My first hexagonal garden shed was constructed in 1998. the main timber construction was still fairly sound and I set off to move it to a new site further down the garden. Upon dismantling it I realised the error of building it on a wooden base. The base was made from toughened waterproof plywood, used in concrete casting but over ten years in contact with the earth it had completely rotted down. As the first shed was slightly too small I decided to build a new one. All was not lost with the original shed. A friend of mine was glad to take it away and rebuild it as a small garden room.
Step 1: Hexagonal Shed Site Clearance and Base
I decided that the new shed would be built to last and as my new hobby is stained glass, I would incorporate some nice windows The base was to be concrete so I needed to formulate the size and construction method. I was a bit low on carcassing timber for the main build so I used six of the pieces of 2x4 wrapped in clingfilm and reclaimed them like new once the base was cast and left to harden. I then laid down some heavy duty damp proof membrane, and build the floor frame. All the timber was painted with anti fungal/pest you name it preservative. Dropped in some 50mm insulation board between the timber then topped this off with 30mm waterproof plywood.
Step 2: Diagrams and Cutting Plans
I used some software to figure out the best way to cut the 8’ x 4’ sheets of ply with minimum wastage.
This was useful for all the ply cutting. I used Visio and Sketchup
Step 3: Modular Construction
I planned to build three sides of the shed in my workshop and then position them on the base and ‘fill-in’ the remaining three sides. This way I could build a jig to hold each side and they would end up being accurate, which is what I did. When I attached the three finished sides to the base I only had two blank sides and the doorway to build. I added a damp roof membrane to the side frames before nailing on the feather board cladding. I didn’t decide on the roof angle until the base was in place. This way I could mock up different angles with pieces of timber and some clamps to see what angle looked just right. I ended up with a 36 degree angle which seemed good as everything about the build was in sixes.
Step 4: Kingpin Made
The roof needed a large centre post so I made one from a recently felled tree. A few passes on the table saw and a bit of lathe work gave satisfying results:
Step 5: Roofing
it was difficult to hold all the roof beams in place until I had located them accurately. If I did this again I would build the roof frame on the ground and lift it into place once all secured together:
some galvanised floor joist hangers came in really handy for attaching the roof to the main body.
I positioned the cross members to coincide with the plywood roofing pieces. The rest of the roof was fairly standard, DPC, plywood, roofing felt then asphalt shingles. I used a plant pot to cover the finial and then felted it over. The finishing brass finial was cobbled together from a doorknob and the base of a discarded brass vase. Rather than trim the roofing felt I just lapped it over as I thought the extra layers wouldn’t hurt anything, although it did cause a bit of a problem selecting the correct length galvanised nails.
I used a string from the center of the top to line up the ridge tiles. I cut these tiles from the offcuts of the main shingles. I also narrowed them a bit at each cut so they tapered towards the top.
Step 6: Door and Frame
the front panel was fairly straightforward. I used a hardwood sill across the bottom and built on this.
The door was frame and skin construction and I used a few offcuts to reflect the window pattern. I added to this later as it was a bit too much like a star of David, although the windows ended up a bit Masonic.
I also added a plinth to the eaves. I eventually hope to add some art deco style corbles.
Step 7: Windows and Finish
the inside was insulated and then panelled with plywood,then finished with some hardwood trim. An internal light and some electical sockets plus many hooks, shelves and hangars. The final external finish was a blue green stone paint which still looks great nearly two years on
Step 8: A Few Years Later
Just repainted the shed with masonry paint as it is very durable. It's still looking ok with no major rot anywhere.