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Mud Hub Greenhouse Kit Assembly Guide

Welcome!

 

If you are about to assemble a Mud Hub Greenhouse, we thank you for your support & trust. We know you will not be disappointed with the result of having the freshest food you can hope for, along with the pleasure of growing it yourself.

If you are considering purchasing a kit, we hope this guide will inspire you to move forward. You can do this!

This greenhouse was designed with you in mind: no more needless bending, poor soil, and critters to spoil your gardening experience.

Once assembled. Have fun. See what crops work well in certain areas. You will find multiple microclimates even in this greenhouse. Plant crops you never dreamed of growing, experiment. 

To fully enjoy your Mud Hub Greenhouse experience, please follow instructions in the latter part of this guide for windy conditions, especially in New Mexico. It can play havoc with all kinds of structures, permanent and non-permanent. While we have limited control over hurricane forces, prescribed measures can be taken to protect poly film covers and doors.

A  new  adventure  awaits  you !

Suggested Tool List (Not Provided)

  • 2 pair of sawhorses (to cut & sand lumber)
  • 18” concrete or wood stakes, if needed for leveling 
  • (2) 50’ extension cords w/ 3-way outlet connectors 
  • Compressor /compressor hose/air staple gun (optional, if no power outlet nearby)
  • Circular saw, chop or miter saw
  • 1 drill & 1 driver with appropriate driver bits for various screws
  • Phillips head bits
  • Star bits
  • 3/8” wood drill bit
  • 7/32” or 3/16” metal drill bit
  • (1) 6’ level, (1) 4’ level
  • Hammer tacker/stapler & 5/16” staples
  • Framing square/speed square
  • Hammer
  • Pencils
  • 25’ measuring tape
  • Chalk line & chalk
  • 100’ string line
  • Sander & 80 grit sandpaper
  • Shovels/tamper/pick axe (for fine tuning site)
  • 48” bar clamp/24” bar clamp/large scissor clamps
  • Tin snips
  • Hack saw or saws all
  • Paint brushes, rollers and pans
  • 5/16” deep socket w/extension to fit drill
  • 3/8” deep socket w/extension to fit drill
  • ¼” spade bit (wood)
  • Carpet knife or blade
  • 4’ & 6’ step ladder
  • Red or yellow crayon

Required Tool Attachments & Fasteners (Provided)

  • 1 1/4” cabinet screws
  • 3 1/8” ext. cabinet screws w/bit
  • #10 x 3” star drive bugle head screws w/bit
  • 5/16” carriage bolts, washers, nuts
  • Self-tapping screws

Components/ Materials/ Hardware

Below are selected components, materials and hardware needed to assemble complete greenhouse kits, including winter polyethylene covers. Not shown or provided are lumber, tubing, swaged end tubing, galvanized trim, door, door hardware and door panel.

Recommended Site Preparations

  1. Level site to 3’ beyond door facing sides and 2’ all other sides.
  2. If unit is 12’ x 20’ with one door, leveled area should be 16’ x 25’.
  3. Optional leveling material: 3” of crusher fines spread and tamped.
  4. Locate footprint in mostly sunny area; do not locate under or over utility lines.
  5. Orient unit in the direction where gardening will be less severe.
  6. Best assembly weather conditions are 45f degrees and higher, low to no winds and dry.
 
 

Raised Bed Assembly, Top & Bottom Courses

1.  Below are the layouts and cut lists for two of our more common greenhouse size requests. See complete cut lists for all other size offerings toward the back of this Assembly Guide

10 x 12 Unit Raised Bed

  • (2) 2 x 12 x 12’s cut to 11’-9”, (2) 2 x 12 x 12’s cut to 12’ lengths 
  • (1) 2 x 12 x  10’ cut to 9’-9”, (1) 2 x 12 x  10’ cut to 10’
  • (2) 2 x 12 x 8’s cut to 7’-9”, (2) 2 x 12 x 8’s cut to 8’ lengths
  • (1) 2 x 12 x 10 cut to 3 lengths of 3’-4”, (1) 2 x 12 x 10 cut to 2 lengths of 3’-1” & 1 length of 3’-7” (It is important to follow sequence to not mis-cut 10 footers.

(all cuts are made out of 2  x  12’s)

12 x 20 Unit Raised Beds

  • (2) 2 x 12 x 20’s cut to 19’-9”, (2) 2 x 12 x 20’s cut to 20’ lengths
  • (1) 2 x 12 x 12 cut to 11’-9”, (1) 2 x 12 x 12 cut to 12’
  • (2) 2 x 12 x 16’s cut to 15’-9”, (2) 2 x 12 x 16’s cut to 16’
  • (1) 2 x 12 x 12 cut to 3 lengths of 4’, (1) 2 x 12 x 12 cut to 2 lengths of 3’-9” & 1 length cut to 4’-3”

Material Order List for Cut Size

Note: Kits that are purchased do not include lumber for raised beds, benchtops and supports and door framing. Check material lists for specific size units for purchase at a local lumber outlet.

Separate lumber cut lists will be issued by Mud Hub Greenhouses to owners requiring 2 doors for their units.

 

Numbers in boxes represent the number of units needed to satisfy an order of particular materials.

Lumber and metal/steel should be cut and/or assembled according to cut sheets supplied in this guide or in separate materials, as provided by Mud Hub Greenhouses.

Materials to be ordered are for units with one doorway. Materials needed for two doorways will be provided on a separate sheet by Mud Hub Greenhouses.

Top & Bottom Layer Lumber Layouts for Mud Hub Greenhouse Widths

Note: Not all greenhouse kit sizes are shown. Lumber cuts for the widths shown will be accurate for the 10’, 12’, and 24’ wide units. Refer to lumber cut lists and use diagrams below as a guide for unit sizes not shown below. Note that lumber length dimensions that are 9” are always on the bottom layer.

