How to make a frame for outdoor shower?

adapants

 Hi all, I'd love to get some advice on the construction of a frame for our outdoor shower which will be installed by a plumber in our garden. We are placing it in front of a paling fence, and were originally thinking of using a simple hardwood sleeper post, as one of the inspiration pictures above. But hardwood sleepers are hard to come by at the moment, and we have some salvaged hardwood fence posts in good condition I was thinking we could use instead. Each post is 120mm x 75mm and I could cut them into a total of 18 lengths of 500mm. I was thinking something like this would work below. 

Materials and plan : 

But I need advice on the best way to a) attach them all together, and b) have them structurally supported so they are free standing in an upright position. About 2m off ground is a good height I think. 

Should I screw them all together with a couple of vertical rails at the back? And then attach this to 2 cemented posts in the ground? Or some kind of post supports? And how big should those supporting posts be? It's going to be solid, so have to make sure it's not going to budge while we're enjoying a nice shower in the backyard! 

Thanks for your advice. 

JacobZ

Hi @adapants,

Thank you for your question about building a shower frame for your backyard.

At the width you are proposing, you can simply concrete in your two posts and screw some timbers to the front of the posts. At that span, with 120mm boards running horizontally, you won't have any issues with sagging so you shouldn't need vertical support between the posts.

The hardwood fence posts will be great for this, but for them to be sturdy while freestanding, the rule of thumb is that one-third the height of the timber that is out of the ground should be beneath the ground. In your situation, posts that are roughly 2m out of the ground should have 660mm concreted into the ground. You can round this down to 600mm for simplicity's sake.

You can hire a Post Hole Digger with a 300mm auger to dig your holes and speed up the process. With holes of this size, you'll need about 4x20kg bags of concrete per post.

Check out How to Set a Post for some guidance with your posts. You'll need a spirit level and a method of bracing your posts plumb in both directions while the concrete is setting. Star pickets driven into the earth with framing pine attached to both the post and star pickets is a good option for bracing.

If you're planning to use the same hardwood as your posts for your horizontals, you'll need some pretty solid screws. These Bremick XTP 14g x 150mm T40 Stainless Steel 316 Bugle Batten are a good option as they are made of stainless steel which is fine for use in constantly wet areas and at 150mm long, they will be embedded 75mm in your posts, giving a very strong connection. You'll need to use 4 screws per horizontal board. Use clamps to hold them in place while using a Sutton Tools 5.0mm Long Series Jobber Drill Bit to predrill pilot holes.

Let me know what you think and if you have further questions, please don't hesitate to ask.

Jacob