Green Bug Ltd - Blog from a greenhouse builder

Alleyway greenhouse complete

24/10/2020

My customers asked me to build a greenhouse over this alleyway. It makes great use of this space and the greenhouse feels quite spacious inside and taller than I'd hoped it would be - the doors are almost 2m high and the roof rests comfortably above that.

I added a full length shelf as requested. The shelves, and even the brackets, are removable for ease of cleaning and for flexibility. The work station folds down out of the way when not needed.

The roof windows have boxed upstands and full drip edges to prevent any water ingree - the pitch of this roof is below 10deg. They are fitted with auto openers.

I cut a chase in the garage wall and installed a Code 4 lead flashing and then added guttering on the wall which flows to a downpipe which runs into the raised bed.

Back to Surrey for another "Steve"

16/10/2020

My customer had sent me some photos of where the greenhouse is going so I knew there would be some concreting to do to extend the concrete slab outwards. Of course I didn't know what the depth or width of the new base would be so I ordered up more than I thought I would need, then made some trips to local suppliers to get more material.

The first job was to remove the turf for the foundation. I laid plastic visqueen sheeting over the soil (to stop the concrete going hard too quickly) and poured a 6 inch deep slab in one pour.

Once I'd built the walls we could see the extent of the void to fill. I bought 50 solid concrete blocks and laid then in a bed of mortar before pouring a slurry of concrete mix over the top and between all the gaps.

I could then carry on building the walls as normal.

The blue / grey engineering bricks will sit mostly below ground eventually. The plan is for a raised path to connect the greenhouse doorway with the rest of the garden (which is also raised) and have large soil beds on either side.

Hi Robin,

I hope you got home safely and thank you again for coming down to build the base of the green house. It looks amazing and we can’t wait to see the completed greenhouse. Your work ethic and workmanship is truly wonderful.

Big one update

9/10/2020

I made another trip down to the Surrey massive this week carrying 97 sheets of glass many at 2.5m long (8ft in old money) to make a start on the structure of this greenhouse.

I glazed most of the roof and sides and all 3 gable ends. However, I wanted to mock up the valleys on site so I could work out the angles of the glass before ordering these up. This will be completed in the final visit where I'll complete the roof and sides, cold frames along the front, fit the ridge and install a set of work tables and shelving for what will become a gardening school.

Alleyway update

1/10/2020

I made a good start on the alleyway greenhouse. The gap is wedge shaped - getting wider at one end so I made sure all the timber was oversized so I could cut it down to fit on site. Finally I could measure up for all the different glass shapes for the roof. I was delighted at the eventual height - it feels much more spacious inside and the doors are almost 2m tall.

I'll return to the workshop to order the glass and build the doors now and return here in a couple of weeks to complete.

Preparing for another "Steve"

24/9/2020

I spent most of this week building and painting another "Steve" greenhouse in accoya. I won't install it for a few weeks yet as I need to build the walls, and order up the glass beforehand but most of the structure can be made from plan in readiness.

I'll be on the road, and sleeping in my van, for the next 3 weeks - first to a greenhouse over an alleyway in Gloucestershire, then back to that really large one to put the structure up before laying the base for this "Steve" greenhouse in Surrey.

Greenhouse over an alleyway

16/9/2020

This 4m long greenhouse will cover a narrow alley between a garage and garden wall with a doorway at both ends. The width is wider at one end than another and the garage roof slopes up higher at one end.

I have built most of this structure and will cut the rafters down to size on site. I cannot work out what the final glass sizes will be until the structure is up as each one will be different along the roof.

I toyed with the idea of increasing the greenhouse roof height as it follows the line of the garage but it worried me that the glass in the roof would be made to twist. I tested this by building a scale model to the site dimensions and, whilst the rafters would look good (top picture) when I substituted that for flat plywood it was clear I couldn't change the height of one part of the roof without some serious twisting. Good to know - so I can lay the roof level at it's lowest point but that should still be 10deg pitch.

The structure for this one is now painted and stacked in the workshop ready for my first visit in a couple of weeks.

A big one...

21/8/2020

This one's massive - 8m long by 4m with a porch and long cold frames along the front. I've spent some time producing and painting most of this greenhouse beforehand so I can deliver a lot of it when I go down to build the walls. The photo above shows the roof rafters laid out after painting in the sunshine.

For the first time in years, it tool me two separate visits to complete this base build. There were a few snags - the wrong engineering bricks were delivered (which they swapped over) and I found the soil here was very loose - not compacted enough to build walls on. I ended up digging out the whole area around 18 inches deep (barrowing out around 30 tonnes of soil) to reach compacted ground hard enough to start the foundations.

The inside floor will have an intricate tiled design undertake by local contractors at a later date. As preparation I laid and compacted quarry stone blinded with sharp sand so they have a solid base to work on.

I'll build this greenhouse in two further stages. As most of the structure is completed and on site already I will install the glass for the roof and sides and then return to complete the valleys, cold frames and shelving shortly after that.

A "Richard" in North Yorkshire

6/8/2020

There are planning restrictions which apply even for greenhouses - the main one being if you build within 2m of a shared boundary the roof height should not be greater than 2.5m. I have built a few designs where the roof height is under 2.5m and the Richard is one. You can find lots of useful guidance and rules which apply on the planning portal website - the link is given in the box below.

Planning Portal

Although small, it still feels roomy inside with plenty of space for shelving and height for growing up from the ground in pots or on the 2 tiers of shelving space. There is plenty of ventilation with 2 auto-opening roof windows and two manual windows in the sides which can be left open. This greenhouse has a lot of detail and bags of character.

"Mark" with mods complete

27/7/2020

"Robin,
Just incredible and way beyond our wildest dreams.
Thank you"
Anne and Chris

This one has 4 valleys which meet in the centre - like a "plus" sign shape if seen from above with a front doorway leading through to a set of double doors opening to the view of the lake and fields behind.

Having the two ridge boards interlock at the centre gave this greenhouse lots of rigid strength from the very beginning - before any rafters or support bars were added this greenhouse wasn't budging an inch. It also adds a nice detail in the centre.

I added a cold frame to each corner - some of which can be used for storage whilst others will toughen up the young plants before transplanting to the garden.

I was also asked to build 2 tall obelisks with lathed finials to sit either side of the greenhouse for climbing plants in the veg border.

I added 2-tier painted shelving either side of the main porch and over a "Monty Don" style potting bench. I was also asked to build a work table which can be moved outside or around as needed.

This was a large project for me. I really enjoyed it - it really feels like one of my best. Working for Anne and Chris was a real pleasure and great fun.

"It has been a pleasure from start to finish and we love it, thank you very much!"
Anne and Chris

"Tim" against an old barn wall

14/7/2020

This was a tricky build - not least because of the sloping ground requiring an extra 3 courses at one end and compacting of material to bring the floor up to the new levels. But also the old barn wall was very uneven and sloped away from the greenhouse by over 2ft from the base to the top of the ridge. I was also hampered by rain throughout and lost 3 days of inactivity due to constant heavy downpours. The bright side was this job was very near home so I could carry on back in the workshop after having to leave site again each day.

But I got there and I'm extremely pleased with the end result and I'm sure the owner will have many happy years enjoying this accoya greenhouse. I added a row of cold frames at one end and a brick sided raised bed inside - which will be perfect for growing tomatoes direct into the ground. Instead of the usual paved flooring I was also asked to lay the brick setts which worked out really well in a t-shaped pattern - leaving a gravel edge for standing pots on or as a water run off from watering plants.