12 x 20 Units

Layout & Cut Pattern

10 x 12 Units

Layout & Cut Pattern

24 x 24 Units

2 x 12 Lumber & Hoop Leg Placement Plans

2.  Assemble first course of 2 x 12’s following diagram above

3.  Use (4) 3” cabinet screws at corners.

Figure 1.
Figure 2.

4.Be sure to align tops of 2 x 12’s to each other before screwing. Put in top screw first, then, bottom screw. Set corners flush with each other as corners are fastened with screws.

6. Square up unit: Note: This is important to ensure that the prefabricated steel hoop profiles fit properly. Measure to outside corner of both diagonals to square unit by moving box so diagonal measurements are equal. Then, unit is “square” (figure 8).
Figure 4.
5. Attach temporary 2 x 4 to front short sections on each side of door opening so unit is a solid rectangle. For 10 x 12 units, the front pieces and aisle width are 40”. For 12 x 20 units, that measurement is 48”. Screw 2 x 4 flush with tops of 2 x 12’s so desired aisle width is established.
Figure 3.

7.  Once 1st course is assembled and squared, use levels to level 2 x 12’s to each other. Concrete or wood stakes may be needed to lift and secure 2 x 12’s into position. Use 1 5/8” cabinet screws for this purpose.

Typical 4 x 4 Bench Support Layout for 24’ Wide Unit

  • Quantity of 22 ¼” cuts according to length of unit.
  • For front and back door access, replicate front plan profile.
  • Refer to page 12 of Assembly Guide for other notes.
Figure 9.
Figure 10.

Raised Bed Protection

  1. Staple 6-mil polyethylene to inside of 2×12’s. Cut 24” width out of roll and lap corners 6” – 12”.  Do not cover top of 2 x 12’s with plastic.
  2. Insert hardware cloth, which comes 48” wide. Use 2×4 with mallet or hammer to pre-bend edges and lap sides 2” up for a 12 x 20 unit. 
    Note:  (3) pieces of hardware cloth need to be cut, (2) long runs and (1) shorter back run. Figure the actual measurements from inside of board to inside of board for the 3 pieces and add a length of each piece for easy attachment to the sides. For a 12’ x 20’ unit, those measurements are 21’ end to end for the long sides and 13’ for the short side. Lap up 6” all the way around for a 10’ x 12’.
  3. Prior to lifting ‘basket’ into raised bed sections, use snips to cut diagonals into hardware cloth and remove squares from corners for easy fold down into raised beds. (See figure 10).
  4. Lower ‘basket’ into raised bed section, one section at a time, with folds snug against bottom of bed corners and sides (figure 11).
Figure 11.

5. On end basket pieces, use snips to cut hardware cloth at inside corners of raised beds, so as to lay flat before securing over polyethylene lined beds (See figure 12.)

6. Drive 1 1/4” cabinet screws through hardware cloth into 1st course 2×12 bases every 6”.   

Note:  24’ wide units are to have the same hoop spacing as above.

Figure 12.

7. Use hammer tacker to fasten cloth to 2 x 12’s. Be sure hardware cloth is as taught as possible.

8. Lay weed barrier over hardware cloth and secure with landscape stables, as needed (See figure 13). (As an option, wait until greenhouse is completed to do this step to avoid tearing the material.)

Measure Layout of Hoop Legs

1.  Place tape measure at long side of raised bed inside corner. Mark tops of raised beds as shown below and carry through line to insides of raised beds with the use of a framing square & red or yellow crayon. Align hoop legs to these lines prior to installation of hoop legs to raised beds.  

Figure 14.

3.  Align mark with top of 2×12’s. Push hoop leg into corner and situate so that the bend is perpendicular to the long side of the bed and facing the inside. Plumb the leg bend as in figures 15. Use 2 x 4 and 4’ level so that the leg bend is flush with face of 2 x 4. Eventually, the hoop rafter will fit into the opposing  corner legs to complete the full hoop. Drill thru pre-punctured holes in corner hoop legs with 5/16” wood drill bit into 2×12’s while holding hoop legs plumb.

24’ wide units are to have the same hoop spacing as above

2.  Mark all hoop legs 22” up from bottom on the outside of hoop legs with felt tip pen (see red line, figure 15). This mark aligns all legs with the top of the raised bed and ensures consistent height of legs.  

Figure 15.

Note:  (3) pieces of hardware cloth need to be cut, (2) long runs and (1) shorter back run. Figure the actual measurements from inside of board to inside of board for the 3 pieces and add a length of each piece for easy attachment to the sides. For a 12’ x 20’ unit, those measurements are 21’ end to end for the long sides and 13’ for the short side. Lap up 6” all the way around for a 10’ x 12’.

Figure 16.

4. Fasten with 5/16” x 3.5” carriage bolts, with heads facing out and washers and nuts on the inside of beds. Notice in figure 20 the offset of carriage bolts in corner hoop legs, typical of all four corners. Install interior hoop legs in similar fashion. Be sure the bend in the upper leg is visibly square with the opposite side. 

Figure 17.

Sequence of Installing Connectors for 10’ and 12’ Wide Units

  1. The two end hoops, one at the front and one at the back, need to have purlin clamps slid onto hoop rafter or hoop legs before that rafter is attached to its’ legs. Start by sliding end purlin clamps  ‘A’ & ‘G’ (figure 19) over each of 4 corner hoop legs with bottom part of clamp biased to the inside (figure 20).  Let connector rest on top of 2x 12’s until ready to be permanently tightened.

2. Next, insert set screw couplings ‘H’ & ‘I’ (figure 19) onto each corner hoop leg, place at end of hoop leg bend and overlap by half the length of coupling; Make sure screws are pointed down and tighten screws  (figure 18). 

Figure 18.

