Glass Balustrade FAQs

The questions we get asked most about glass balustrades, answered briefly. If you want the reasoning behind the choices, that is in our glass balustrade buying guide, and the rules are in our glass balustrade building regulations guide.

Buying and cost

How much does a glass balustrade cost?

Balustrades are priced by the metre, in bands. Add every leg of the run together, round up to the next whole metre, then pick that band on the system you want. The price you see on the page is for that length of balustrade as a kit, and the dropdowns show what each option adds.

Two things then move the figure more than anything else: the finish, and whether the run turns any corners. Delivery is quoted separately once we know the length and where it is going.

Which is your cheapest balustrade?

System 9, galvanised steel and glass with no powder coating. It is the same structural job as the painted systems with the cosmetic step left off, which is exactly why it costs less. For a low level patio screen that is not guarding a drop, System 11 is cheaper again, but it is not a barrier and should not be used as one.

What makes a balustrade expensive?

In order: frameless rather than framed, because the glass gets much thicker and has to do structural work; stainless rather than painted steel, and mirror polished rather than satin; corners, because each change of direction adds components; and height, where a privacy screen at 1,800mm is a different animal from a 1,100mm barrier.

What does not move it much is an extra half metre of length. If you are trying to save money, look at the finish and the frameless decision first.

How long does a balustrade take to make?

Everything is made to order and the clock starts at drawing sign-off rather than at the order, so a firm lead time comes with your quotation. Glass carries its own lead time on top of the steelwork, and frosted, tinted or thicker laminated panels take longer than clear toughened. Ask before you book a fitter.

Choosing a system

Framed or frameless?

A framed system has steel or stainless posts with glass clamped between them. The posts do the structural work and the glass is infill. A frameless system has no posts and the glass itself is the barrier.

Framed is the more forgiving choice. It fixes to almost anything, it copes with an opening that is slightly out of square, it works on stairs, and it is realistic as a self install job. Frameless gives the cleaner line but it needs a flat, solid, structurally sound fixing surface, the glass is much heavier, and we would always recommend having it installed. There is 25 metres of it with no handrail at all on our frameless infinity balustrade in Ranmoor.

Do I need a handrail?

On a staircase, yes. Approved Document K requires a continuous handrail, although it does not have to be on the glass side: a wall rail on the opposite side satisfies it, which is how frameless glass ends up on stairs with no top rail.

On a balcony, terrace or landing a handrail is not strictly required provided the barrier meets the height and loading requirements. It does change the glass, though, which is the part people miss. See the next answer.

Toughened or laminated glass?

It follows from the handrail. With a continuous handrail across the top, toughened glass is acceptable, because the rail still guards the edge if a pane is ever broken. With no handrail on the glass, it has to be laminated, because the glass is the whole barrier and has to stay in place after an impact. Our coastal lodge balustrade at Cardoness is the worked example, on a site where the lodges either side had been done in plain toughened.

Two things decide it: whether the posts or the glass are carrying the load, and whether there is a handrail over the top. Post supported is 10mm or 12mm toughened with a rail, and 13.5mm laminated outside where there is no rail. Frameless in a base channel, such as System 4, is 12mm toughened with a rail or 13.5mm laminated without internally, and 15mm or 17.5mm externally. Frameless side fixed, such as System 7, is 15mm with a rail and 17.5mm without, inside as well as out, because the pane is taller and the extra leverage puts more bending force into the glass. 21.5mm on longer spans and commercial work. The rule behind it is simple: with a rail over the top the glass can be toughened, because the rail still guards the edge if a pane is broken. With no rail it has to be laminated, because the glass is the barrier on its own. All balustrade glass is safety glass tested to BS EN 12600. More on the two processes in our toughened and laminated glass guide.

Which system suits a parapet or cavity wall?

Our parapet and cavity wall balustrade, which is designed for exactly this and clamps the wall rather than relying on the depth of a single skin.

