How a building is actually assembled — each process is broken into phases, layers and the materials it involves, every one linked to its technical sheet.
A well-installed ETICS is not recognised on handover day: it is recognised ten winters later, when the facade is still flat, dry and free of anchor "ghosts". The difference is not made by the materials — it is made by the hand that installs them, and by the time that hand is given.
Open the process →A ventilated facade is a silent machine: behind the slabs, an air channel works every summer afternoon carrying heat away. But the machine only works if the substructure is true and the air can enter low and leave high — the rest is scenery.
Open the process →A CLT structure is not built: it is assembled. The real work already happened at the factory, at cutting; on site remain the precision of the first wall, the right screws in the right places, and one true rule — timber must never touch concrete nor stay wet while standing still.
Open the process →A ventilated roof doesn't just keep water out: it keeps summer heat out and winter moisture away, letting a thread of air run beneath the tiles — from eave to ridge, all year round.
Open the process →In the inverted roof the insulation sits above the waterproofing, not below: the membrane stops baking in the sun and freezing at night, and lasts twice as long.
Open the process →A wall that carries, insulates and breathes with a single material: the porous clay block is the single-leaf answer to nZEB — but it forgives very little at the joints.
Open the process →A timber frame wall weighs a fifth of a masonry wall and insulates twice as well: yet all its value lies in two thin layers nobody sees — the airtight layer and the vapour check.
Open the process →A renovation plaster does not stop rising damp: it gives the moisture somewhere to evaporate and the salts somewhere to crystallise, away from the surface you look at.
Open the process →Underfloor heating is not judged the day it warms up: it is judged the day the screed cracks — and by then it is already under two centimetres of tile.
Open the process →A curtain wall does not sit on the building: it hangs from it. Everything it does rests on two invisible ideas — one load-bearing bracket per mullion, and a joint that drains instead of sealing.
Open the process →In steel the structure is not built, it is assembled. The real work happened in the shop, and three things left on site decide the outcome — the level of the holding-down bolts, the temporary bracing and the bolt torque.
Open the process →Below the water table there is no such thing as maintenance: whatever is laid before the pour stays there forever. That is why bentonite is not a membrane like the others — it is not glued down, it is allowed to swell, and it works only if something stops it swelling freely.
Open the process →In fair-faced concrete the finish is not applied afterwards: it coincides with the first three millimetres of the pour. Everything the site does — the formwork, the release agent, the compaction — stays written on the wall forever.
Open the process →A translucent wall is not designed to see out of: it is designed to bring light in without glare and without showing anything. It has two precise enemies — thermal movement, which here is enormous, and condensation, which forms inside the panes and does not leave on its own.
Open the process →A bio-based material does not fear moisture: it fears moisture that cannot leave. The whole technique of these walls rests on one rule — keep the base high, the roof overhanging, and every layer more vapour-open as you move outwards.
Open the process →Aerated concrete forgives almost everything except two things: a first course out of level and water. The first cannot be recovered, because a two-millimetre joint leaves no room for correction; the second stalls the site for months.
Open the process →Timber outdoors does not rot from rain: it rots from water that cannot leave. The whole technique of decking lies in a few millimetres of air under the board and a couple of degrees of fall.
Open the process →The biggest gain in this job does not come from adding: it comes from taking away. The rubble fill sitting on the floor often weighs more than everything you want to put on it, and removing it is worth more than half the strengthening.
Open the process →A green roof is not a garden put up high: it is a piece of drainage engineering that happens to be green. Its main job — holding water back and releasing it slowly — takes place under the substrate, in layers nobody will ever see again.
Open the process →Roofs almost never leak in the middle of a slope: they leak at the junctions. Flashings are five per cent of a roof's area and ninety per cent of its leaks, and everything hinges on two things — letting the metal move, and never letting it touch the wrong metal.
Open the process →Weathering steel protects itself, but only if it is allowed to dry: the patina does not form in damp, it forms through wet-and-dry cycles. And for the first three years it runs — whatever sits below the facade has to be designed beforehand, not cleaned afterwards.
Open the process →A sandwich panel arrives finished: structure, insulation and finish in one piece. Which means everything still left to get wrong is in the joints, the fixings, and one decision made upstream — what the core is made of.
Open the process →The moment a pane has a cable, the facade stops being an envelope and becomes a building service. Everything changes: who installs it, who commissions it, who repairs it — and above all, a pane can no longer be replaced without an electrician.
Open the process →Frost does not break stone from above: it lifts it from below. Water that enters the joint and finds no way out stops under the slab, freezes, expands and pushes everything off — which is why external paving is a drainage problem before it is a laying problem.
Open the process →An ETFE cushion does not hold up because it is stretched: it holds up because it is inflated. Its stiffness is air at slight overpressure, which means the roof has a mechanical plant that never switches off — the first roof with an electricity bill.
Open the process →A perforated panel on its own absorbs almost nothing: what absorbs is the system — holes, air cavity and wool behind. Take the wool away and you are left with a pattern; clog the holes with paint and the pattern is all that is left.
