How to add under house screening to metal posts?

[Nonithepony]

Hi, I am new to DIY, I wish to add screening under my house, thinking of just vertical wooden palings on a couple horizontal pieces, but how do I attach the horizontal pieces to the metal stumps supporting my house? thank you.

[EricL]

Hello @Nonithepony

Welcome to the Bunnings Workshop community. It's fabulous to have you join us, and thank you for sharing your question about adding under house screening to metal posts.

Is this house a brand new build? I only ask because that would mean that the builder's warranty is still in effect. We don't want to do anything that might void this warranty by accidentally adding a structure that might compromise your house warranty. You'll notice that there is a cement barrier on the footing of your house. Normally each post would just have an ordinary square cement base for the metal post to sit in. 

But not in this situation, the concrete actually travels from post to post. In fact, it goes all the way around the house. It acts as a barrier of sorts underground. Just to be safe I don't recommend tampering with that barrier. Traditionally putting up a screen under the house would have been straightforward as the posts were made of timber.

In this instance, I recommend building a timber frame around the metal posts in order for you to attach the timber rails and create your screening. I suggest that the frame be at least 100mm off the ground and 100mm away from the bottom of the house. This is to prevent any chance of termites travelling along the length of the timber to your house.

I suggest using H4 timber in building the frame. This is a bit over the top but it will prevent the timber from rotting and is protected against termite attack. The only timber piece that will be very close to the ground is the centre support. This post is necessary to support the rails as the distance between the metal posts is too wide. I suggest using TuffBlock 300 x 300 x 90mm Instant Foundation System Deck Support as the footing for the centre support post.

However, please note before you begin, I suggest speaking to your former builder and asking them if there was a screening plan in place. This will at least guarantee that the screen you build is in accordance with the builder's original plan. It is also important to ask if building the screen will void your builder's warranty. I've placed an example of how the timber frame might be built.

Let me tag our experienced members @Adam_W and @diy_hausdesigns for their recommendations.

If you have any other questions we can help with, please let us know.

Eric

[Adam_W]

Hi @Nonithepony & welcome!

I’ve recently done what I think it is you’re wanting to do. 
Rather than trying to explain I’ll take some photos for you tomorrow & post them.  

[MitchellMc]

Hi @Nonithepony,

It's excellent to see that @EricL and @Adam_W have been assisting. Let me point you to @Adam_W's amazing step-by-step article on How to build timber screening. I trust you'll find it exceptionally helpful with this project.

Keep us updated, and reach out if you need further assistance.

Mitchell

[Adam_W]

Hi again @Nonithepony 

Okay, as @MitchellMc suggested have a look at my screening project & video as that uses the same sort of techniques as those I used to do what is in these photos...
We recently renovated & the original builder (20-years ago) had put screening around the posts so I followed their technique.
Pretty simple but does require some power tools.

To each post you need to attach a timber batten (I'll call it a post batten) flush with the post front and the wider side of the timber against the post. Timber needs to be H3 minimum, I found 70 x 35 was a good size.
It's worth putting a stringline on your posts from one end of the area to the other first as posts may not be 100% aligned. You won't notice this to look at them but you will see a bowing in & out once you put screening on them. If they are not accurately aligned then you'll need to use the stringline to guide you to position the post battens correctly.
To attach the post battens you'll need to use metal screws of suitable length. With a 35mm batten then 50mm screws will be fine. Here's an example of the sort you'll need.

You will need to clamp the battens in place on the posts and then pre-drill both the timber and the metal post. These screws are supposedly self-drilling but they rarely self-drill. Most of the time the tip just burns out so pre-drilling is essential or you'll be throwing a lot of screws away.
Once you have all of the post battens on you can add the actual slats. If you don't have a nail gun then I'd recommend that you screw them on.
Once you have all of the slats on you need to add a floating batten, just use a piece of the slat timber, to the centre or each span (i.e. the gap between posts). This stops bowing and movement. Depending on the lengths of your slats you may also need to use floating battens as joiners between slat lengths.

Does this all sort of make sense?
You will need a reasonably good quality drill-driver & a couple of heavy-duty bar clamps for the project.

From the yardBatten attached to postsFloating batten to stop bowing.

[Nonithepony]

Thank you so much, this is incredibly helpful!

[Nonithepony]

thank you very much Eric, I can say the house isn’t new at all, but was restumped from the old wood to these metal posts within the last 5 years. The ground is soft in my area so maybe the concrete is for increased stability, I’m not sure. The info you and other responders gave is invaluable tho, I really appreciate it.

[EricL]

Hi @Nonithepony

I'm glad the information we provided was helpful. Any updates you can provide while building the screen would be much appreciated. I'm sure our members would be very keen to see how you put the screen together.

If you have any other questions we can help with, please let us know.

Eric