Room Tour: A Giant Sash Window Opens Up a Double-height Space
The rear of this Georgian townhouse in London was dark and poorly connected to the garden. Now it feels bright and airy
The key social spaces on the ground and lower ground floors of this tall, skinny house were not fulfilling their potential. An existing, two-storey infill extension at the rear of the building in theory connected both floors to the garden – via a window upstairs and double doors out to the patio downstairs – but, in reality, the extension had scope to work way harder at this job.
The two areas – one containing a living space, the other containing the kitchen-diner – were also separated, as well as cramped and dark, especially for garden-facing spaces. As such, the layouts weren’t hugely conducive to socialising, a priority for the owner. Enter architect John Crowley of Anthro Architecture, who immediately identified a potential design game-changer.
The two areas – one containing a living space, the other containing the kitchen-diner – were also separated, as well as cramped and dark, especially for garden-facing spaces. As such, the layouts weren’t hugely conducive to socialising, a priority for the owner. Enter architect John Crowley of Anthro Architecture, who immediately identified a potential design game-changer.
A ‘before’ photo of the same space, taken from a slightly different angle, shows how narrow the room felt with the furniture orientated as it was. You also get a sense of how the staircase and a cloakroom (behind that wall on the right) were blocking space and making the area feel cramped.
“The sofa faced a loo and utility room hidden under the stairs,” John says. “These were taking up a lot of real estate. That’s why the stairs were an obvious game-changer.”
There was a narrow, double-height space at the end of this room. Glancing back at the first photo, you can see how much more light is flooding in now that the space has been widened.
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“The sofa faced a loo and utility room hidden under the stairs,” John says. “These were taking up a lot of real estate. That’s why the stairs were an obvious game-changer.”
There was a narrow, double-height space at the end of this room. Glancing back at the first photo, you can see how much more light is flooding in now that the space has been widened.
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In this original plan, you can see how the void above the now dining room didn’t fill the whole width of the house, as it does now. You can also better understand what John did with the staircase.
A plan of the lower ground floor as it is now.
The raised ground floor plan clearly illustrates the expanded width of the new double-height space.
Looking at the rear of the house before John’s redesign, you can see there was no access to the garden from the original, non-extension part of the house on the left.
“The existing sash window had to be retained as part of planning requirements, but what we managed to do was extend it to the ground, so it gives you secondary access to the garden and, when you come down the stairs, you now get this amazing tall vista,” John says.
At the back of this shot, you can see the side of the original staircase.
“The existing sash window had to be retained as part of planning requirements, but what we managed to do was extend it to the ground, so it gives you secondary access to the garden and, when you come down the stairs, you now get this amazing tall vista,” John says.
At the back of this shot, you can see the side of the original staircase.
The new extension takes up the same floor space as the old one, only now the new stairs point towards the garden and open directly into the extension’s upper and lower rooms, creating more space at each level. Previously, the staircase had also incorporated a turn, which John removed.
“We opened up the ground floor plan, then created a new staircase connecting directly into the lower ground, which created a double-height space to the rear facade,” he says. You can glimpse the new staircase, which finishes on a small landing, through the glazed door on the left.
The super-sized sash window makes a huge difference, too, creating a full opening to the garden in the way bifolds do, but without the need for additional floorspace for the stacked doors.
Sash window, IQ Glass.
“We opened up the ground floor plan, then created a new staircase connecting directly into the lower ground, which created a double-height space to the rear facade,” he says. You can glimpse the new staircase, which finishes on a small landing, through the glazed door on the left.
The super-sized sash window makes a huge difference, too, creating a full opening to the garden in the way bifolds do, but without the need for additional floorspace for the stacked doors.
Sash window, IQ Glass.
“They’re very rare,” John says of the sash. “It has hidden weights, so you can move it with your little finger. It took a serious amount of engineering and coordination with the glazing company to [make it] work.”
John also landscaped the garden. He chose the same grey limestone flooring for indoors as out, though inside it’s warmed by underfloor heating.
The bench facing the house creates a courtyard for people to spill out onto when the owner entertains. The upper terrace catches the sun.
John also landscaped the garden. He chose the same grey limestone flooring for indoors as out, though inside it’s warmed by underfloor heating.
The bench facing the house creates a courtyard for people to spill out onto when the owner entertains. The upper terrace catches the sun.
Here, you’d be standing on the lower landing of the new staircase.
The kitchen stretches towards the front of the house, where there’s now a cinema room (its TV screen is just visible here). The room behind the balcony above is a bar area and reception room.
Small details matter in architecture and here, notice the way the wall finish (polished plaster) and the wood panelling in the kitchen (European oak veneer) continue into the bar area above. The doors in the panelled sections even line up top and bottom.
“It helps with a visual connection across floors and so extends the space, making the kitchen almost appear taller,” John says. “Basement kitchens can feel low.”
The kitchen stretches towards the front of the house, where there’s now a cinema room (its TV screen is just visible here). The room behind the balcony above is a bar area and reception room.
Small details matter in architecture and here, notice the way the wall finish (polished plaster) and the wood panelling in the kitchen (European oak veneer) continue into the bar area above. The doors in the panelled sections even line up top and bottom.
