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How to build a good base for your greenhouse
Text and photos: Louise, GreenhouseForum
The spring sun is finally here, and the evening hours are getting longer. Regarding the greenhouse, a little has happened as well. We have laid tiles and put up the greenhouse! But let me first take you back to the building process by starting with the excavation.
In this process, I teamed up with a colleague from Juliana Greenhouses, the greenhouse fitter Sanne and her husband Thomas, who has his own garden service company. We had them pass by to discuss what needed to be done to get ready to lay tiles. We agreed that my boyfriend and I should make sure to level the ground and excavate a pit of 8 inches so that 6 inches of gravel and 2 inches thick tiles could be laid.
Thomas Jensen owns his own garden service company called JT-Haveservice. Thomas has worked in the garden service business for more than 30 years. He has been a great help in our greenhouse project and has given us a couple of advice.
“I know that a stable and good foundation will form the basis of a perfect result for your greenhouse”
Thomas has 6 tips for you who want to place your greenhouse on tiles:
Tip 1: If you want tiles in your greenhouse, it is a good idea to lay the tiles before putting up the greenhouse.
Tip 2: Avoid dark tiles, as the greenhouse will get very hot.
Tip 3: The tiles should be level as your greenhouse should be level.
Tip 4: You should sweep the tiles with grit to fill all the joints, and then sweep the tiles clean before putting up the greenhouse base.
Tip 5: Take out the tiles where the base must be casted. When you have casted the base (remember to take diagonal measurements, to make sure the base is even), the let it dry for 48 hours.
Tip 6: To get a nice finish around the corner fittings screw off the base frame on the casted fittings and cut out the tile. After the tiles are put back, you can assemble the base frame again and then assemble the entire greenhouse.
As you can see on the below picture the height difference is larger on the right side, so the soil should be levelled from the tiles to the hedge.
This is what the result looked like after several days of digging by hand. Our neighbour was (thankfully) interested in the soil which he could use for his raised beds, so we gave him the soil and thus avoided a trip to the recycling centre.
The day before the day
I agreed with Sanne that like so many others, we could spend the Easter days laying gravel and tiles. However, we got disappointed as the tiles were not delivered by then. Of course, we were really annoyed about this, now that Easter is most often spent preparing for the garden season. Plan B was initiated, so we laid out gravel and got ready for the tiles that would come after Easter.
Wheelbarrow after wheelbarrow with clay gravel was laid, which Sanne had levelled and compacted a few times, so that it could be as flat as possible. Clay gravel is bottom protection gravel. It contains clay, so when you compact it, it becomes very hard. Subsequently, topsoil was laid on, which is not as heavy to move around on.
Poles were put into the ground I each corner with a string connecting them. The height of the string should be so that the planks are able to lie just below the string because the height of the planks are 2 inches just like the tile height. In this way, you make sure to get it all level.
It is a several days project
You would think that when the tiles are laid, all there would be left is to assemble the greenhouse, but no. I had to exercise patience, as the drying time of the concrete is essential. We had organized the steps carefully and the guide will show the different processes.
Utilize the waiting time to assemble the gables of the greenhouse, while the concrete dries. In that way, you can easily put up the profiles when the concrete has dried, and the tiles are put back.
The greenhouse is now up and we will see if I can get to buy some tomato and cucumber plants and start the season this year.
If you are curious to see the entire process, you can read about it here: I have gotten a garden filled with flowers and can you sell your old greenhouse.
Best wishes
Louise, GreenhouseForum

Om Drivhusklubben/Greenhouse Forum/Gewächshausclub
The Greenhouse Forum is the writer behind the articles that are about everything from reportages about unique projects in the greenhouse to Juliana employees sharing their experiences and knowledge about the greenhouse life.
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