The lettering of Figure 19, below, is as follows:

A, B, D, F and G are clamps that attach the purlin to the hoop rafter and legs.
The purlins run the length of the greenhouse.

H and I are the set-screw couplings that join the hoop legs to the hoop rafter.

C and E are the strut connectors that show the vertical struts installed. The front struts to the side of the future door can be seen, already installed, in the photo.

3. Next, starting at one end of the hoop rafter, slide purlin end clamp ‘F’, then strut connector ‘E’, then ridge purlin clamp ‘D’, then strut connector ‘C’ and lastly purlin end clamp ‘B’. Remember to bias the bottom part of purlin clamps to the inside (Figure 19). With clamps and connectors in place, attach hoop rafter to legs. Do this to both front and back end hoops. Note: the end rafter purlin clamps are the ones with one bolt and nut/washer set instead of two bolts. The two bolt clamps are for the interior hoop rafters. 

Figure 19.

Sequence of Installing Connectors for 24’ Wide Units

The connections and sequence of installing connectors are slightly different for 24’ wide units. There are several reasons for this. First, the hoop profiles come in 5 sections instead of 3. Secondly, tubular sleeves that are provided are used to connect hoop legs to arcs, instead of set screw couplings. See page 25 for 24’ Wide Unit connection diagram.

Figure 20.
Figure 21.

4. After setting end rafter hoops into set screw couplings ‘H’ & ‘I’, on both sides, tighten screws. Both end rafters are now installed. The two end hoops are now completed. Next are the interior hoops. The purlin clamps that fit the interior hoops can be installed after the rafters are attached to the legs. 

Interior Hoop Rafter Installation

Place set screw couplings at hoop leg ends, with screws facing down, and tighten.  Place hoop rafters into couplings and tighten screws.

  1. To begin forming each hoop profile, it is recommended to lay pieces down on a flat surface so the parts will be in line with each other, for before connecting the two arcs with a short ridge length provided.  
  2. The ends of each arc have swaged ends that fit into each end of the ridge tubing. Secure each end of the ridge piece to the arcs with self-tapping screws. See figure below for connection.
  3. At this point, it will be easiest to connect hoop legs with the slight bends at the ends to the raised beds, as shown earlier. 
  4. A very important item to remember is that interior rafter connection sequences will be different than those of the first and last rafters or hoop profiles. For interior rafters, complete the arc profile by connecting the legs to arcs. This is done by first marking the midpoint of  a 1 5/8” x 8” inside sleeve connector with a felt tip pen. Place inside either hoop leg or arc length to the mark just made. Secure inside sleeve with a self-tapping screw or two into all hoop legs first. When sleeve is secure, slide the arcs as described in step 2 over the sleeve to meet the hoop legs and repeat securing with one of two self-tapping screws. Repeat for each side. Be sure that all pieces are aligned, using either a framing square or level before securing screws. Since only the “hanging” 2-piece cross connectors for connecting purlins to arcs are used, there should be no fear of having to undo any of the hoop parts because of a forgotten connector.  
  5. As with the 10’ and 12’ wide units, the situation is a little different for the end rafters because connectors are threaded thru the hoops instead of hanging off of them. Therefore, thread the cross-connectors for lowest purlins thru hoop legs first and let them hang there until installing the purlins. 
  6. Next, continue with the proper sequence for end rafters. Remember, the arc profile is still on the ground at this point! Connectors a,b,c,d,e, & g are the end-rafter cross-connectors to the purlins that will be installed a little later. Connectors h,I,j, & k are the adjustable angle connectors used for attaching the vertical struts to the arcs. See figure below. You are now ready to connect the arcs to the hoop legs.

End Strut Placement and Installation

  1. Place front struts 1” from inside front corners of raised beds on each side of the aisle. See figure 23.
  2. While holding in place, insert into strut connectors on end hoop rafter.
  3. Plumb the strut and then tighten all set screws of connector; then, drill thru pre-punctured holes in struts through 2 x 12’s. Insert carriage bolts and tighten with nuts and washers. Be sure strut is plumb throughout this process.
Figure 22.
Figure 23.

4. Place rear struts along and inside of rear raised bed, 40” in from outside corners for 10 x 12 units and 48” in for 12 x 20 units. See figures 29 & 30. Secure, insert in strut connector and plumb before tightening screws.

5. Drill through 2 x 12 at puncture points and install carriage bolts.

Figure 24.
Figure 25.
Figure 26.

Purlin Assembly and Attachment

  1. There are two choices in purlin lengths: 21’ or 10.5’, 1 3/8” fence railing. If only 10.5’ lengths are available, insert swaged end into regular end of next piece and fasten with self-tapping screw. 
  2. Measure 19’-9 ½” for 12 x 20 or 11’-9 ½” for a 10 x 12 unit and cut with hacksaw or sawzall & file burrs. Purlin location is marked with felt tipped pen on end hoops.
  3. Repeat until all 5 purlins are cut and ready to install.
  4. Save scrap remainders of tubing and use as 4”-5” long connectors for 1” emt polyethylene cover roll up assemblies, as needed later on.
  5. Next, lay one purlin on top of second course of 2×12 on one of the long sides. Purlin should be placed from outside of end hoop leg to the outside of the other end hoop leg. Push purlin against all hoop legs and mark with felt pen every purlin at its’ center where it contacts a leg. This is an easy way to mark for the purlin/hoop locations that will be used when installing the ridge purlin (D in figure 19).
  6. The two lower purlins (A & G in figure 19) attach at bend in hoop legs. To locate the three other purlins, measure from one leg bend over the top of the hoop rafter to the opposite leg bend. Divide this measurement in half to find ridge purlin location (D in figure 19). Mark purlin locations at end hoops with felt tipped pen. See figure 24.
  7. Having marked with felt tipped pen on both end hoops at all 5 purlin locations, stretch a chalk line from end to end, snap lines on undersides of interior hoops to mark locations of purlins.  Use a felt tipped pen to highlight chalk marks.

