I have a three year old daughter and the closest playground is about a kilometer away (only roads without sidewalks), so I decided to make a playground in the garden, where she can play whenever she wants. As "luck" stroke, the roof of my house started leaking a lot and in one thunderstorm 2 square meters of the roof simply disapeared, so it was time for a new roof. The "luck" part is that a lot of wood from the old roof remained for me to reuse. This wood had been on the roof for about fifty years, but it was still pretty healthy (except the parts where the roof was leaking). The old roof didn't have any boarding, but a lot of short pieces remained from making the new roof, so I could also use those pieces for the playground. The only wood bought for this purpose are the four main vertical beams, because I simply didn't have old beams that were thick enough.

This instructable doesn't give a detailed description or plans of how to build the playground, but it will give some handy tips used in this project. I was planning to make the plans myself, but then I found a set containing hardware and plans for a commercial playground in the local D.I.Y. shop that had water damage and was 85% off. As for that price I wouldn't be able to buy the hardware (by far) I decided to go that way. I did do some modifications to the plans, because I found the original playground too small and didn't like the position of the stairs (on the opposite side of the slide).

Here's roughly what's needed:

4 wooden beams 10x10x250 cm
about 4.5 square meters of wooden planks (about 2.5cm thick)
20 wooden beams (8x5cm) with lengths varying somewere between 140 and 170 cm
6 bags of concrete (25kg)
2 liters of stain (don't try to save on this, use a good quality stain. This structure will be standing outside all year long, so a small saving on the stain won't pay off)
3 round bars (metal or wood) with a diameter of about 3cm and length 50cm (for the steps)
a lot of screws of various sizes
4 metal pins to fasten the playground to the ground (sorry, I don't know the English name for this)
1 slide
tablecloth (I'll explain later)
time and patience (especially when using recycled wood)

Step 1: Picking the Wood (when Reusing)

As the wood I was using had been on the roof for about fifty years, it wasn't easy to get usable pieces that were long enough. I started cutting out all the bad pieces that I gave to my neighbour who uses wood for heating. The good wood that was left I cut into the lengths that I needed.

When selecting the wood you should look for rotten pieces and cracks, they shouldn't be used.

After selecting the wood, every piece had to be inspected for nails and other objects that need to be taken out.

Step 2: Smoothing It Out

The wood I had was not processed (and old), so it was very rough with a lot of splinters. For the beams I used an electrical handheld plane. For the planks I used a belt sander, because they were a bit warped, what makes it hard to use a plane and a lot of material gets shaved off, what results in thin planks.

After the initial smoothing I rounded the edges with a router and used a vibrational sander to smooth it all out.

The holes that were present in the wood I filled with wood glue and sawdust (which I had more than enough after the sanding). Bigger holes need to be filled two or three times.

Step 3: Drilling

All the through holes in the wood should be drilled, so the wood won't split and the two pieces of wood will be pressed tightly together. The size of the holes should be one or two milimeters smaller than the thickness of the screw that should go through. Simply mark all the spots that should be drilled and start drilling.

For thinner screws it's not nescessary to drill holes in the piece of wood into which the screw fastens. For thicker screws (6mm and thicker) it's best to make a small hole (smaller than the inner size of the screw threads), so the wood won't split. For 6mm screws I drill a hole of 3mm.

Step 4: Painting

For the looks and endurance I used two colours of stain (yellow and green). I chose stain over laquer, because it's much easier to maintain. When laquer starts chipping, the whole thing needs to be stripped and painted again. With stain you can just periodically (about once in two years, depending on the climate) apply a new layer.

It's important to stain the playground before assembly, so that also the parts that are inaccessible after assembly get protection. I simply put all the wooden parts on top of some leftover beams and first stained one side and, after drying, the other side. Every piece received two coats.

Step 5: Ladder

As I was using a set for the playground, I had some nice galvanized metal steps. Instead of metal it's also ok to use wooden dowels, just watch out that they're strong enough.

The construction of the ladder is fairly simple. On each side of the ladder there's a wooden beam into which the steps are fastened. The holes that are drilled in the beams should be a little bit smaller (but not too much, because the wood will split) than the step that goes into it. The step gets hammered in place and secured with a screw in the backside of the wooden beam.

