Juicing the Greenhouse

NOTE: This customer is sharing their steps to wire their greenhouse. We advise all customers to hire an electrician unless you are 100% sure you are capable of the project.

Part 1: Adding Electrical to Greenhouse

Adding electrical to your greenhouse is an individual experience. It can be accomplished in several ways. Our project goal was to replace a figurative cold frame into a fully functional greenhouse complete with light, fans, heating mats, cooling and heating before summer.

Materials and Time Required
This project took more trips to our local hardware store than we expected. The final tally for materials was $100 and a weekend to run electrical wiring to the outside of the greenhouse.

Tools Used  Materials Used*
• Bosch® PMD4 stud finder
• Box knife
• Commercial grade heat gun
• Extension cord
• Flat head screwdriver – large and small
• Greenlee® 438-10 fish tape 8-10
(100’ x 1/8” x 0.60”)
• Kneeling pads
• Latex gloves
• Magnet pole
• Needle nose pliers
• Philips screwdriver – large and small
• Pipe cutter
• Pocket knife
• Power drill
• Various size paddle bits
• Screwdriver bit
• Rubber mallet
• Ruler
• Sharpie marker
• Shovel
• Small flashlight
• Wire stripper – large and small
• Wire cutter
• Voltmeter 
• 2 bags (5 pieces) Carlon® non-metallic PVC ½” conduit clips (E977DC-CTN)
• 1 bottle of Guerrilla Glue®
• 1 box of 50 GB 14-8 AWG copper crimp sleeve connectors (10-311C)
• 1 16 oz. can Carlon® solvent cement
• 4 Carlon® UA9ADB non-metallic PVC conduit elbows ½” (16) 90D Std Rad SCH 40 Belled
(3/4” outside diameter)
• 6 Carlon® non-metallic PVC conduit pipes
(1/2” inside diameter)
• 6 Carlon® non-metallic PVC ½” conduit pipe connectors
• 100’ Cerro® wire indoor 14-2 NM-BW ground
• Drywall screws
• 2 Leviton® Smartlock Pro GFCI
• 2 spools of electrical tape – 1 green and 1 orange
• Paint matching current house color
• 2 Taymac® Outlet box cover horizontal mount duplex (wet location) CH 1005
• 2 Taymac® SB350S 3 holes ½” outlet box (wet location)
• 1 tube wood putty

* I have listed the manufacturer of each part so you can easily locate them in your local hardware store.  This is not an endorsement of companies listed, but just a reference for what was used on DIY project.

Stepping it All Out
For our greenhouse, the electrical wiring was sourced from an electrical outlet located on the outside wall of the garage not being utilized. To give you a sense of what it took to install the electrical wiring, I broke the steps out.

Note: These steps are an overview only and should not be used specifically as step-by-step instructions. Each project will have its own unique site challenges.

Prep Work and Safety Measures
Step 1. When hiring an electrical contractor, be sure to secure any necessary permits required in your local area. Always make sure your contractor is licensed, bonded and call for references before starting any project.

Step 2. Contact your local Utility Notification Center before trenching PVC pipe. Calling before beginning any excavation prevents damage to underground facilities, service interruptions to the home, and bodily injury. 

Step 3. Pre-measure the length from the outlet to the greenhouse to make a count of piping, elbows and joints required. The PVC conduit is much cheaper than the joints.

Step 4. Clean area near water and electrical areas. Remove any obstructions for a clear view of your working area(s).

Step 5. Charge all cordless tools prior to beginning project. Remember that you may be turning off the outlet(s) nearest to your working area.
Select an electrical charging outlet away from the primary work area.

Step 6. Pick a clear and dry day to work.

Step 7. If you need to stop work midway, be sure to “cap off” any wires that will be live before restoring power via the breaker panel to the outlet.

Do not leave live, exposed electrical connections unattended.

Electrical Outlet Wiring





Step 1.
Turn off the power to the outlet being re-wired via the breaker panel inside the garage. Using a voltmeter, check to make sure the power is off. Double check with the power on and verify no power is flowing with the breaker off as well.
Note: If you have a security system, it is advisable to make sure this is turned off.







Step 2. Remove electrical outlet cover and face plate with screwdriver.







Step 3.
Locate jumper and wire knock-out stamping location. A “knock out” or “KO” is a partially stamped opening in electrical enclosures that allows quick entry of a wire, cable or pipe via connector or fitting to the interior. Since the outlet on the side of the house is a four way outlet, we were able to take power from the wires and feed it off the main electrical. Punch out the knockout square with the flat head screwdriver to run the new electrical wire.