 

 

Figure 27.
Figure 28.

Note: for 24’ wide units refer to figure above” (refer to figure number). Also add, “a & g locations for purlins will be the underside of tangent points where bends are beginning

Figure 29: Purlin locations for 10’ & 12’ wide units

Figure 29.

8. Attach interior purlin clamps on centerline of chalk lines.

9. Starting at ridge, install purlin through clamps and tighten. Each purlin should line up to the outside of the respective end hoops. End hoops may have to be moved slightly to “fit” the length of the purlin. Temporarily secure mid-span sag of purlin to interior hoop with rope or strap – this will snug the purlin to the hoops and make clamps easier to install.

10. Now install the interior ridge clamps remembering to line up sharpie marks on purlins to those on rafters. To use interior purlin clamps remove bolts and fit both pieces over hoop rafters so the legs point down and are bent towards each other. Reinsert bolts and lightly tighten with washers/nut. 

11. Attach remaining purlins to rafters at marked locations.  

12. Once gently tightened at all rafter-purlin locations, be sure square base of carriage bolts are in square holes of clamps while tightening nuts. Use 5/16” deep socket with a ratchet or a drill. Legs of clamps should draw close together as fasteners are being tightened.

 

Figure 30.
Figure 31.

Note: On 10 x12 units there are 20 total clamps; on 12 x 20 units there are 30. (See Figures 31, 32).

Door Framing (read instructions for appropriate size unit)

For a 10 x 12 unit the space of the aisle is 40”. The vertical 22” 4x4s that were screwed into the 2x12s in the aisle in front are set back from the aisle corner edge by 3.5”. This allows screwing in two vertical 2x4s (actual width is 3.5”) on either side of aisle to frame in the door at the front corners (see figure 40). The length of these boards (the “legs) is 1” longer than the height of the door. For example, if door is 80” high, the legs are 81”

  1. Screw (4) 3” bugle head screws per leg into the 2x12s, so bottom of 2 x 4 is aligned with bottom of 4 x 4. Adjust 2nd leg by moving up or down to make sure the tops of the 2×4’s are level to each other and plumb.  
  2. Next cut a 2×4 header that will span between the strut connectors. Make the length tight against connectors as this will stabilize the door. This header will rest atop the legs and will rest against strut connectors (figure 41). Plumb the verticals to the header and use two screws to secure header to legs. The aisle width between the 2×4 legs is now 37”. The door should be 36”wide. 
  3. Install hinges on face of door to manufacturer’s instructions. Center the door in opening (figure 38) and raise it so there is 3/8” gap at the header. The gap between the door and legs should be equal on both sides. Attach other half of hinges to edge of door leg. If after doing this, the header is not square to the door, mark how much needs to be cut from the tall leg, unscrew it from the header and 2x12s, cut and reassemble. If the framing and leveling of the raised beds was done correctly then the door opening should be square. 
  4. For a 12 x 20 unit the space of the aisle is 48”. The door opening needs to be narrowed to about 37”. The vertical 22” high 4×4’s are screwed into the 2x12s in the aisle in front at the inside corner edge (see figure 35). The width of the (2) 4x4s is 7”. Subtract that from 48” = 41. (2) 2×4 door frame legs will narrow that gap by 3” to 38”. To shrink this measurement to around 37”, cut two pieces of 1 x 2 @ 22” lengths, drill pilot holes into 1 x 2’s before attaching to the door latch side, opposite hinge side, so that 1 x 2’s are flush with edge of 4 x 4.  Next screw one 2×4 leg to the short 1 x 2’s on one side and the other leg to the 4×4 on the other side. From here follow instructions for the 10 x 12 unit (the paragraph above) to complete this step.
  5. The 24’ wide units have a total height of 10’-2”. It is therefore necessary to stabilize the door framing the tops of the metal struts to either side of the doorway. The strut to strut horizontal dimension in that area is 7’-9”. A 2 x 4 x 8’ long length of lumber will be cut down to fit in between the struts, as shown in the figure below. Attach 2- 2 x 4 jambs to 4 x 4 bench supports as with other width units, with a 2- 2 x 4 header above the doorway. This will add more stability when attaching the mesh with screws are staples, in the next step.
Figure 32.
Figure 33.
Figure 34.
Figure 35.

12 x 20 door framing

10 x 12 door framing

Panels Over Entry Door

  1. Panels are not supplied as part of the Do-It-Yourself or “You Build It” kit. Owners typically have their own preferences for doors, which are also not supplied, but included in kits Mud Hub assembles. For 4-season units, it is recommended that Plexiglas or polycarbonate panels be purchased that will cover any screen openings. Stock sizes should frame openings by ¾” – 1”. If available, cut panel(s) to those measurements. 
  2. Attachment to the door can be as simple as predrilling oversized holes every 6” all around about ½” from the edges or using wood trim to frame in the opening (See figure 35A). Choose whether to leave on all year or remove per seasonal conditions.