“It helps with a visual connection across floors and so extends the space, making the kitchen almost appear taller,” John says. “Basement kitchens can feel low.”
Originally, the kitchen had been at the front of the lower ground floor, where the cinema room is now, which meant it wasn’t connected to the garden at all.
More: How to Start a Kitchen Renovation
More: How to Start a Kitchen Renovation
The Carrara marble worktop has curved corners and John highlights how important the choice of material was here.
“It gives the space more light by reflecting the ceiling, which is a massive and often unconsidered landscape in a basement. Ceiling is what you experience most in a basement, in fact.”
As such, there was a conscious decision not to have spotlights. “It would have broken the clean lines of the space,” he says.
The function of the kitchen is all on the left and in the island. Closest is a fridge-freezer, then pantry storage, pan drawers and cutlery storage beneath a zoneless induction hob, then double ovens. At the far end, there’s tall storage for crockery and other dining items. The island houses a dishwasher and bins.
All kitchen fittings, including an KM7678FL induction hob, Miele.
“It gives the space more light by reflecting the ceiling, which is a massive and often unconsidered landscape in a basement. Ceiling is what you experience most in a basement, in fact.”
As such, there was a conscious decision not to have spotlights. “It would have broken the clean lines of the space,” he says.
The function of the kitchen is all on the left and in the island. Closest is a fridge-freezer, then pantry storage, pan drawers and cutlery storage beneath a zoneless induction hob, then double ovens. At the far end, there’s tall storage for crockery and other dining items. The island houses a dishwasher and bins.
All kitchen fittings, including an KM7678FL induction hob, Miele.
A wall of oak battening runs up the right-hand side of the kitchen. Behind here there’s a cloakroom, a media cupboard and storage. “[The space] is working really, really hard,” John says. Curved detailing helps the flow.
There had previously been a utility room in this run, too, but John moved this up to the half landing above and bumped the loo along, possible because of the staircase changes.
There had previously been a utility room in this run, too, but John moved this up to the half landing above and bumped the loo along, possible because of the staircase changes.
The raised ground floor area, seen here pre-renovation, also felt narrow and lacking in light, despite the glazing.
The new extension has now linked this part of the house to the kitchen and dining area and boosted garden views.
One of the changes was to remove the visual barrier of this built-in cabinet at the far end and replace it with a frameless glass balustrade.
The new extension has now linked this part of the house to the kitchen and dining area and boosted garden views.
One of the changes was to remove the visual barrier of this built-in cabinet at the far end and replace it with a frameless glass balustrade.
Also, a previously separate gallery area that was just outside the room at the far end has become a double height landing (not shown but easier to understand in the photo below). Light from it floods the staircase, which also boosts the sense of space thanks to its transparent balustrade.
The heated stone flooring is another subtle connection to the lower ground floor. “You can look out directly onto the terrace and see the same stone, so it almost brings that terrace inside.”
The heated stone flooring is another subtle connection to the lower ground floor. “You can look out directly onto the terrace and see the same stone, so it almost brings that terrace inside.”
John has also changed the vista by reducing frames in the glazing and by changing the sloping glass roof for a right-angled one in the new extension.
The console is a nice slimline piece of furniture for the narrow room; it contains cocktail paraphernalia.
The ceiling is low and, again, John avoided spotlights, opting instead for integrated lighting in the timber-panelled wall. There’s a concealed track for a sheer curtain, should there be a desire for privacy in the future.
There’s more seating in a new library at the other end of the ground floor room.
What did the homeowner make of his newly reconfigured house? “He loves it,” John says. “He had a big party when it was completed and told me that everyone loved the social aspect of it, because it’s connected across floors. He said people were blown away.”
Tell us…
What do you think is the cleverest part of this tweaked extension? Let us know in the Comments.
What did the homeowner make of his newly reconfigured house? “He loves it,” John says. “He had a big party when it was completed and told me that everyone loved the social aspect of it, because it’s connected across floors. He said people were blown away.”
Tell us…
What do you think is the cleverest part of this tweaked extension? Let us know in the Comments.
Who lives here? A sociable businessman with grown-up children who come to visit
Location Chelsea, London
Property A Georgian townhouse in a conservation area with three bedrooms and three bathrooms
Room dimensions Ground floor, 10m x 4.5m; upper ground floor, 7.4m x 4.65m
Designer John Crowley of Anthro Architecture
Project year 2023
Photos by Ingrid Rasmussen
As this historic building is in a conservation area, John knew it would be difficult or impossible to alter its footprint, so his thoughts turned instead to how he could transform the internal space. “We knew we’d be limited in what we could add, and we didn’t want to lose garden space, so we focused on what was there,” he says.
His game-changing solution? “On the first visit to the site, it was about the stairs,” he recalls. “I thought, if we could change the stairs, we could create a double-height space and connect to the garden.”
The design of the stairs was such that it made the rear space feel narrower. “One sofa was all you could squeeze in [at the garden end],” he says. “And on the upper floor, there were two small rooms. Our brief was to open up the floor plan and connect the house with the garden across the rear.”
John redesigned and rebuilt the existing extension, and moved the staircase, pulling off a clever transformation.
Large Glifo wall light, Penta Light.