How to build an outdoor stair handrail?

[julian27845]

Hi, I need to build a handrail for this staircase, there are lots of videos online but nothing seems to suit exactly what I have here in the photo below, and I also can't seem to find a product or kit which suits this as well, I'm thinking a couple of posts, then join them up with a few pieces of wood, would be good if there was a video or guide which I could follow though, any advice?

Cheers, Julian

[MitchellMc]

Hi @julian27845,

The easiest option would likely be to concrete in two posts at either end of the stairs. Bolt the upper post to the face of the retaining wall as well, or you could install the upper post behind the retaining wall in the top elevated section. From there, you'll have two solid mounting points, which a PEAK Aluminium Balustrade 1800mm Black Modular Handrail Kit can be fixed between. The maximum distance for that rail system between mounts is 1360mm, so if your posts are further than that, you might require a mid-post to close the gap.

Alternatively, with your three posts, you could construct a timber rail using a timber handrail, base rail, and balusters. To build a timber handrail, start by concreting in your two end posts at the bottom and top of the stairs. Bolt the upper post to the face of the retaining wall, if possible, or place it in the elevated section behind the wall for extra stability. Next, cut a timber bottom rail to fit between the posts and position it about 75-100mm above the stair tread, securing it to the posts with outdoor-rated screws or bolts to ensure it’s level and sturdy.

After the bottom rail is in place, cut baluster slats to fit between the bottom rail and where the handrail will be positioned, spacing them evenly at about 100mm apart. Attach each baluster to the bottom rail with screws, ensuring they’re plumb and aligned. Finally, cut your handrail to length and attach it to the tops of the posts, aligning it directly above the balusters. Secure each baluster to the handrail for added stability, and fasten the handrail firmly to each post.

I am unaware of any videos or guides on this subject, but I've created a rendering below for you to assist.

Please let me know if you have any questions.

Mitchell

[julian27845]

Thanks Mitchell, this is really useful, that diagram really helps me see how it will come together, how did you make this image?

I think I will do this with all wood, similar to the image, I was thinking of not using concrete and just nailing the posts and structure to the stairs / retaining wall, I don't have any experience with concrete so was going to avoid it if I could

Cheers, Julian

[MitchellMc]

The diagram is made with a program called Tinkercad, but there are other options out there @julian27845.

My preference would be to concrete the posts in and then screw them to the stairs/retaining wall. That will leave you with a much more solid handrail. By attaching the handrail posts only with screws, there could be some flex to the handrail. Concreting posts is really quite easy with no particular skill involved. Just dig yourself a 350 x 350 x 450mm deep hole, stick the post in, add a couple of props to stabilise it so it's straight (or screw it to the stairs/retaining wall), fill the hole with water and then add a bag or so of Quick set concrete.

Here's a helpful step-by-step guide: How to set a post.

Mitchell

[julian27845]

Hi Mitchell, just a few follow up questions:

I'm going to get two 90mm x 90mm posts (one 2.4m and one 3.6m), and cement them into the ground and also attach them to the existing stairs / retaining wall

1. What would be the best screws to use to attach the posts, both to the stairs and the retaining wall? i'm not used to attaching something 90mm thick to anything so not sure how to tackle that

2. The link to the cement didn't work, how much cement do you think I'll need and what's the name of the product? also I don't have a wheel barrow, is there something else I could pick up to mix the cement?

3. The soil around the job is mostly clay, was a massive effort to dig it all up, but now i have a bit of an issue of how do I put it back once I'm done, so a lot of the clay came up in clumps and if i toss it back in the ground it will have a lot of air inbetween that I need to flatten

Cheers, Julian

[JacobZ]

Hi @julian27845,

Thank you for the follow-up questions.

1. There are two options you can use, a galvanised bolt or a galvanised batten screw. 
   
   A bolt is better if you can use them, but you won't be able to use them on the retaining wall as you don't have access to the back side of the wall to attach a nut. I'd suggest where it is possible using M10 x 150mm Galvanised Cup Head Bolts & Nuts with an M10 38 x 38 x 3mm Galvanised Square Washer behind the nut. This will allow you to create more tension than a screw will.  
   
   Where you can't use a nut, you'll want to use galvanised batten screws that are long enough to go all the way through the post and embed in the stair stringers and retaining wall as far as possible without poking out the other side. Either these 125mm Class 3 Galvanised Bugle Batten Screws or these 150mm Class 3 Galvanised Bugle Batten Screws will work.
   
    
2. Any quick-set, rapid-set or post-mix concrete will work. Just make sure it says concrete, not cement. 
   
   Cement is a part of concrete, that is mixed with sand and aggregate. Cement alone will not be strong enough for this task. I'd suggest two bags of concrete per post.
   
   I have mixed concrete in these 60L Flexi Storage Tubs before. They are a good option if you don't have a wheelbarrow.
   
    
3. The holes will be filled with concrete, so the clay won't be going back into the holes. You can dispose of it however you like, but if you'd like to break it up, you can add a bag of Gypsum Clay Breaker to break it up.
    

Let me know if you have any further questions.

Jacob
 

[julian27845]

Hi @MitchellMc  and @JacobZ , just wanted to say thanks, I'm nearly finished, just ran out of wood for the middle and also need to add the top piece of the handrail, I'm pretty happy with it so appreciate the help.

I have one small problem, the lower post has some splitting, I did predrill a hole but i guess it wasn't big enough, or my timber screws were too large, it's ok for now, but just want to fix it up so that it won't get worse, should I get a screw and bolt it on the other side? which screw should I use? this is a 90mm post

Cheers, Julian

[Revitalize]

Hey Julian,

If your post is splitting you should drill a 10mm hole 2/3rds of the way up from the bottom of the split, then try to fill the crack with woodglue, I use the gorillas brand and it's very good, then use a 115x10mm or 120x10mm bolt with a nyloc nut and 1 washer on either side of the post and tighten it up until the wood glue starts to squeeze out.  That should hold it together and prevent it from splitting further.

After doing this you would just need to monitor the crack over time but it should fix it and allow you to keep that post.

[EricL]

Hello @Revitalize 

Let me tag @julian27845 to make them aware of your recommendation. Using a nut and bolt to hold the wood together in combination with wood glue is an excellent idea to prevent the wood from splitting further.

Thank you for sharing your knowledge and experience with the community.

Eric