This is the single most common problem we find on site. A side fixed balustrade bolted into the outer skin of a cavity wall may have very little solid material behind it. If you are fixing to a parapet, a coping or a thin skin, send us a photograph before you order anything. See how it goes together on our parapet cavity wall balustrade in Oxford.

Can I have it in a colour?

Yes, any RAL colour at no extra cost on the powdercoated systems, and there is nothing to pick at checkout. Anthracite grey RAL 7016 is by far the most asked for. Tell us the reference when we contact you about your drawing, and send a photo if you are matching existing windows.

Can I have frosted or tinted glass, or a privacy screen?

Yes to all three. Frosted and tinted glass are available on any system, priced on request rather than from the dropdown, so ask before you order rather than after. There is a tinted example on our tinted grey balustrade and gate near Barnsley.

Privacy screens are a different item. They are usually required at 1,800mm high in obscured glass on the sides facing neighbours, and they turn up as a planning condition more often than people expect. At that height the post design, glass specification and wind loading all change, so factor them in from the start rather than retrofitting them. We make them bespoke to match the balustrade.

Measuring and fitting

How do I measure my run?

Add every leg together and round up to the next whole metre, then count the changes of direction. A straight run has no corners, an L shape has one, a U shape around three sides has two. The size bands are price bands, not fixed sizes: a 3.75 metre run is ordered as up to 4 metres and we still make it to your exact dimensions.

Does it arrive assembled?

No, and that is deliberate. Posts come fully made up with the clamps already fitted and the handrails pre-drilled, but the balustrade arrives in pieces and bolts together on site. That is what gets a balustrade through a house, round a side return or up onto a roof terrace.

Can I fit it myself?

On a framed, base plate fixed system, yes, and plenty of people do. Position the posts, drill and bolt them down, drop the glass in, tighten the clamps, connect the handrail. A competent DIYer with a drill and a level can manage it, and full instructions come with it.

We would steer you towards professional installation for anything frameless, anything core drilled, and stairs with turns or winders.

Are the fixings supplied?

Every fixing needed to assemble the balustrade is supplied with it. Wall and floor fixings are not, on a supply only order. The right anchor depends on what your building is made of and what condition it is in, and that is not a call we can make from here. Fixing points come drilled ready and your installer picks anchors to suit. Where we install, we make that decision on site and provide them.

What can I fix it to?

  • Timber decking. Base plate fixed, bolting through into the joists rather than just the boards
  • Concrete and paving. Base plate fixed with anchor bolts, the most straightforward of the lot
  • Composite decking. Base plate fixed, but through the boards into the subframe beneath. Composite boards on their own have nothing like enough pull-out strength
  • Existing steelwork. Bolted or welded, common on a steel framed balcony
  • Brick retaining walls and raised patios. Core drilled and grouted in rather than bolted to the top course, which is where the wall is weakest. See our core drilled balustrade in Dronfield
  • Parapets and cavity walls. See above, and send a photograph first

Do you survey, and do you install?

We survey, and a site survey is a chargeable visit in its own right rather than a free sales call. It is usually money well spent where the balustrade has to meet an existing wall, parapet or stair.

We install nationwide with our own site teams rather than subcontractors, and installation is quoted separately from the steelwork so you can see both figures. We do not make good afterwards unless it has been quoted, because we are fabricators rather than general builders.

Finish and durability

Is 304 or 316 stainless right for my job?

G304 internally only. G316 for anything external, and it is not optional. Stainless relies on a thin oxide layer for its corrosion resistance, and chlorides attack that layer. G316 has a higher molybdenum content and stands up to it far better.

Worth saying plainly: stainless steel is stainless, not stainfree. Even G316 wants regular cleaning outdoors. Soapy water is enough, about as often as you clean your windows. Neglect it and you get tea staining that is harder and dearer to put right later.

Satin or mirror polished?