Step 4. Unscrew the electrical outlet box housing. Tap on wall to see if it is hollow or filled with insulation. Use a stud finder to make sure you are not drilling into a main stud.

Outside garage walls in newer construction have the tendency to be hollow. Make sure to drill hole *above* the seal plate using a stud finder or you may end up with multiple holes that will need sealed with wood putty and repainted to match the siding. (see photos below). Tip: Hollow walls make it easier to fish the wiring through.







Step 5. Using a paddle bit attached to a power drill, drill a hole in the house siding where the electrical wire will be attached the outlet and run out to the greenhouse.







Step 6. Unroll the electrical wire. Run it out to the greenhouse leaving ample amount to run inside the greenhouse as well. Extra wire can be trimmed off later. To make the wire glide through the wall easier, wrap green electrical tape around the end of the grounded wire. With orange electrical tape, attach the metal fishing tape to the electrical wire before placing inside PVC elbow in wall. Test the wire into the wall to make sure it will fish out properly to the electrical outlet.







Step 7. Insert the PVC elbow into the wall. If needed, place green electrical tape around PVC pipe that is closest to the wall to create a tighter fit. Using Gorilla glue around pipe perimeter, seal out water and pests that may try to gain entry. Pound PVC elbow into wall with rubber mallet. 
Note: If you have to drill one or more holes to find a hollow area in the wall, fill any other holes not used with wood putty and repaint to match siding.






Step 8.
Fish the electrical wire through the elbow pipe and pull wire through the knockout on the side of the electrical housing. Secure electrical housing back into the garage wall. Screw metal spreader that holds the housing into the wall so it cannot be pulled out. This process is tedious and takes time. Adding the wiring through the knockout makes placing the housing a tighter fit.

Step 9. Check wiring with voltmeter. Using a wire stripper, remove insulation casing to expose copper wiring inside. Connect wires to electrical plug outlet. This procedure is akin to fine surgery and will take time to complete.







Step 10. Screw outlet face back into garage wall with drywall screws. Reattach outlet cover plate.

Piping Around the House





Step 1. Measure and mark conduit with a ruler and sharpie marker. Using a pipe cutter, cut the conduit needed to attach to main lengths of PVC piping. 









Step 2. Using a heating gun and screw driver, bend pipe slowly to the angle needed to attach the PVC pipe fastened in the garage wall to the first main length of the pipe.
Note: Bending and heating takes time and should be done carefully and slowly for best results.







Step 3. Fish the electrical wire still attached to the fishing tape through the straight pieces of PVC pipe. Liberally apply solvent cement at each PVC juncture point to seal out water and critters.
Tip: Wear latex gloves when applying PVC solvent. The glue is hard to get off hands and clothing. Be careful to keep the cap closed in closed areas as the glue has strong fumes.







Step 4. Run the wiring down through the wall and house it in PVC conduit piping. By hugging the underside of the siding, the wiring is protected from outdoor elements. Check your complete layout by laying out the pipe before gluing any elbows and connectors.  Corners that the pipe will need to bend around will require a 90 degree PVC pipe elbow. Repeat PVC conduit lengths, elbows, solvent application and wire fishing as required until you get to the back of the greenhouse.
Tip: Pulling wire through elbows can be troublesome and time consuming. Try to keep the total number of elbows needed to a minimum.








Step 1. Depending on where the greenhouse is located, you may need to measure and dig a trench to protect the PVC pipe and wiring. The conduit and wire is buried to prevent tripping hazards by leaving the conduit exposed on the ground. Digging the 18” deep x 3ft’ long trench from the house to the back of the greenhouse took about 30 minutes to complete.
Note: Be sure to check with your local wiring inspector in your area to determine the minimum depth required.







Step 2. Using another 90 degree PVC pipe angle, fish wire through pipe that is trenched before covering pipe with soil.

Run Wiring to Greenhouse
Step 1. Using a black sharpie marker, trace the GFCI plastic housing box outline onto the Solexx® greenhouse panel. Cut the Solexx panel with a standard box knife. Make sure the GFCI box fits snuggly into the greenhouse wall.







Step 2. Cut a length of main PVC piping and attach to the GFCI plastic housing box.








Step 3.
Run wire up outside wall and inside of greenhouse. Make sure to “cap” the electrical wires for safety with orange plastic caps if you stop project at this juncture.

Next Steps
Stay tuned details on how we finished the wiring project inside of the greenhouse.
Photos taken by Robert and Dawn Hummel.

NOTE: This customer is sharing their steps to wire their greenhouse. We advise all customers to hire an electrician unless you are 100% sure you are capable of the project.

This entry was posted in Greenhouses and tagged , , , . Bookmark the permalink.