Vinyl Coated Steel Mesh Cover Installation for 10’, 12’ & 24’ Wide Units

  1. Cut about 100 Velcro lengths of 6 ½” for attaching hex mesh to hoop arcs. Cut 4” strips of Velcro to attach shade cloth through the grommets at edges to hex mesh covers.
  2. Starting with the back end of the unit and using the 6’ wide panel provided, the length of material for a 12’ wide unit should be 12’-6”, and for a 10’ wide unit 10’-6”.
  3. Staple or nail long side edge of mesh to upper 2×12 of raised bed (figure 36), the edge of the mesh aligned with the outside edge of board.  The mesh lays flat on the 2×12 then rises up toward the hoop rafter. 
  4. Staple every 3 “. Make sure staple captures a segment of the mesh. The mesh should extend past the outside of the end hoop legs by 3” or so. 
  5. When bottom of mesh is fastened, stretch slightly upward and wrap around lower hoop legs and keep that tension as the Velcro is attached to hoops and struts about every 16”.
  6. For all 10’ & 12’ wide units, cut side panels adjacent to doorways to 4’-8” x 6’, if not already provided. 
  7. Align the 6’ dimension of 4’-8” x 6’ mesh panels with the top edge of the 2 x 12 raised bed, after bending mesh at a 90-degree angle. When placing, be sure the side toward the hoop arc completely wraps around before stapling to the 2 x 12. Consider using a Velcro tie or two to hold the mesh in place towards the top. It makes the attachment a lot easier when continuing with stapling, especially on windy days. Continue with the rest of the stapling and tying.
  8. Bend the other side of the same mesh panel to 90-degrees and place flush against the face of the door jamb opposite the door opening side. Trim excess material after stapling.
  9. For a 12×20 unit, roll the 4’ width of mesh up and over top at rear of greenhouse. Make sure both ends are equal length compared to the raised bed and even out the long edges over tops of the two rear-most hoops. 
  10. Choose one end and staple it to the top of 2×12 after having slightly stretched the edges towards the two hoops. Staple every 3” atop the 2×12.  
  11. With one worker stretching mesh outward and upward of one hoop to get the sags out and the second worker doing the same at other hoop, attach Velcro every 14”-16” or so as one works their way from one side to the other, continuously stretching and fastening. 
  12. Mesh material is supplied to accommodate long sides of 10’ & 12’ wide units. Use 4’ and/or 8’ wide rolls of mesh to cover the different size units. For example, a 12 x 28 greenhouse will require 7 lengths of 18’-4”, to roll out side to side, out of a complete 4’ wide roll of mesh, shipped directly to the site location from the vending source. If there is any confusion surrounding the number of lengths that are cut out of which size width, we will happily advise.

1.Install flashing over 2 x 12’s all around, overlapping @ corners. The flashing fits over the top of the 2x12s with the drip edge facing down. 

Figure 36.

24’ wide units will require mesh cut for the lengths listed below, as follows:

24’: 3- 32’-4” lengths for side-to-side panels

28’: 3- 32’-4” lengths, 1- 4’ x 32’-4” length

32’: 4- 32’-4” lengths

36’: 4- 32’-4” lengths, 1- 4’ x 32’-4”

40’: 5- 32’-4” lengths

2. Fasten with 1” cabinet screws. No pre-drilling necessary. Screw every 24”.

Figure 37.

Note:  We find it easier to install door and door framing before securing mesh to front panels and last 4’ section to the front of the greenhouse. In this way nobody gets in each other’s way and work continues on the phase after door is installed.

13. Cuts for front and back end panels will be the same for all 24’ wide units, except those requiring two doors. See figures below. Cuts for side to side panels will depend on the length of the units, as follows:

14. 24’ wide units will require mesh cut for the lengths listed below, as follows:

Shade Cloth Installation

Figure 38.
Figure 39.
  1. Maneuver shade cloth over hoops from front to rear. At front find midpoint of cloth and secure it to the midpoint of the door header, aligning the cloth hem with the lower edge of the header.  See figure 40.
  2. Stretch hem along the header and use (2) 1” cabinet screws at every grommet (figure 44). Don’t let fabric hang below header and interfere with door swing. 
  3. Go back and divide area between the grommets into thirds and screw in 2 additional screws through the hem. The corners of the shade cloth past the header will stay loose for now. 
  4. Go to the rear of the unit and stretch the cloth towards the back. Center the cloth on ridge purlin. Cloth will be short of end hoop rafter by inches. Custom cut Velcro strips to fit through shade cloth grommets and around end hoop.
  5. Stretch and Velcro the midpoint of the rear cloth to the ridge purlin then stretch the rear hem in a straight line down towards the sides and fasten with Velcro every 12”.  

6. Work your way back towards the front, stretching slightly downward on both sides, one worker each side. Place Velcro at every grommet; wrap 4” Velcro strips to the mesh, keeping long side of cloth parallel to purlins. The straighter the edges, the better it looks. 

7. After making your way from back to front on both long sides, pull front end corners down and out and attach with Velcro.

8. For 24’ wide units, pull shade cloth over front hoop to top wood cross member, as before, and fasten with cabinet screws thru the grommets and attach to mesh with Velcro ties thru grommets. Be aware that shade cloth will not pull all the way to the back of the unit. Fasten with Velcro ties as far back as possible while stretching shade cloth material.

Figure 40.
Figure 41.
Figure 42.

Bench / Counter Top Installation

  1. Cut 2×6 boards to required lengths to fit on top of interior u-shaped raised beds over top of 2×12 and 4x4s. 
  2. Line edge of 2×6 with inside edge of 2×12. The other 2×6 edge covers 4x4s and overhangs by ½” towards aisle. See figure 45.
  3. Miter ends at 45 degrees. 
  4. Use 3’ bugle head screws every 12” into 2×12 and into all 4x4s. Drive screws just below surface since surface will be sanded later.
Figure 43.
Figure 44.
Figure 45.

5.Notch bench top ends opposite mitered corners to butt into / fit around the door framing.

Figure 46.

Weatherproofing Exterior Wood

(This step can also be completed at the very end of the project. It maybe easier to seal all lumber at the start before assembling the unit. After cutting boards to proper lengths and sanding, place on a separate set of sawhorses and seal the better sides.)

  1. Remove any concrete stakes outside of raised beds.
  2. Sand raised bed interiors, exteriors, 4 x 4 supports, bench tops & door framing with 80 grit sandpaper and smooth edges and corners, if step was not completed after cutting board lengths at the start. 
  3. Brush and roll on exterior waterproof sealer of choice.