Step 6: Digging Holes

To provide stability and avoid rotting of the wood, the playground is standing on a concrete base. The base will exist of four seperate concrete filled holes, as the playground has four vertical beams on which it's standing.

First I measured and marked the spots were to dig. The digging was done with a small shovel, so the top of the hole could stay small. This is for safety reasons, so the top of the concrete has the same size as the beam that's standing on it. This way it's virtually impossible that the child will hit its head on the concrete when falling. The top of the holes is about 20x20 cm (I didn't manage to make it smaller, but in the step where the concrete is poured I will explain how to make the concrete the same size as the wooden beam). The depth of the hole is about 50cm. The hole is piramid shaped, meaning that the bottom is wider than the top of the hole (about 40x40 cm). Like this it's less likely the playground will sink into the ground, because of the large area carrying it. It also greatly reduces the chance of the playground tipping over, because of the additional weight of the concrete and the fact that a lot of ground should be moved to pull out the concrete.

Step 7: Building the Frame

The frame consists of a front and back side that are connected with beams. The easiest way of construction is to first construct the front and back side seperately on a flat underground (while laying down on the ground). When the two frames are constructed, they can be moved to the spot where the holes were dug and connected with the connecting beams.

It's advisable to do this final construction on the spot were the playground will be placed, as the finished frame is pretty heavy and difficult to move (especially for me as I built it all on my own).

When the construction of the frame is done, the whole frame should be leveled and straightened out. I used pieces of scrap wood that I put under the bottom connection boards to do the leveling. This is also the time to add the metal pins to the beams that will connect the playground to the concrete. For now they will be hanging in the empty holes, as the concrete pouring is done in the next step.

Step 8: Pouring Concrete

The concrete used is ready mixed dry concrete, that only needs to be mixed with water. The hole in the ground functions as the cast, so no wooden casting was used. After mixing the concrete, simply fill the holes with it. The top part is made tapered, so the top of the concrete has the same dimensions as the beam standing on it. Compress the concrete as much as possible. The gap between the edges of the hole and the concrete needs to be filled with ground and compressed, so the concrete has nowhere to go and it gets pushed against the beams, so they will actually be standing on it.

Step 9: Boarding

After the concrete has dried for a couple of days, the boarding can be put on the playground. You can now already climb on the structure, which makes putting the boarding easier.

This particular playground has a fixed sandbox under it in the original plans, but as I already have a sandbox I decided to do something else. I made flooring out of wooden boards that are connected with perpendicular boards on the down side. On the bottom I put a piece of foil against plant roots, which I fastened with nails. The bottom flooring is not connected to the playground structure, so it can be taken out in winter, which will prolong its lifetime.

Step 10: Adding Slide and Ladder

When the boarding is done, the slide and ladder can be added. The slide is fixed with four screws into the boarding on the deck. The ladder is attached using threaded rod that goes through the ladder beams and the beams of the playground. As the ladder is only connected on two points it could pivot, which is a hazard as fingers could get stuck in between. To eliminate this risk, a metal plate that runs between the ladder and the playground structure should be screwed in place on each side of the ladder. This way the ladder can no longer pivot. Another sollution would be to attach the bottom side of the ladder to the ground (preferably the same way the playground is connected to the ground).

Step 11: Adding the Roof

I can bet you were wondering what the purpose of the tablecloth is, I'll finally tell you. As I said I bought the set for the playground that had water damage (the box was completely torn). The original roof (made of fabric) was missing, so I used an old tablecloth (of woven polyester), that I was planning to throw away, for the roof. I was very lucky that the tablecloth was exactly the size I needed, so it could go on without any cutting and sewing. The tablecloth is fastened with screws into the beams of the playground (4 screws per beam). Be sure to use washers, or else the tablecloth wil tear. I used plastic washers to be sure they won't corrode. The playground has been standing for a year now and the roof is still intact. It survived the summer sun (in summer temperatures here are usually 30-35 degrees celcius), storms and winter cold and 30cm of snow.

Step 12: Finished, Future Steps

The playground is finished now. As I said it has been standing for a year now and the staining is still in a very good shape, so it's not yet nescessary to put a new layer, maybe next year or the year after.

I'm also planning to attach a swing set to the playground, I will update this instructable when it's done.