How to build a raised play fort
Step 5. Fixing the lower side rails
Bolt the middle and bottom side rails in place. See the picture on the right.
Do not fit the top side rails until such time as the floor has been installed.
Step 6. Fitting the floor
The floor will (or should) sit neatly on the rails and will not need further fixing.
It is simply a matter of picking up the floor and dropping it in.
Step 7. Fixing the upper side-rails and the beam
The two top side-rails (1 each side) can now be bolted in place.
Make sure all the horizontal frame members (rails) are level and all the vertical members (corner uprights) are plumb (upright) and that the structure is square, and then...... add (nail on) all the diagonal braces except for the one at the corner where the ladder goes (this brace is in the way of a bolt hole and can be added when the ladder is in place).
Each brace is fixed to the underside of a middle rail and a corner upright.
The beam. Fix the beam in place ensuring the font and rear walls are parallel. The beam can be fixed to the collar ties each end with nails, and then further secured with metal galvanized strap nailed to both the beam and the collar ties.
Step 8. Starting the roof, fitting the middle rafters
Fix the roof boards to ONE SIDE OF THE PLAY FORT ONLY, then make up the middle rafters which are two pieces of 70mm x 45mm x 1200mm (1 1/2" x 2 1/2" x 48") bolted together at right angles.
Next slide the middle rafters over the beam and under the roof boards. Clamp the middle rafter to the bottom roof board to hold it steady while nailing.
See roof board fixing detail in the next step (step 9.).