Poly Cover Installation: Front and Back Ends

  1. Place u-channel wiggle wire base at rear and front ends on top of raised bed 2×12 flashing with 1 ¼” cabinet screws or flat top self-tapping screws. Go from outside of hoop leg to outside of hoop leg in the rear along 2×12. Go from 2×4 door leg to outside of hoop leg at front end (see figure 47).  
  2.  Install channel to outside face of 2×4 door legs towards front edge; butt to top of 2×12 and then bottom of 2×4 door header. This piece should be in line with piece screwed into 2×12 top. (See figure 47).
  3. For all 10’ & 12’ wide units, poly film is precut into 4’-8” x 6’ for front panels adjacent to the doorways. If a front and back door is required for a particular unit, there will be 4 panels of 4’-8” x 6’. A 12’ wide unit with one door will have a back panel measuring 6’ x 12’-6” and for a 10’ wide, 6’ x 10’-6”. After affixing panels, trim off the tops to 2” to follow the arcs of the units. Long pieces of poly film that go over the tops will have factory edges that are meant to go from side to side. Of course, cut edges will vary depending on the length of the unit.
  4. At the rear end, stretch poly taut across bottom channel on 2×12. Let it overhang an inch proud of channel. Fasten to u-channel base with wiggle wire. The bottom is now secured (See figure 48).
  5. Snap clamps are precut into 2 ½” lengths. Hold plastic taught while carefully inserting snap clamps over plastic, placing corner of snap clamp first and then easing the rest so that plastic is secure.  Use a minimum of six clamps per corner over first and last hoops.  Clamps should be pushed and turned until fully around the tubing and mesh (See figure 49). Trim off excess poly, leaving several inches beyond snap clamps after secured.
  6. At the front end, install evenly across bottom channel on 2x12s on either side of the door with the 6’ dimension as the height. Secure at bottom with wiggle wire. Stretch poly up as before and place over the end hoop, starting at the ridge then working downwards on both sides. Fasten with snap clamps on top of the hoop and at channel with wiggle wire on 2×4 door leg as you go.  Make poly as tight and wrinkle free as possible. Poly is not needed above the door since shade cloth is there. 
  7. Trim excess poly film an inch beyond the channel at all sides. The cleaner this trim job is the nicer the greenhouse will “dress out.

  8. For 24’ wide units, follow the diagrams for front and back panel attachments.

Figure 47.
Figure 48.
Figure 49.
Figure 50.

Poly Film Roll-up on Long Sides and Attachment

  1. Single flange hooks are provided for both sides of the unit. They meant to hold the roll-up assembly and poly film in place when entire unit is covered for cold weather. Beginning 12” in from each end, attach hooks with a cabinet screw to top of upper raised bed 2 x 12’s. (See figure 52). Space the other hooks equally between the end hooks.
  2. Use appropriate piece of poly film provided for long sides, so that clamps go completely around the poly film when fastening to the end hoops. This, along with the placement and quantity of clamps will help to resist wind forces once poly film is rolled and secured to desired level.  
  3. The 1” EMT (electrical metal tubing) will attach to the poly cover at the top of the 2×12 raised bed on both long sides of the greenhouse. The EMT protrudes 6” from the front corner and extends 12” beyond rear corner of greenhouse. Use the small segments of fence railing provided to act as couplings, with two self-tapping screws per EMT to EMT connection.
  4. The 1” electrical metal tubing (EMT) typically comes in 10’ lengths. For a 12 x 20 unit that means piecing together two lengths of EMT plus an 18” section per side, cut from a 3rd piece, totaling 21’-6” for each side of the unit. For a 10 x 12 unit, cut 3’-6” off a second length of EMT, for each side, totaling 13’-6” of EMT for each side. 
  5. Connect a coupling provided to each end. Mark half the length of the coupling on the end of the EMT with a felt tipped pen, insert coupling to that mark and secure with self-tapping screws provided. 
  6. Insert double swivel into other half of coupling and secure with another self-tapping screw. This will be installed on the part of the assembly toward the back end of the unit. Just prior to rolling and securing poly film to both lengths of EMT, go to the opposite end or the front ends of these assemblies and mark 6” from the end with a felt tipped pen. This will help you align the assemblies and poly film evenly as you roll it up. At this point, you are ready to roll poly film onto this assembly on both sides (See figure 51).
  7. After placing EMT lengths on both sides of the unit, maneuver poly cover over hoops and make it even so that it hangs below tops of 2×12 walls on both sides 
Figure 51.

about 12”. On one long side rest full length EMT on top of 2x12s with the 6” mark aligning with the outer edge of the 2 x 12’s in front. Have 5 segments of ¾” diameter snap clamps provided at roughly equal increments on the ground from front to back so they are within reach before securing poly film to EMT. 

8. Next, at least two people and preferably 3 or 4, (invite your neighbors to help) need to pick up EMT and line it up with bottom of the cover. Tightly roll poly cover around EMT one revolution, evenly, and secure this wrap with the five plastic snap clamps provided. 

9. Continue to roll up slowly, carefully and straight so that the film does not wander off to the sides and is even on both edges. 

10. Repeat last procedure for the other side.

Figure 52.

11. The swivel and crank assembly are provided already connected to bar in the middle. The round appendage to the double swivel end easily fits into the poly film rolling bar and will need to be secured with a self-tapping screw. No coupling is needed besides the ones to connect sections of emt tubing to each other.

12. When cover is fully down the swivels will be positioned as in figures 59 & 60. When cover is fully up the swivels look like figure 61.

Figure 53.

Note:  The snap clamps will help hold the corners in place during strong winds and keep unit interior temperatures warmer during cold weather periods. Use enough of the snap clamps to ensure there is no opening for wind to get underneath the poly at the corners, possibly rip and effectively remove the cover by making it a sail.  As you roll the cover up to the desired height, depending on weather conditions, remove the snap clamps not needed and store where they can be found. 

