Constructing a Greenhouse
Kit Masters Greenhouse manufacturing Co. is dedicated to providing the back yard and commercial grower the opportunity to construct a durable and affordable greenhouse structure.
We offer complete kits or the key component parts for constructing greenhouses, such as arch corners, coupling sleeves, pipe clips, pylons, plastic film etc.
Using Kit Masters greenhouse component parts you can build any size greenhouse you want, or have room for, from 13' wide to 30' wide.
Copyright © 2001
This entire page may be printed or
copied in its
entirety, with no changes to any
portions thereof.
Greenhouse construction instruction featuring 28' wide or 18' wide.
For Greenhouse kits skip steps 3, 4.
Pylons
1. First purchase your 42"pylons from Kit Masters. Greenhouse arches should be spaced 5' apart. See: Order form for more info.
2. Lay out greenhouse foundation base and dig holes 9" in diameter and 18" deep. You can start by laying painted rocks on the four corners until all your measurements are the correct width and length, the diagonal measurements from corner to corner will both be the same when your lay out is square. When all your measurements are correct paint a 9" circle around your rocks and dig your holes. After your four corner holes have been dug you should stake and string line the perimeter of the greenhouse. Re-measure width, length, and diagonals to assure your accuracy.
Then concrete the four corner pylons in holes making sure lay out is precise
and pylons are plumb, (straight up) as even a small discrepancy will be obvious
when greenhouse is finished. Once the concrete in the four corners has set, you
can string-line them and use that string-line, a tape measure and a torpedo
level (small level) to concrete and plumb the rest of the pylons into the
ground.
Arches
For Greenhouse kits each part is numbered along with it's counter part just match the numbers and assemble with screws provided. Assemble each arch and stand it on pylons, make sure you put the trussed arches in their designated pylons. Assemble trusses to the arch while it's on the ground then stand the arch on pylons Do NOT assemble verticals at this point.
Rafters and legs for Arch corners
3. For a 28' wide arch use two 10' pieces of 1 1/4' EMT (electrical metalic tubing) pipe for your rafters.
Skip this if your structure is 20' or less wide. A 22' wide or wider structure will require 5 purlins (a purlin is a horizontal member on the structure connecting the arches together). Purchase two (two hole 1" Rigid pipe straps) for every arch you intend to put up. Drill a center hole in each of the 1" Rigid pipe straps use a 7/32" Cobalt drill bit. Make a center mark on the rafter pipe straddle your pipe strap across your mark and drill holes for mounting the pipe strap to rafter pipe. Mount pipe straps to your rafter pipe with 1/4" x 3/4" philips pan head sheet metal screws.
Legs
4.Cut one 10' piece of 1 1/4" EMT into two 5' pieces for each arches legs(side walls).
5. Now using Kit Masters arch corners, lay out corners on large flat surface
close to intended set up spot. Make sure arch is lying flat and level when doing
this to assure arch will be plumb when you stand it up. See: Order
Form for more info.
Insert rafter pipes into coupling sleeves provided on each arch corner (where applicable) make sure the pipe strap on the rafter faces the inside of the arch (that purlin goes on the inside of the arch). Then drill holes with a 7/32" Cobalt drill bit through the rafter pipe and screw together with screws provided with Kit Masters arch corners. Then slip the 5' legs into the coupling sleeves drill and screw together with screws provided.
6. With a person on each side of arch stand arch up and carry it to one end
of your greenhouses pylons, walk sides in and slip arch legs over the pylons.
Repeat steps 6 and 7 until all arches are standing.
7.
Now it is time to install your purlins Start with the lower outside purlins use
1" EMT pipe. Take your first 10' purlin and drill a hole using a 7/32
Cobalt drill bit, drill 3/4" in from one end of the pipe. Drill it on the
seam of the pipe as this will give you a straight line on the pipe to work from.
Then use a felt pen to mark the center of the pipe across the seam, drill it on
the seam and insert screws in the first two arches.
Then
using Kit Masters coupling sleeves insert sleeve into pipe strap on arch corner
and insert screw in the center hole on the sleeve. Then slip the ends of your
purlins into the coupling sleeves drill and insert screws until both side
purlins of the arch are done. See: Order Form for more
info.
8. Before you install any more purlins you must level your greenhouse, it's
easy by design. Start at the highest ground level arch as you can lift arches up
to level the greenhouse but you can't lower them without cutting a piece of the
arches leg off. Level greenhouse as you go by lifting arches up the pylons until
purlin is level, 
clamp a pair of vise grips on the pylon to hold the arch in
place. Then drill two holes through the arch leg and pylon for anchoring,
stagger the holes for added strength. Insert screws and move on to the next
arch until all the purlins on that side of the greenhouse are level. Then level
the other side using the same method.
When both
sides of your greenhouse are level install the top purlin then the rafter
purlins using the same method as the sides less the level as your structure is
already level. If you have any problem lining up the holes use a pipe wrench to
persuade it.
For greenhouse kits once all the purlins are on you can install your verticals to your trusses. measure the length between the ground and the bottom of the truss, and cut the vertical pipe less 1/4" of your measurement. Then slip the vertical over the pylon and truss plumb vertical with torpedo level. Insert screws on the verticals truss strap and drill and screw strap to truss. Drill two holes at the bottom of the verticals to anchor it to pylons. See: Truss & verticals for more info.
9. Now carefully roll out plastic down one side of the greenhouse. From the other side of the greenhouse throw a rope over the greenhouse, one rope every 20' to 30', then wrap a sock or rag in the edge of the plastic and tie the rope around the plastic and the sock or rag. Then carefully pull the plastic over the greenhouse.
Kit Masters pipe clips are easy to use simply pull plastic or screen tightly around the pipe and press on pipe clip with the palm of your hand. To remove clip place both your thumbs on one side of clip and press off.
10. Once the plastic has been pulled over the greenhouse start fastening plastic at one end of greenhouse, begin clipping plastic at the peak of one end and work your way down the arch. If you are constructing a greenhouse longer than 30' clip only enough to hold it on as you will have to come back to the first end and re-pull the plastic to get a tight fit. When you have clipped the first end go to the other end and pull plastic tight and clip it off. We recommend one clip per foot of pipe to be clipped. Then go back to the first end and re-pull it or ad clips as necessary. Space your clips far enough apart that you can put another clip between each clip your putting on this way you will have room to clip end wall plastic or shade cloth or screen to the pipe for enclosing your end walls or the sides of your structure.
After both ends have been clipped tight you may begin clipping the plastic to the sides, start in the center and put one clip in the center of the bay (between arches) then one clip next to the arch on each side of you then clip another centered between them and the center clip, totaling 5 clips per bay. This will help you keep the clips uniformly spaced.
See: Order form for more info.