I built this tree house during the glorious summer heatwave of 2003.
I used 4″x3″ timber for the legs and base. Prior to construction, I had soaked the ends of the wood in preserver for several days. The post holes were dug just slightly bigger than the posts – probably about 6″ diameter. I poured pea shingle in each hole to rest the posts on. This ensures good drainage and prevents the bottom of the posts getting waterlogged. I used PostCrete to fill the remainder of the holes around each post.
I reinforced each corner with a 4×2″ brace fixed with 8″ coach screws, to stop the structure from racking
Then I installed 4×2 floor joists, leaving a larger gap on the first one to allow for the floor hatch
I laid the floor using 2 sheets of 8×4 of ¾” exterior grade plywood. Using CLS timber I created the studwork for the side walls. (I’ve only just learned that CLS = Canadian Lumber Standard – I always wondered!). I held it square with temporary battens
I made 6 identical roof trusses from cls, strengthened at the apex with a ¾” plywood plate.
Then I installed studwork at the gable end wall
Then I created a window frame
At the front of the tree house the floor extends out and overhangs the front by about 4 feet. This is made from the side rails which are 12ft long and run from back to front. I supported the overhang with longer 4×2 braces, bolted on as before. One of the 12ft lengths was twisted at the end so I had to shape all joining pieces to allow for this.
I fitted 4×2 joists for the balcony part.
On the front gable end wall I installed noggins to act as door frame and window frame. I added diagonal bracing to prevent racking.
Prior to cladding the walls I stapled-on building paper to act as a water barrier in case driving rain blew water up under the cladding.
Then it was time for the shiplap cladding. Each end of the cladding was soaked in wood preserver.
I used decking as a floor for the balcony
Then it was time for the roof, using Onduline corrugated sheets
Next I papered and cladded the gable end wall
And the same for the front gable end
Time for paint
Finishing the roof over the balcony was awkward because I had to overhang the edge. I laid a ladder flat on the balcony and got two family members to stand on it to weigh it down while I walked out on the ‘gang plank’ to work on the roof!
I fitted a door
Influenced by the houses I had seen in Bavaria on holiday that year, I designed the balcony balustrade in a similar style
Fifteen years later, 2018, it’s still standing
although threatened to be engulfed by nature!
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