I give you this advise now bourn of experience and wish someone had given it to me before I built my Polycarbonate greenhouse. Trying to rescue a greenhouse at night when it’s raining and blowing a gale is no fun.
Ten things you must do if you’re getting a polycarbonate greenhouse.
1. Make the assumption that you’re going to lose some of it in the first strong wind if you don’t take this advise.
2. Choose a site that’s as site where your greenhouse is protected from the wind as best it can be.
3. Put a good heavy base down and fix your greenhouse too it but in any case you need your greenhouse fixed to the ground to stop it blowing away.
4. When you start the build if the instructions say it’s a two man build, it’s really four man build or better still get an octopus on the job.
5. The greenhouse is at its weakest when its half built so no stopping. This is a start to finish job that takes as long as it takes.
6. Building on a windy day is impossible, building in a light breeze possible but dead calm is best.
7. Aluminium nuts ‘pick up’ on Aluminium bolts if you over tighten them. To remove that nut will require you snap that bolt. This could lead to a shortage of nuts and bolts.
8. You are likely to be advised by the manufacturer to run a bead of mastic where the edge of the polycarbonate sheets meet the frame. Mastic not provided and only if you want too. My advice the more mastic the more likely your sheets will not blow out. Mastic the lot or use runs of sticky tape.
9. You may also want to add some strength across the walls and roof, I used domestic tile edging strips. They come in 8 foot lengths and have holes along their length that you can align with the slots in your frame.
Your remaining weaknesses are your door and your window. If either blown out, it could be
‘good night Vienna’ for your greenhouse so let’s deal with these last two weaknesses.
10. Fastening your door shut at night and do the same during the day if there is a strong wind, should take care of it. Fastening your window shut at night and doing the same during the day if there is a strong wind, should take care of it.