Build a Handrail Yourself With Tube Clamp Fittings
Build a handrail yourself with tube clamp fittings – guide, dimensions and parts list
A railing made of tube and tube clamp fittings does not need to be welded. You push the tubes into the fittings in hot-dip galvanised malleable cast iron and tighten the stainless steel grub screw supplied with an Allen key – the screw cuts itself into the tube and holds the joint permanently. No welding set, no pre-drilling, no rework on the corrosion protection. This guide shows step by step how to plan and build a railing for a balcony, terrace, staircase or works site.
First things first: dimensions and regulations
Before you order material, settle the height. The requirements are not set out in DIN 18065 alone but above all in the building code of your federal state – the figures differ from state to state.
| Parameter | Usual value | Note |
|---|---|---|
| Railing height up to a drop of 12 m | 90 cm | Bavaria, Brandenburg and Bremen require 110 cm; Baden-Württemberg allows 80 cm |
| Railing height above a drop of 12 m | 110 cm | applies nationwide as a minimum dimension |
| Clear spacing between infill bars | max. 12 cm | child safety – measured in one direction |
| Handrail height on stairs | approx. 90 cm above the step nosing | measured vertically above the nosing |
| Post spacing | 1.0 to 1.5 m | the closer, the stiffer the structure |
Important: these values are guidance, not legal advice. For fall protection on buildings, commercially used areas and public spaces, check the applicable state building code or ask your local building authority. Workplaces are additionally subject to the rules of the employers' liability insurance association.
Choosing the tube diameter
Tube clamp fittings are available for six common tube sizes. The diameter determines appearance, stiffness and price:
| Tube Ø | Imperial | Type | Typical use |
|---|---|---|---|
| 21.3 mm | 1/2" | T21 | Infill bars, light barriers |
| 26.9 mm | 3/4" | A27 | Infills, indoor handrails |
| 33.7 mm | 1" | B34 | Handrails, light railings |
| 42.4 mm | 1 1/4" | C42 | The standard in railing construction – a good balance of grip and stability |
| 48.3 mm | 1 1/2" | D48 | Posts for larger spans, industrial railings |
| 60.3 mm | 2" | E60 | Heavy structures, impact protection |
For a normal balcony or terrace railing you will do best with Ø 42.4 mm for posts and handrail. If you want to separate posts and handrail visually, combine Ø 48.3 mm posts with a Ø 42.4 mm handrail – there are reducing fittings that join the two sizes directly.
Parts list for a straight railing
Example: a 4 m long terrace railing, 90 cm high, post spacing 1.3 m, Ø 42.4 mm. You need 4 posts (each 90 cm plus the seating dimension) and one continuous handrail.
| Qty | Component | Item | Function |
|---|---|---|---|
| 4 | Oval base flange | 132C42 | Bolt the post to concrete or timber |
| 2 | Elbow 90° | 125C42 | Take the handrail down at the start and the end |
| 2 | Short tee | 101C42 | Intermediate post to the continuous handrail |
| 1 | Round wall flange | 131C42 | Terminate the handrail against the house wall |
| 4 | Plastic plug | 133C42 | Close off open tube ends |
| approx. 9 m | Steel tube Ø 42.4 mm, hot-dip galvanised | – | Posts, handrail, knee rail |
The matching stainless steel grub screws are supplied with every tube clamp fitting. You can order them separately as replacements or for modifications.
Assembly in seven steps
- Measure up. Measure the length of the railing run and mark the post positions. Start at the corners and divide the spaces evenly – that way the spacing stays the same throughout and the railing looks calm.
- Cut the tubes to length. Bring them to size with a tube cutter or hacksaw and remove the burr inside and out. For the handrail, allow for the insertion depth of the fittings.
- Protect the cut edges. Every cut exposes bare steel. Treat the edges with zinc spray, otherwise the tube will start to rust in exactly that spot – the most common mistake with outdoor railings.
- Set the base flanges. Align the base flanges and anchor them in the substrate with suitable fixings. Use heavy-duty anchors in concrete; in timber joists use through screws into load-bearing members.
- Stand the posts. Push the post tubes into the base flanges, plumb them with a spirit level and tighten the grub screws. Set all the posts roughly first, then fine-adjust them together.
- Fit the handrail. Push the fittings onto the posts, lay in the handrail tube, check the alignment, then tighten all the screws. The handrail pulls the structure together and gives it its final stiffness.
- Check. Retighten all grub screws, check the height and the infill bar spacing, and close off open tube ends with plugs.
Stair railings: the difference
On a staircase the handrail runs at an angle. Rigid 90° fittings do not work there. You need components that adapt to the pitch angle:
- Adjustable elbow 0–11° (154C42) – for the transition from the horizontal to the rising handrail on shallow stairs
- Oval base flange with 0–11° slope (152C42) – sets the post vertically on the sloping step
- Short tee 30–60° (129C42) – connects post and sloping handrail at common stair pitches
- Adjustable angle swivel (148C42) – freely adjustable for special angles
- Handrail bracket (143C42) – for the second handrail on the wall side
Measure the pitch angle of your staircase before you order. Between 30 and 60° you work with the tee 129, below that with the adjustable components of the 152 to 155 series.
Why hot-dip galvanised malleable cast iron
Malleable cast iron is tougher than ordinary cast iron – it does not fracture in a brittle way but deforms under overload. For a component that holds a guardrail together, that is the decisive difference. Hot-dip galvanising forms a metallurgically bonded zinc layer that holds even on edges and protects outdoors for decades. Additional electro-galvanising gives an even, smooth surface.
The screws are stainless steel 304 (V2A). That is not a minor detail: outdoors, a galvanised screw in a galvanised fitting is the first thing to seize – and it then shears off when you retighten or dismantle it.
Frequently asked questions
Do I have to weld to build a railing from tube clamp fittings?
No. The tubes are pushed in and clamped with the stainless steel grub screw supplied. All you need is an Allen key, a tube cutter and a drill for the base flanges.
Which tube diameter should I use for a balcony railing?
Ø 42.4 mm (1 1/4") is the standard: strong enough for common spans and comfortable to grip as a handrail. For post spacings over 1.5 m or in commercial settings, Ø 48.3 mm is the better choice.
How high does a railing have to be?
In most federal states 90 cm up to a drop of 12 m, and 110 cm above that. Bavaria, Brandenburg and Bremen already require 110 cm below 12 m. What governs is the state building code.
Can I dismantle the railing again?
Yes. The grub screw leaves a small indentation in the tube, but the joint can be released and re-made elsewhere. That is the advantage over a welded structure – particularly for rented premises or temporary barriers.
Will the fittings last outdoors?
Yes, hot-dip galvanised malleable cast iron is made for outdoor use. What matters is that you re-galvanise the cut edges of the tubes and close off open tube ends with plugs so that no water stands in the tube.
Matching material
- All tube clamp fittings for Ø 42.4 mm (1 1/4")
- All tube clamp fittings for Ø 48.3 mm (1 1/2")
- Tees · Elbows · Base flanges · Handrail brackets · Wall flanges
Not sure which parts you need for your project? Give us a call – we will go through the design with you and put the parts list together.