Installing Wind Tie Down Ratchet Straps

For each strap length there will be two d-rings needed, one for each side of the greenhouse. You may notice that lengths of the ratchet strap is more than needed to tighten of loosen. Do not cut! You will need to connect the d-rings provided about 12” from the ends of each side with the 1 1/2” cabinet screws. 

Hook each strap end onto the d-ring on one side. You will notice a separate shorter length that has a hook, as well. First, you will thread the short pieces of strap through the slots of the long pieces by going up under and through the slot and down, over the metal end of the slot. Hook onto the d-ring. Then push in the lever of the ratchet assembly, which will allow you to flatten out the ratchet. Pull the tail of the strap towards you 18-24” or as needed so that the strap roll will not get too big as you tighten. 

Figure 54.

To tighten, push in the lever. It will allow the mechanism to fold up and enable tightening. The motion is up and down on the handle as you keep pressing the lever. When the strap is sufficiently tight over the poly film, you are done.

Figure 55.

When raising and lowering in the future, there is no need to remove the strap. Just press the lever, fatten out the ratchet and release as much of the strap from the roll as needed. Remember to take off or put on the snap clamps to the desired level of poly film before rolling up or down.  The snap clamps should be just above the desired level you want covered, at all 4 corners. Remember to always re-tighten the straps. You never know when a gust of wind will come along.

Figure 56.

Roll Up / Roll Down Instructions / Caveats

Now that you’re ready to finally fill those raised beds with good soil and start growing, you want to be sure the poly film cover lasts at least 5 -6 years. To ensure that will happen, good practices need to be followed so that you can enjoy fresh vegetables all year for years to come.

Wind forces are unpredictable. That is why it is critically important to keep clamps in place when not rolling up or down, as in Figures 59 and 60 . Before raising or lowering to a desired level, be sure clamps securing the poly film to hoops are not impeding the process, on all sides. Once satisfied with the position of poly film, be sure to secure once again with s-hooks and ties, as well as the snap clamps. Be sure to secure rolled up poly film cover with snap clamps provided.

 If weather is warm, an alternative solution might be to raise the poly film to the top on both sides and secure with the ratchet  straps. The wind will then blow through the unit and not drive the plastic cover up like a sail. 

As mentioned before, store the snap clamps not needed in a safe place where they can be found when needed again. If the choice is to roll down the poly cover in the event of weather coming, use all clamps provided at all four corners to ensure that the cover will be stable. 

Remember also to keep your door latched during windy conditions, as it is possible for damage to occur to the door and panel if left open.

Figure 57.
Figure 58.

LUMBER CUT LIST FOR UNIT SIZES

10 x 16 Unit Raised Beds

2-2 x 12 x 12 cut to 11’-9”

2-2 x 12 x 12 cut to 12’-0”

1-2 x 12 x 12 cut to 10’-0”

1-2 x 12 x 12 cut to 9’-9”

1-2 x 12 x 12 cut to 2 lengths of 3’-1”
& 1 length of 3’-7”

1-2 x 12 x 12 cut to 3 lengths of 3’-4”

2-2 x 12 x 16 cut to 16’-0”

2-2 x 12 x 16 cut to 15’-9”

10 x 20 Unit Raised Beds

1-2 x 12 x 12 cut to 10’-0”

1-2 x 12 x 12 cut to 9’-9”

1-2 x 12 x 12 cut to 2 lengths of 3’-1”
& 1 length of 3’-7”

1-2 x 12 x 12 cut to 3 lengths of 3’-4”

2-2 x 12 x 16 cut to 16’-0”

2-2 x 12 x 16 cut to 15’-9”

2-2 x 12 x 20 cut to 19’-9”

2-2 x 12 x 20 cut to 20’-0”

10 x 24 Unit Raised Beds

2-2 x 12 x 8 cut to 7’-9”

2-2 x 12 x 8 cut to 8’-0” 

1-2 x 12 x 12 cut to 10’-0”

1-2 x 12 x 12 cut to 9’-9”

1-2 x 12 x 12 cut to 2 lengths of 3’-1”
& 1 length of 3’-7”

1-2 x 12 x 12 cut to 3 lengths of 3’-4”

4-2 x 12 x 16 cut to 16’-0”

2-2 x 12 x 20 cut to 19’-9”

2-2 x 12 x 20 cut to 20’-0”

12 x 12 Unit Raised Beds

2-2 x 12 x 8 cut to 7’-9”

2-2 x 12 x 8 cut to 8’-0” 

3-2 x 12 x 12 cut to 11’-9”

3-2 x 12 x 12 cut to 12’-0”

1-2 x 12 x 12 cut to 2 lengths of 3’-9”
& 1 length of 4’-3”

1-2 x 12 x 12 cut to 3 lengths of 4’-0”

12 x 16 Unit Raised Beds

3-2 x 12 x 12 cut to 11’-9”

3-2 x 12 x 12 cut to 12’-0”

1-2 x 12 x 12 cut to 2 lengths of 3’-9”
& 1 length of 4’-3”

1-2 x 12 x 12 cut to 3 lengths of 4’-0”

2-2 x 12 x 16 cut to 15’-9”

2-2 x 12 x 16 cut to 16’-0”

2-2 x 12 x 20 cut to 20’-0

12 x 24 Unit Raised Beds

2-2 x 12 x 8 cut to 7’-9”

2-2 x 12 x 8 cut to 8’-0”

1-2 x 12 x 12 cut to 11’-9”

1-2 x 12 x 12 cut to 12’-0”

1-2 x 12 x 12 cut to 2 lengths of 3’-9”
& 1 length of 4’-3”

1-2 x 12 x 12 cut to 3 lengths of 4’-0”

4-2 x 12 x 16 cut to 16’-0”

2-2 x 12 x 20 cut to 19’-9”

