higher load regulations, you may need to purchase additional reinforcements.

What is required to prepare the site for my polycarbonate greenhouse? Do I need concrete to anchor it?

The greenhouse site must be level, this will help ensure an easy and straightforward assembly. Your greenhouse must be anchored securely to the ground. This is best done in one of two ways. You may pour a concrete strip foundation (to the frostline is recommended by the manufacturer) or you may purchase a foudation/base frame kit for the greenhouse. The unique foundation frame eliminates the need for concrete. It hooks to the bottom of the greenhouse and is buried in a trench that is about 5″ deep all the way around the greenhouse. This will securely anchor the Riga greenhouse. Occassionally, we have also had people pour full concrete slabs and use anchor screws with the supplied L brackets – if you do this, please account for drainage. You can also find a wealth of information to prepare for your greenhouse in the first section of our assembly manual, which can be downloaded on the product page.

Resources & Documentation

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