Introduction: Greenhouse

hi all, I am new to your site, but I thought I would share with you all my greenhouse projects, I am a reasonably competent diyer ( well I think so , others may disagree) with the basic tools, nothing more fancy than a sliding mitre saw and an electric drill, I am by no means a pro, I just enjoy tinkering about and making / bodging stuff.

My wife wanted a greenhouse and had priced some people to come i and make one for us, prices started at £18k, there was no way I was paying that for something I thought I could do myself, so I was straight down the Wood yard to buy lots and lots of 40x90 treated timber which made the majority of the frame. The green house sits on a 2ft high single block wall, we didn't worry about a cavity wall as damp wasn't really an issue in a greenhouse. The frame is made of 12 individual frames. Each frame consists of a simple box frame with either 1or 2 uprights, joined at 90degrees to The box frame to give either 2 or 3 windows. The middle window of each section was then fitted with a temporary piece of 6 mm ply to prevent the frame warping when it is bolted together. The frames are then secured to each other and 80mm x 80mm corner posts with coach bolts, Silicone sealant was applied to all the joints between the frames prior to them being screwed together. The frame can then be secured on to the wall with 6 inch concrete bolts. The frame is 130 cm tall. The frame is topped off by a piece of 90mm x 35mm on which the eaves for the roof would resist. Once bolted and secure the temporary ply in the window frames can be removed. The green house is 3m x 5m with a ridge height of 4.2 m.

The next phase was the roof, this was a simple a frame structure. A 5 metre piece of 6" by 2" was used as the main beam Two roof eaves were added at each end and cross struts were temporarily added to help secre the eaves. The simple roof frame was then lifted in place by me and 3 friends using ladders. This is probably not safe and not the proper way to do it but it worked for me, But I have never been a great one for health and safety! ( hopefully that won't be on my headstone!!!)

The roof eaves were then added one at a time being bolted through the top joist and then down into the frame at the opposite end. all the joints in the frame were countersunk and then filled so no holes are visible. The down frames were also added at each end which starts to make the whole roof more stable. There are 10 windows on the back roof the front roof has the porch area so it is more complicated. The roof was made more secure with the two 45 degree corner braces which you can see in the picture, and a large support which run down from the apex to the wall at each gable end,

The roof on the front porch has to incorporate the gutters and the lower roof joist at the apex of the porch roof, This joist runs straight to the back of the greenhouse and helps tie the structure together. The gutters are complex and I wish I knew a simple way to do them, but unfortunately it took me lots of measuring re measuring, measuring again , cutting, swearing and re measuring before I got them right.

Once the final roof eaves were in place I began to fit the wood for the glass to rest onto into each of the frames, this is laborious and annoying as you see little progress for the hours of work you are doing. Once this job was done we painted the entire structure with a wood preservative that does exactly what it says on the tin.

Glazing was straight forward. The roof was done in polycarbonate, it's more expensive but much safer to fit when using such large sheets and up a ladder, it is also so much lighter and doesn't overload the roof. Once glazed , all the windows were finished with an edging strip to secure the glass. This is even more time consuming and equally as boring as fitting the interior glazing support peices. The gutter section on the roof was lined with lead and then teh polycarb laid over the top to make sure the water didn't leak in through the gutter.

Each roof eave was capped with shaped 10mm thick strip wood , which finished the roof nicely and help secure the room poly carbonate. The other advantage of poly carb on the roof is that it can be drilled and then screwed to the glazing supports to give it extra strength.

The apex was then finished with a run of flashing and then decking boards screwed to the main eave to finish the roof and make it water tight.

The green house was fitted with electric lights and a timed irrigation system which waters from the water butt ( made from a bushmills whiskey barrel, the smell drilling it out was fantastic).

There were interior raised beds made from single skin walls and then a concrete was laid. And the exterior rendered and dashed to match the house.

Hopefully this has given you some inspiration, it took most of the summer to make, but was enjoyable, and it has now survived two very wet and wild irish winters and hasnt blown down yet, so I must have done something right, it has also produced some lovely strawberries and more runner beans than a small country could consume in a year.

If you need any more info, photos or a bag of frozen runner beans then pleas give me a message.

Amazingly this whole project only earned me a week of brownie points from my wife, who soon started talking about her next project?





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    11 Discussions

    great looking greenhouse, I'm planning something similar myself for this summer! Can I ask you what thickness of polycarbonate did you use for the roof?

    thankyou, sunharmonics,

    oooooh, this is so amazing. congratulations (:

    hi love grove, thanks for your comments, I am afraid I can't give an exact price as materials tended to be bought in stages as I worked out what I would need next. The wood all came from a local builders merchants as did the blocks cement and hardware etc, my total bill with them was probably about £750. Roof was expensive , but that is because we went for polycarbonate not glass, so that was about £ 800, but in glass it would have been cheaper. Glass for the sides was £ total including paints render stones, founds for the wall cement floor and trimmings I would estimate it cost about £2000 to build, which is £13000 less than we got quoted to build it.!!!!!!! I have found some more photos and will put them on later.

    Nice greenhouse. How much did all of the materials cost overall if u don't mind me asking

    hi vyger, we tend not to have much in the greenhouse over winter, but my wife has an old paraffin heater that we use if there is going to be a late frost. Initially we had planned to have a small section of the roof done with a slate tile and then we could have had a wood burning stove with a chimney running up through the roof, but that idea never materialised. The glazing is really simple, I try to do things as simply as possible. Inside the whole of each frame I screwed in a thin peice of 8mm thick strip woodstrip wood , this was set back 20 mm from the front of the frame. Then silicone was applied to the front edge of the strip wood and the glazing pushed into the silicone. The glazing was supported at the bottom with a couple of pin nails to stop it slipping down before the glazing could be secured. It was then secured from the outside with a strips of quadrant pinned into place round the whole of the frame. Hopefully these photos will help explain.


    Is there a heater for cold days?

    I would appreciate some detailed pictures of the glass to wood method you used.

    thanks, I am sure you will, my wife has plenty more projects lined up for me.

    Wow! The greenhouse looks amazing. Thank you for sharing your build. I hope we see more from you in the future!