2-2 x 12 x 20 cut to 20’-0”

12 x 28 Unit Raised Beds

2-2 x 12 x 8 cut to 7’-9”

2-2 x 12 x 8 cut to 8’-0”

3-2 x 12 x 12 cut to 11’-9”

3-2 x 12 x 12 cut to 12’-0”

1-2 x 12 x 12 cut to 2 lengths of 3’-9”
& 1 length of 4’-3”

1-2 x 12 x 12 cut to 3 lengths of 4’-0”

8-2 x 12 x 16 cut to 16’-0”

12 x 40 Unit Raised Beds

1-2 x 12 x 12 cut to 11’-9”

1-2 x 12 x 12 cut to 12’-0”

1-2 x 12 x 12 cut to 2 lengths of 3’-9”
& 1 length of 4’-3”

1-2 x 12 x 12 cut to 3 lengths of 4’-0”

2-2 x 12 x 16 cut to 15’-9”

2-2 x 12 x 16 cut to 16’-0”

10-2 x 12 x 20 cut to 20’-0”

2-2 x 12 x 20 cut to 19’-9”

12 x 36 Unit Raised Beds

3-2 x 12 x 12 cut to 11’-9”

3-2 x 12 x 12 cut to 12’-0”

1-2 x 12 x 12 cut to 2 lengths of 3’-9”
& 1 length of 4’-3”

1-2 x 12 x 12 cut to 3 lengths of 4’-0”

2-2 x 12 x 16 cut to 15’-9”

2-2 x 12 x 16 cut to 16’-0”

8-2 x 12 x 20 cut to 20’-0”

24 x 24 Unit Raised Beds

1-2 x 12 x 8 cut to 2-3’-9” lengths

1-2 x 12 x 8 cut to 2-4’-0” lengths

3-2 x 12 x 8 cut to 8’-0” lengths

3-2 x 12 x 8 cut to 7’-9” lengths

2-2 x 12 x 12 cut to 9’-10 1/2”

2-2 x 12 x 12 cut to 10’-0”

1-2 x 12 x 12 cut to 2 lengths of 5’-10 1/2”

1-2 x 12 x 12 cut to 2 lengths of 6’-0”

3-2 x 12 x 16 cut to 15’-9”

9-2 x 12 x 16 cut to 16’-0”

24 x 28 Unit Raised Beds

1-2 x 12 x 8 cut to 2-3’-9” lengths

1-2 x 12 x 8 cut to 2-4’-0” lengths

1-2 x 12 x 8 cut to 8’-0” lengths

1-2 x 12 x 8 cut to 7’-9” lengths

2-2 x 12 x 12 cut to 9’-10 1/2”

2-2 x 12 x 12 cut to 10’-0”

1-2 x 12 x 12 cut to 2 lengths of 5’-10 1/2”

1-2 x 12 x 12 cut to 2 lengths of 6’-0”

2-2 x 12 x 12 cut to 11’-9”

2-2 x 12 x 12 cut to 12’-0”

1-2 x 12 x 16 cut to 15’-9”

7-2 x 12 x 16 cut to 16’-0”

2-2 x 12 x 20 cut to 20’-0”

2-2 x 12 x 20 cut to 19’-9”

24 x 32 Unit Raised Beds

1-2 x 12 x 8 cut to 2-3’-9” lengths

1-2 x 12 x 8 cut to 2-4’-0” lengths

3-2 x 12 x 8 cut to 8’-0” lengths

3-2 x 12 x 8 cut to 7’-9” lengths

2-2 x 12 x 12 cut to 9’-10 1/2”

2-2 x 12 x 12 cut to 10’-0”

1-2 x 12 x 12 cut to 2 lengths of 5’-10 1/2”

1-2 x 12 x 12 cut to 2 lengths of 6’-0”

2-2 x 12 x 12 cut to 11’-9”

2-2 x 12 x 12 cut to 12’-0”

1-2 x 12 x 16 cut to 15’-9”

7-2 x 12 x 16 cut to 16’-0”

4-2 x 12 x 20 cut to 20’-0”

24 x 36 Unit Raised Beds

1-2 x 12 x 8 cut to 2-3’-9” lengths

1-2 x 12 x 8 cut to 2-4’-0” lengths

1-2 x 12 x 8 cut to 8’-0” lengths

1-2 x 12 x 8 cut to 7’-9” lengths

2-2 x 12 x 12 cut to 9’-10 1/2”

2-2 x 12 x 12 cut to 10’-0”

1-2 x 12 x 12 cut to 2 lengths of 5’-10 1/2”

1-2 x 12 x 12 cut to 2 lengths of 6’-0”

4-2 x 12 x 12 cut to 11’-9”

4-2 x 12 x 12 cut to 12’-0”

3-2 x 12 x 16 cut to 15’-9”

9-2 x 12 x 16 cut to 16’-0”

4-2 x 12 x 20 cut to 20’-0”

24 x 40 Unit Raised Beds

1-2 x 12 x 8 cut to 2-3’-9” lengths

1-2 x 12 x 8 cut to 2-4’-0” lengths

1-2 x 12 x 8 cut to 8’-0” lengths

1-2 x 12 x 8 cut to 7’-9” lengths

2-2 x 12 x 12 cut to 9’-10 1/2”

2-2 x 12 x 12 cut to 10’-0”

1-2 x 12 x 12 cut to 2 lengths of 5’-10 1/2”

1-2 x 12 x 12 cut to 2 lengths of 6’-0”

2-2 x 12 x 12 cut to 11’-9”

2-2 x 12 x 12 cut to 12’-0”

3-2 x 12 x 16 cut to 16’-0” 

1-2 x 12 x 16 cut to 15’-9”

2-2 x 12 x 20 cut to 19’-9”

10-2 x 12 x 20 cut to 20’-0”

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