Satin is the usual choice. The brushed texture hides fingerprints and light scratching well, but the grain can hold salt near the coast. Mirror polished is smooth and grain free, so it sheds salt better and is the lower maintenance option on a coastal property, but it shows fingerprints more readily. It is a genuine trade-off rather than one being better.

What finish should I use near the coast?

G316 stainless, mirror polished if the budget allows, or galvanised and powdercoated. Both work. Whichever you pick, commit to cleaning it regularly, because the sea will find anything you neglect.

How do I look after it?

Warm soapy water, more often near the coast or on a busy road. Glass and powder coating both want the same. See our product maintenance guide.

Regulations and certification

How high does a glass balustrade have to be?

In a house, 900mm on stairs, landings, ramps and the edges of internal floors, measured from the pitch line on a flight and from finished floor level everywhere else. 1,100mm on external balconies, terraces and roof edges. In a building other than a dwelling the stairs stay at 900mm and every other position, internal landings included, goes to 1,100mm. Guarding is required wherever there is a change in level of more than 600mm in a dwelling.

If your floor finish is not down yet, tell us the build-up you are planning, because it moves the measurement.

What is the 100mm sphere rule?

No opening in the balustrade may allow a 100mm sphere to pass through. It is a child safety requirement. Solid glass panels are not the issue; the gaps between panels, between glass and posts, and under the bottom of the glass are. It is also why glass on a flight of steps is stepped rather than raked, which is set out on our framed glass balustrade to stone steps in Grenoside.

What loading does it have to take?

BS 6180 sets a horizontal line load at the top of the barrier: 0.36 kN/m internally for stairs, landings and mezzanines, and 0.74 kN/m externally for balconies, terraces and raised decking. General commercial and assembly work, including communal areas in flats, is 1.5 kN/m, and areas subject to crowd loading such as stadium terraces are 3.0 kN/m. Tell us if it is for a commercial or public building so we specify the right loading rather than the domestic one.

Do I need building control, or planning permission?

Building control, usually yes, if the balustrade forms part of works subject to the regulations. They will generally want to see a UKCA Declaration of Performance for the steelwork. Replacing an existing balustrade still has to meet current standards, not the ones in force when the original went in.

Planning permission, usually not. Adding or replacing a balustrade on an existing structure is normally permitted development. You may need it if you are building a new balcony, your property is listed, or you are in a conservation area.

Is your balustrade UKCA marked?

Yes, and it is a legal requirement rather than a badge. The posts, frames and base plates are structural steelwork, so they have to be made under a certified factory production control system and carry the UKCA mark. We are certified to BS EN 1090-2 with coded welders and calibrated equipment, and a Declaration of Performance comes as standard. More on what that covers on our UKCA certification page.

A great deal of imported balustrade steelwork arrives with no marking at all. Ask any supplier to confirm BS EN 1090 certification before you order, because that certificate is the document your building control officer will ask for.

Do you provide structural calculations?

We can, but they are a separate piece of work, always chargeable individually and never included in the price on a product page. If you know calculations will be asked for, say so at enquiry and we will price them alongside the balustrade.

Is there a guarantee?

Ten years on the steelwork we manufacture, covering any defect attributable to a manufacturing, assembly or material fault. Parts and labour for the first twelve months, parts for the remaining nine years. Glass is not covered by the warranty, being a fragile material we buy in rather than make. Transit damage is a separate matter with its own 48 hour reporting window. Full wording on our terms and conditions page.

Where to buy

See it in use

Still not answered?

Send us the length of the run, what you are fixing to and a photograph, and we will tell you which system suits it and what it is likely to cost. Call 0114 243 9009 or email sales@diomet.co.uk. We have been fabricating in Sheffield for 35+ years and we deal with building control queries every week.

Worth reading next: the glass balustrade buying guide, the glass balustrade building regulations guide, the handrail building regulations guide, and our general FAQs.