Kitchen — first layout

The three appliances, real sizes

Two external walls, not one

• You are right — the sink wall is external too, for its first 112 cm from the corner. After that it becomes the old wall stub with the main room behind. So the north-west corner is a proper external corner and both walls meeting there face the passage.
• That widens the options rather than changing this layout: the hob could duct out either way, and there is a case for a window over the sink as well as the one on the hob wall.

Why the hob stays on the passage wall

• Shortest duct, straight out at low level, and it keeps the sink on the longer run where the dishwasher has to sit beside it.
• It also frees the ceiling — no overhead extractor, nothing hanging in a 2.48 m room, and no cabinet blocking the window.
• The hob can also recirculate, which is the fallback if venting into a side passage turns out to be a problem. Worth checking before you commit — grease and steam into a shared passage is a conversation with neighbours, and possibly with building control.
• The extractor body drops 223 mm below the worktop and must stay accessible from below for the liquid collector. So the cabinet under the hob is mostly given over to the machine — no drawers there.

The fridge drives the south run

• At 905 wide it takes a third of the 283 wall on its own. Putting it at the open east end is what makes it work — both French doors swing clear into the room, and the drawers pull out without fouling anything.
• At 706 deep it projects about 10 cm past a 600 run. That narrows the gangway to 95 cm at that point, against 106 elsewhere. Both are workable; 95 is the number to sanity-check by standing in it.
• It has an ice and water dispenser, so it needs a plumbed supply to a spot that has no water today. That pipe wants running while the floor is open, not after.

Your dishwasher is slimline

• The SPV4EMX25G is 448 wide, not 600 — a 45 cm fully-integrated slimline, 10 place settings, 550 deep. It is a year old and it stays.
• That hands back 15 cm on the sink run. I have put it into the sink unit, which goes from 90 to 105 — enough for a proper large single bowl with drainer, or a bowl and a half.
• It is fully integrated, so it takes a door front matching the rest and disappears into the run.
• Worth knowing: if you ever go to a 600 machine, the 15 cm is recoverable by taking the sink unit back to 90. Nothing here forecloses it.

Worktop audit — you are right

• 310 cm is not a small number, but it is six pieces, and the largest is 128. There is no generous single prep zone, and the best one is across the gangway from the sink.
• The fridge is what causes it. On the 283 wall it takes 95 and the oven housing takes 60 — 155 of tall units, leaving 128. An American fridge is the single most expensive thing in this pocket in terms of worktop.

Three ways to fix it

• Oven under the counter instead of a tall housing. Run C goes from 128 to 188 continuous, total 370. The HMG7764B1B fits either way. Costs you the eye-level oven and the store above it — and bending down to a hot microwave-combi is a real downside worth weighing.
• A peninsula extending the sink run east — drawn dashed on the plan. Run A stops at 219 only because the wall does; east of that is open room. A 120 peninsula adds 120 of continuous worktop, total 430, plus an overhang for stools. It leaves 111 cm to pass between its end and the party wall run, which is comfortable.
• Both gets you to 490, which is a generous kitchen by any measure.

Against what you have now

Uninterrupted runs, which is what matters

• As drawn, the new kitchen is a step backwards on prep. Today’s best run is 190; the new one is 128. The extra tall units — a 95 fridge and a 60 oven housing that the pocket does not currently carry — land squarely on the run that is your prep area today.
• Moving the coffee station out is already counted. Every proposed figure assumes the machine, grinder and Kenwood have gone to the party wall. That is worth about 90 cm and it is the single biggest free win in the room — but do not add it twice.
• Your instinct about run C is fair. A back run flanked by an oven and a services cupboard becomes a landing and dumping surface whatever the drawing says. Counting it as prime prep flatters the scheme.
• Which leaves the peninsula doing the real work. It is the only proposal here that creates a run you would actually choose to cook on — open on both sides, facing the room, directly opposite the sink rather than round a corner.

If prep space is the priority

• Peninsula plus oven under the counter is the honest answer: 188 and 120 as two proper runs, and only then are you clearly ahead of today.
• Or reconsider the fridge. 905 wide is the single most expensive object in this pocket. A 700–750 French door, or a tall larder fridge with the freezer elsewhere, hands 20–35 cm straight back to run C. Worth weighing against 402 litres of fridge.
• Worth saying plainly: the pocket is not the constraint. 703 cm of wall is generous. The constraint is that you are asking it to hold an American fridge, a tall oven housing and a hot water cylinder that it does not hold today.

Going all-electric — the real number

• The hob alone is 7.4 kW connected load. Add the oven, the heat pump, an immersion, washer and dishwasher and you are notionally over 20 kW — more than an 80 A supply.
• The hob has power management and can be set to run on a 16 A, 13 A or 10 A connection. That single feature is usually what makes an all-electric flat work without touching the incoming supply.
• Even so: get the main fuse rating and the consumer unit assessed early. If a DNO upgrade is needed it is measured in months, and that would be the one thing on this project that genuinely cannot be rushed before November.

The cylinder goes where the boiler was

• The boiler corner is the right home for it. The main already arrives there, the stopcock is already there, and the wall is external for the discharge pipe. Moving the cylinder anywhere else means re-routing the incoming main for no gain.
• It is also a blind corner — the one place in a kitchen you cannot use properly anyway. Putting something there that needs annual access rather than daily access is exactly the right trade.

• Under a 900 worktop you have about 860 mm. To get 180 L into that the cylinder needs to be roughly 520 across — fits a 600 unit, but far squatter than the 1200–1800 tall ones most heat pump systems ship with. It is a specific product to source, and the coil surface area needs checking for heat pump flow temperatures.
• If it turns out you need a tall cylinder, this corner cannot take it and the layout changes — so resolve it before any joinery is ordered.

The stopcock costs you the corner

• Corrected twice over: it already is a quarter-turn valve, and labelling an access hatch would not help either. Reaching it means emptying the cabinet and lifting a taped panel — so real access means giving up that cabinet as storage entirely.
• Agreed approach: the corner becomes a services cupboard. Extend the incoming main a short distance so the valve sits hard at the front of the cabinet, with the cylinder behind it, and put a full-width door on the whole thing. One door, nothing stored in front, valve reachable in seconds.
• The pipe extension is the part that makes it work. Without it the cylinder simply sits between you and the valve and you are back where you started.
• What it costs: the corner as storage. Which is the cheapest loss available — a blind corner was never good storage, and a carousel in it would have been worse than the drawers you have elsewhere.
• Also fits in there: expansion vessel, tundish and the discharge run, which all have to live near the cylinder anyway. Worth sizing the cupboard for the whole set, not just the cylinder.

On losing the boiler

• Not just an Australian view — a wall-hung boiler in a small kitchen costs you the best cabinet position in the room and about 0.4 m² of wall. Taking it out is what makes this corner available at all.
• The catch is honest: a heat pump does not give the space back for free. The cylinder is bulkier than a combi and it has to live somewhere. Here it goes into the blind corner, which is the closest thing to free space a kitchen has.

What the layout gives you

Before this goes further

• Window widths and cill heights. Confirmed there are two, both running to the ceiling, meeting at the external corner. Their exact widths decide how much wall cabinet you actually get — currently 107 on run A and 60 on run B. Still the most useful tape measure left.
• Ducting out into the side passage — permitted, and acceptable to the neighbours?
• Main fuse rating and consumer unit — the long-lead item if it needs changing.
• Whether the oven goes Series 8 without the microwave — same 60×60 niche either way, so it does not change this drawing.