Building a Greenhouse

Building a Greenhouse

My ideal glasshouse is a near-free upcycled style utilising old wooden windows and building walls to support it. My planning was a decision process, what do I want to build, what do I want to grow in it, and where’s the best place for this in our yard?

The outcome really needed to be an improvement on our makeshift shed. I knew I had the skills to build and make a suitable space for growing plants. The needs were simple:

  • Over 2 metres tall with a mono-pitch roof
  • water catchment
  • Reduce the wind, control the airflow
  • Hedgehog proof non-muddy work area floor
  • and able to catch the morning and all-day sun

Here’s the simple build list – building to my next-to-nothing budget, ideally under NZD 100. Although the actual build cost was $320, the most significant cost was the Clearlite and lumber to support the Clearlite.

  1. Design, plan, and measure
  2. Find and buy cheap old windows.
    • Collect the windows ready for installation.
  3. Find and buy old wood for foundation and framing (< $60 total)
    • Collect the wood and materials needed.
  4. Start planning the size and considering the windows
  5. Demolish the old shed & save the screws for reuse
  6. Create the foundation
  7. Create the first wall
  8. Finish all the walls and structure
  9. Put the roof on.

Tools required:

  1. Circular drop saw
  2. Screwdriver and plenty of various-sized screws (75mm to 100mm)


  • I had seen before starting this project that old wooden windows were freely and readily available on TradeMe. It was easy to source old windows, and after a few bids for $1 (one dollar), I was on my way with a small collection of various-sized wooden windows.
  • What I had not factored in was that the glass was weighty, and the wooden frames were solid wood, which meant that I needed help collecting the windows.
  • I left buying the Clearlite roofing to the last task, as several other factors needed resolving.


  • Collecting all the windows was quite an ordeal. Travelling to many locations to pick up large and heavy old windows, some in poor condition, others in near-new condition.


  • Already occupying the preferred location was a makeshift woodshed. The shed comprised pallets and other recycled building materials, some of which could be reused in the glasshouse build.


  • After the areas had been defined and cleared, the next task was to level and establish the foundation.
  • The design that I had made used piles to keep the main frame away from the soil. However, fitting my limited budget, the piles I had access to included bricks and treated posts. I used the posts to make four corner piles, and supporting these were stacks of bricks.


  • The walls are 90% windows, which are very heavy.


  • Quite possibly the easiest part of the build.
  • I purchased lumber and Clearlite (clear fibreglass corrugated sheets) and screwed these into place.


  1. In the first year, I recovered the total cost of the build from fresh produce.
  2. Fresh organic tomatoes, cucumbers, basil, and microgreens.
In the microgeens garden

In the microgeens garden

I started an indoor garden as a hobby during the New Zealand lockdown, and continued to develop into the winter months. We attended farmers markets and then went on to sell locally and to private buyers. The project continues to deliver microgeens to order. We have a dedicated growing space in a controlled environment suitable for 20 trays of greens. Our preferred microgeens are radishes and basil.

Jan 2021: Happening in the garden

Jan 2021: Happening in the garden

It’s 11th of January and I have a Product Manager interview at 10:30am, as a way to relax and prepare I decided I would get some gardening tasks completed and generally have a walk around in the cool of the day.

Kumera is growing well in the clotch.

Strawberries are continuing to produce. This year we forgot to cover the plants, but what we’ve discovered is a complete lack of blackbirds that would usually swoop in and gobble up bright red berries.

Cabbages are growing awesome, we’ll have to start harvesting these shortly.

Potato strip down the back path has worked well. Good crop and added diversity to the area beneath the fruit trees.

Apples are coming along nicely and are a bit unexpected considering the losses we’ve had after the late frosts, many of our fruit trees are bare this year.

The biggest delicious delight is found under a mass of peach leaves.

Water catchment

Water catchment

Having arranged the water storage for garden use, I noticed that there were other down pipes that could possibly reduce the amount of water caught. If I could reduce run off without increased chances of flooding, we should be able to collect more water per down pour.

The idea is that if water could be dammed at two points, we could increase the volume of water able to be drained into the barrels.

The catchment area is approximately 150 square meters.

The spouting is 5cm deep before it overflows into the house, and the dam wall is 2cm, which means that in a significant rain event the water can spill over.

Waiting for the next rain event to test system…

Water storage

Water storage

With our summer looming and the cost of domestic water increasing we have been increasing the amount of water collection and storage.

We have a water diverter on one primary down pipe that first fills a 1000 lt tank, this over flows then to 4 x 200 lt barrels. Additionally we have a 300 lt barrel that collects water from our shed.

The black barrels are gravity feed from the larger tank, via a 13mm plastic pipe that only starts filling the black barrel when the 1000 lt tank is 75% full.

The two black barrels are connected together and have plastic pipes that drip line to fruit trees at key points. Into these barrels a nutrient mix is added.

The two blue barrels have taps on them to manually decant water for buckets. The two blue barrels only fill when the primary tank is full.

Crop planting

Crop planting

It’s October and I have started planting out a row of various crops at the Springston patch. Thinking of the harvest and how different plants grow, I have planted:

  • Sunflowers to either cut and sell as flowers, or to cut and feed birds late into next winter when they are hunting for a feed. Sunflowers I noticed last year are quite frost hardy, and they protect other plants beneath.
  • Red, yellow and green runner beans that will climb the sunflowers.
  • Peas that also enjoy something to climb.
  • Zucchini of various styles, curly, zephyr, and more traditional ones.
  • Pumpkins if various types, orange, grey, big and small.
  • Luffas that will be cut up and used in washing.
  • Zinnias to add a burst of colour and possibly as a cut flower for sale or at least to freshen our house.
  • Broad beans as these fix nitrogen and also have great leaves for eating. Brilliant in a summer salad.
  • Crimson clover to help keep the nitrogen up and a crop that can be mowed between crops giving a valuable mulch.
  • Yarrow common white to increase pollination and to encourage bird life. Also for potential medicinal products.
  • Tomato’s in yellow, red and black.
  • Potatoes, ready for Xmas time
  • more to add.