Knightsbridge Penthouse: A Hardwood Decking Terrace Above London
Designing and building a hardwood decking terrace in Ipe (often called Brazilian walnut) is about as close as you get to pure decking theatre. High above Knightsbridge, this penthouse project asked for exactly that: a calm, luxurious outdoor room that felt every bit as refined as the interior.
Karl Harrison, London’s trusted decking designer since 2003, was commissioned to turn a narrow city terrace into a long-lasting statement in timber, metal and light.
A brief for quiet luxury
The client wanted the terrace to echo the apartment: elegant, minimalist and obsessively detailed. No fuss, no visible fixings, no compromise on quality. Every line had to be straight, every junction deliberate, and every material able to stand up to London’s weather as well as London’s skyline.
Karl’s solution was an Ipe hardwood deck, custom-made for this project alone. The boards present a visible face width of 144 mm with a precise 4 mm gap between each one. Each board length was set at 4306 mm so the terrace reads as clean, continuous planks rather than a patchwork of short pieces.
Craftsmanship in every board
This terrace is all about craftsmanship you can feel underfoot. The structure was designed and built by Karl’s in-house team, “Decking by Karl”, who specialise in complex, high-value decks across London.
The Brazilian walnut boards are fixed with a concealed system, so there are no screw heads to interrupt the grain. Instead, your eye follows long, uninterrupted runs of timber from the bronze floor plates at the threshold, right out towards the view. The geometry of the decking aligns with the building, the glazing and the planters, giving the whole space a composed, architectural feel.
Because this is a penthouse, accuracy really matters. Levels, falls and edges were set out to tight tolerances so that water drains correctly while the deck still feels perfectly level to walk on.
Bronze details that elevate the design
Bronze is the quiet hero of this terrace. Custom floor plates lead you out from the interior onto the deck. From there, bronze returns on the planters, creating a continuous language of warm metal against the rich brown of the Ipe.
A bespoke bronze balustrade runs along the edge of the terrace. It feels solid yet light, framing the view rather than blocking it. The pairing of natural hardwood and patinated metal gives the space a timeless quality – modern, but not fashionable in a way that will date.
Lighting the London skyline
Subtle lighting was essential. The terrace comes alive after dark, when carefully positioned fittings wash the planters, highlight the balustrade and pick up the texture of the boards. The aim was not to flood the space with light, but to give just enough glow for evening drinks, quiet conversation and those moments when the city feels almost still.
Why Ipe hardwood for a London deck?
Ipe is one of the most durable timbers available. This project uses FSC-certified Brazilian walnut, specified to deliver a service life of 60+ years when properly designed and built. In a premium setting like Knightsbridge, that longevity matters.
You can maintain Ipe to keep its deep chocolate colour using a professional system such as Owatrol’s decking cleaners and oils. Or you can let nature take over and enjoy the slow shift to a soft silver grey. Either way, the structure beneath stays strong.
Designed, supplied and built by “Decking by Karl”
From first survey to the final clean-down, the project was handled by Karl and his employed team. That single point of responsibility meant the design intent was protected at every stage:
- Detailed site survey and structural design
- Bespoke Ipe specification and supply
- Precision installation with hidden fixings
- Bronze detailing, lighting and finishing touches
Karl has been designing decking structures and outdoor platforms since 2003, with projects across London and the Home Counties. Penthouses like this Knightsbridge terrace show the level of trust clients place in his work.
Thinking about your own London terrace?
If your apartment, townhouse or penthouse needs a hardwood decking terrace that feels as considered as your interior, Karl Harrison can help. He combines technical expertise with a designer’s eye, creating decks that are beautiful, safe and built to last.
To discuss a new decking project in London – or to book a design consultation – contact Karl Harrison and discover what a carefully designed hardwood terrace could do for your home.
