The Hyde Park Chapel is a working place of worship and visitor centre on one of the busiest streets in South Kensington, next to Princes Gate Mews. The entrance terrace sits above pavement level, reached by a long ramp at one end and a flight of stone steps at the other, and the whole of that edge needed guarding.
The entrance was designed for a horizontal line load of 1.5 kN/m, roughly double the figure used on a house. So this is our System 1 balustrade built to 1.5 kN/m, the commercial version of the standard System 1 that goes on most balconies and terraces. Same glass. Different metalwork, and on this job one part of it had to be made, because nobody sells it.
Surveyed, made in our Sheffield workshop and installed by us in June 2012.
Project overview
- Client type: Place of worship and visitor centre
- Location: Hyde Park Chapel, South Kensington, London SW7
- Scope: Survey, supply and installation
- Product: System 1 glass balustrade built to 1.5 kN/m, now priced online by the metre
- Design loading: 1.5 kN/m horizontal line load, to our structural engineer's calculation
- Posts: Heavier wall tube, set at reduced centres
- Post tops: Custom made and welded in house to take a 20mm stem, because the proprietary connector is only made with a 12mm one
- Glass: 10mm toughened clear, unchanged from the standard build
- Also supplied: Raking handrails to the entrance steps, and handrail to the ramp
- Material: 316 stainless steel, satin brushed
- Fabrication: BS EN 1090-2, UKCA marked
Get a price for something similar
The balustrade on this job is a product you can price yourself. System 1 built to a 1.5 kN/m commercial line load, by the metre, with the length, corners and fixing detail priced in.
0.36, 0.74, 1.5: the number that decides the job
Almost every balustrade enquiry we take is domestic, and domestic has two figures. Inside a house, stairs and landings are designed for a horizontal line load of 0.36 kN/m. Outside, on a balcony, a terrace or the edge of a raised patio, it is 0.74 kN/m. Those are the numbers on most of the project pages on this site.
Outside a dwelling it works differently, and this is where people go wrong. There is no inside and outside split. The figure comes from what the space is used for. Offices, classrooms, and the stairs, landings and corridors of institutional buildings sit at 0.74 kN/m. Restaurants and bars, retail, fixed seating within 530mm of the barrier and pedestrian areas in car parks are 1.5 kN/m. Assembly areas proper, theatres, cinemas and shopping malls are 3.0 kN/m, and grandstands and stadia are set by the local certifying authority rather than by a table.
One building can carry more than one figure. A school is a good example: the corridors and the classroom stairs are one number and the dining hall is another. Our BS 6180 barrier loadings guide has the full table.
The decision is not ours to make. The category comes from the building and its use, and it is set by the project's designer and agreed with building control. On this one the figure given to us was 1.5 kN/m, and that is what the balustrade was built to.
It is worth asking the question early. A balustrade quoted on a domestic assumption and then told it is a 1.5 kN/m job is not a balustrade with a bit added. It is a different piece of metalwork, and it is priced as a different product.
What changes when the line load doubles
The thing people expect to change is the glass. It is not.
On a posted balustrade the horizontal load is applied along the top of the handrail. It runs along the rail, crosses into the top of each post through the connector, travels down the post as a bending moment, and goes out through the base fixing. The glass sits between the posts as infill.
So the changes on this job are all in that load path.
Heavier wall posts. A balustrade post is a cantilever with the load applied at the top of it, so what matters is how much bending it will take. A thicker wall on the tube puts more metal where the stress is.
Smaller post centres. One change, two gains. Each post takes a smaller share of the load along the run, and the handrail spans less between supports.
Post tops that had to be made. That one needs a section of its own.
Where the catalogue runs out
The connector between a handrail and the top of a post is normally a proprietary fitting. You order it, it arrives, it works. The stem on it, which is the part actually carrying the load out of the rail and into the post, is 12mm in diameter.
At 1.5 kN/m that is not enough. Our structural engineer ran the calculation and specified 20mm, and at that size the fitting does not exist. Nobody makes one, because almost nobody needs one.
So the post tops on this job were made rather than bought: fabricated and welded in our own workshop, sized to the calculation rather than to what a supplier had on a shelf.
That is the practical difference between a balustrade supplier and a fabricator. A supplier can sell you the system right up to the point the catalogue covers, and this job was past that point. The glass did not change and the clamps did not change. The one part that had to change could only be made, and that is why it ended up as a product in its own right rather than a box to tick on the standard one.
Why the glass stayed at 10mm
10mm toughened clear, which is exactly what it would have been on a domestic job.
Infill glass is designed for the loads applied to the panel itself, not for the line load running along the top of the barrier, so it does not scale with the building category the way the metalwork does. People assume a heavier duty balustrade means heavier glass and it is usually the wrong place to look.
