Boardwalk between Decks

The next step was the pontoon connecting the two decks. Originally, my initial plans included a simple step running along the first deck... But ultimately, the idea of a pontoon was more original and integrated better into the overall design.

In the photo below, you can see the wood used to make the structure. Well, I must admit, I have a certain tendency to oversize my beams; the main ones being 11cm on each side (pressure-treated spruce), we should be able to fit 15 people on the pontoon without it budging; that was my goal, I definitely didn't want something wobbly.

The top of the pontoon is 79cm wide. This was dictated by the length of the almendrillo planks I'm using, to minimize waste: the planks are 240cm long, so I could cut three 79cm pieces from them, with a negligible final waste of about 2cm. Of course, you have to factor in the width of the saw kerf...
As a result, the dimensions of the structure were calculated based on the width of the top, taking into account an overhang of one centimeter for aesthetic purposes.
To make it look "clean," I used half-lap joints for the frame. The technique is simple, using a circular saw: you precisely set the cutting depth according to the section to be removed (see the marking in the first photo below). Then, you make a series of cuts a few millimeters apart (photo 2); the remaining pieces break easily, are then chiseled off, and finished with a rasp (photo 3). With practice, it's quick and easy, and it's much stronger than a flimsy joint made with screws and brackets... And it looks nicer, doesn't it? 😉

After an initial dry fit, the structure is assembled using PU (polyurethane) glue: this glue is moisture-resistant and expands as it dries, filling any gaps or play in the assembly. A few screws are added, but their main purpose is to ensure tightening while the glue dries.
The central beam is a leftover joist from the construction of the large deck; it actually supports almost no weight when walking on the deck, as the distance between the two main beams is small and the boards are quite thick... Its role is simply to allow the boards to be screwed in the center, to prevent them from "cupping" as they age!

A dry fit of the legs revealed that the entire structure was slightly too long, just by a few millimeters. It worked, but I wanted to leave a little play to allow for potential wood expansion; I didn't want it to put pressure on my deck. So, the legs were thinned by 6 or 7 millimeters, using the same technique: a series of cuts with a circular saw, chisel, and wood rasp...

The legs are doweled/glued in place. I use a Wolfcraft kit for the dowels: you drill one side, place the small copper nails (see photo) in the holes, adjust the piece opposite, a tap with a hammer and you have the precise marks to drill the second part...
Here, the dowels play only a limited role in the strength of the bond: with such a large contact surface, the PU adhesive is virtually indestructible. However, the dowels allow for perfect alignment of the foot and prevent any slippage during the clamping of the parts.

The entire structure has of course received its two coats of stain, just to be sure that it won't change over time.
All that's left is to cover it all with boards!

And here's the result, not quite final yet; two coats of oil/saturator still need to be applied to protect everything. The blades will take on their final color after being treated and spending a few weeks in the sun...

And there we go, I'm finally going to see the end of this Terrace Project ! 😉