The ramp and the steps
Guarding the terrace edge is only part of what an entrance like this needs. People have to get up to it, and on a public building that means two routes: steps for most visitors and a ramp for anyone who cannot use them.
The steps are not a straight flight. They fan out from the doors in a shallow curve, each tread a little longer than the one above it, with tactile studs set into the stone. The balustrade follows that curve as a run of flat panels set at an angle to each other, and the handrail is bent to the radius so it stays a smooth line under the hand. Work like this is set out from the survey rather than from standard panel widths.
Both routes got handrails. On the flight the rail follows the pitch line of the steps and the height is taken from the nosings. On the ramp it follows the gradient and the height comes off the ramp surface. Where the two arrive at the same terrace, the heights have to agree.
Part M, which covers access into a building, asks more of a public entrance than Part K does of a private stair: continuous rails, graspable sections, and extensions beyond the top and bottom of a flight. We build to whatever the project is working to, and our handrail building regulations guide sets out the difference. What a particular building has to satisfy is confirmed by its designer, its access consultant and building control, not by us.
Why stainless, on this building
The chapel is faced in pale stone on a main road through central London, and the balustrade runs the length of the frontage at eye level to everyone walking past.
Satin brushed 316 stainless suits that better than a painted finish would. There is no coating to chip or flake, it washes rather than needing repainting, and brushed hides handling marks in a way a mirror polish does not, which matters on a rail hundreds of visitors touch.
316 rather than 304 is our standard on external work. The difference is molybdenum, which resists chloride pitting, and a street frontage in central London gets winter road salt and traffic grime all year.
Fourteen years on
This one went in during June 2012. We went back in 2026 and took a photograph on the same steps. The handrail, the posts and the glass are the ones we installed.
A public entrance does not get an easy life. Everybody who visits the building touches that rail, and it stands on a main road through central London taking winter salt and traffic grime all year. It is the best argument we can make for 316 stainless on a building like this, and it is a photograph rather than a claim.
Get a price for something similar
The balustrade on this job is priced online by the metre, so you can work out a figure before you speak to anyone. If you would rather we did it, send drawings, or photographs and the length of each run, to sales@diomet.co.uk, or call 0114 243 9009. On a commercial building, tell us the design line load, or who is deciding it.
- System 1 glass balustrade built to 1.5 kN/m, the balustrade on this job, priced online by the metre
- Standard System 1 stainless steel glass balustrade, where the building is domestic and 0.74 kN/m applies
- Stainless steel access handrail for steps and ramps, the handrails on the entrance route
- Stainless steel handrail on posts, where a rail is wanted without guarding
- System 3 stainless steel wire rope balustrade, another option on a public building
- Metal railings, where painted steel infill suits the building better than glass
If you are not sure what to send, our how to get a price page sets it out.
Before you order
- BS 6180 barrier and balustrade loadings
- Glass balustrade building regulations
- Handrail building regulations
- Our certification and what it covers
- Material finishes
- Installation
- Looking after stainless steel outdoors
Frequently asked questions
What is a 1.5 kN/m balustrade?
One designed for a horizontal line load of 1.5 kN/m along the handrail. In the loading tables that figure covers restaurants and bars, retail areas, fixed seating within 530mm of the barrier and pedestrian areas in car parks, and it is also a figure a designer may arrive at on a commercial entrance like this one. Domestic external guarding is normally 0.74 kN/m, so it is roughly double.
Does a higher loading mean thicker glass?
Not usually, and that catches people out. On a posted system the posts and the handrail carry the line load and the glass is infill between them. What changes is the metalwork.
Can you buy a 1.5 kN/m balustrade off the shelf?
Not as a kit from a balustrade supplier. The proprietary handrail to post connector has a 12mm stem, and at this loading the calculation called for 20mm, and connectors are not made at that size. We make the post tops ourselves, which is why we can sell it as a standard product: our 1.5 kN/m System 1 is priced online by the metre, the same way the domestic one is.
What does a 1.5 kN/m balustrade cost?
It is priced by the metre on the product page, with the length, the number of corners and the fixing detail all in the price. Stairs, raked runs and curved sections like the ones on this job are quoted individually.
What actually changed on this job?
Three things: heavier wall posts, smaller post centres, and custom made post tops to take a 20mm stem. All three are in the path the load takes from the handrail down into the base fixing.
Can a glass balustrade follow curved steps?
Yes. The glass is made as flat panels set at an angle to each other so the run follows the curve, and the handrail is bent to the radius. It is set out from a survey rather than from standard panel widths.
Who decides which loading applies?
The project's designer, against the building's use category, and agreed with building control. We build to the figure we are given, have it checked by our structural engineer, and issue a declaration of performance for the steelwork. It is not a decision we take on anyone's behalf.
Do you work on public and commercial buildings?
Yes. Places of worship, schools, council buildings, care settings and commercial premises, surveyed, made in Sheffield and installed by our own fitters.