Open the process →A high-class window is worth nothing if the joint around it is not designed. The declared performance belongs to the frame tested in a laboratory, not to the hole in the wall: it is the joint that decides how much of it survives on site.
Open the process →A seamless floor does not hide the substrate's faults: it amplifies them. The finish is a few millimetres thick and has no joints in which to release stress, so everything underneath — moisture, cracks, joints — comes back to the surface.
Open the process →The first act of restoration is not applying: it is recognising. Historic plaster must be read before it is touched, because it is almost never a single plaster — it is layers from different periods, and what looks like decay may be the original finish.
Open the process →A drywall partition does not perform because it is thick: it performs because it is a system. Changing one screw, skipping a strip or leaving a hole for a cable is enough to void both the acoustic and the fire performance, which are declared for the assembly and not for the board.
Open the process →It is the intervention with the best cost-to-result ratio in the whole retrofit, and also the one most often botched: because it cannot be seen. Once the wall is closed, nobody can say whether the cavity is full or half empty.
Open the process →Glulam is engineered in the shop and assembled on site: once it arrives, it can no longer be modified. Every hole, notch and plate must exist on the drawing months earlier, because a beam cut on site has lost its strength.
Open the process →Infill masonry carries no vertical load, and for that reason it gets treated as filler. It is the misunderstanding that costs most lives in earthquakes: a stiff masonry panel wedged into a flexible frame is not neutral, it participates — and if it participates badly, it goes out of plane and falls.
Open the process →Spalling cover is not the disease: it is the symptom. Beneath it is reinforcement that is rusting, and rust occupies far more space than the steel it comes from — that expansion is what blows the concrete off.
Open the process →Here glass does not close an opening: it restrains a person or carries them. The design question is not whether it resists, but what happens when it breaks — because glass does break, and it is the post-breakage behaviour that is specified.
Open the process →A standing seam roof is not watertight because it is sealed: it is watertight because it is folded. The joint between two bays is an upstand folded over twice, standing well above the plane the water runs on, and not a single fastener pierces the covering. That shifts the design question: not "how do we close it", but "how do we let a metal that grows several millimetres per metre in summer move freely".
Open the process →A flat roof is not flat, and must not be: it is a surface shaped so that water finds its own way to the outlets. The membrane is only the last link. The two questions that decide the outcome are asked long before: where does the water go, and what holds the covering down when the wind stops pushing and starts pulling.
Open the process →Concrete is not a material that arrives on site: it is a material born on site, and born only once. Everything decided before the pour is design; everything discovered after it is demolition. Which is why the most important phase of this process is not the pour, but the two hours before it.
Open the process →On site, concrete is born once, under whatever weather the day brings, and cannot be inspected until it is too late. In the factory it is born a thousand times identical, under cover, and every unit can be looked at before it is erected. The price of that gain is exact: everything that is born continuous in cast in-situ work becomes, here, a joint.
Open the process →Shading is not there to cast shade: it is there to cast shade in summer and get out of the way in winter. The whole design lies in that difference, and the difference is not settled by taste: it is settled by solar geometry, which behaves so differently to the south and to the west that it demands two different devices.
Open the process →These are the oldest roof coverings there are, and they work on a principle no modern material has improved on: no element is waterproof, no joint is sealed, and yet the water does not get in. It gets in and finds its way out. Watertightness comes not from closure but from overlap, which is why a shingle or stone slab roof is not designed in millimetres of membrane: it is designed in degrees of pitch and centimetres of cover.
Open the process →Render is the layer everyone treats as a finish and which is in fact a structure: it sits between masonry that moves and a finish that refuses to move, and its job is to make the two live together for decades. Almost all of its defects arise not from the mix but from a decision made earlier: putting a stiffer layer on top of a weaker one.
Open the process →In a building, water is outside and must be kept out. In a basin, water is inside and must be kept in, and that reverses every rule: the pressure comes from the opposite side, the liner works in tension rather than in bearing, and the weak point is never the bottom. It is the edge, where the lining has to finish somewhere.
Open the process →Insulating from the inside is nearly always the second choice, done when the first is blocked: a listed facade, a building line that allows no projection, a condominium that will not vote it through. It must be approached knowing that it is not external insulation applied on the wrong side: it is an intervention that changes the wall's thermal regime, and that can damage it if treated as a matter of centimetres.
Open the process →Paint protects steel by hiding it from the environment: where the film stops, the protection stops. Zinc works in a completely different way, and grasping this changes every subsequent decision: it is consumed instead of the iron, so it goes on protecting it even where the steel has been left bare.
Open the process →Radiation and noise are utterly different physical phenomena, yet they are stopped by the same material and for the same reason: mass. Lead is used where a great deal must be stopped within little thickness, and in both cases one rule admits no exceptions: a shield is worth what its weakest point is worth, and that is never the sheet. It is the joint, the screw, the socket box.
Open the process →Intuition says the worst-suffering part of a jetty is the submerged one. The opposite is true: underwater there is little oxygen and decay slows down. What is consumed is the band that alternates wet and dry, where the sea arrives, evaporates and leaves the salt behind. Designing for the sea means recognising that the same structure lives three different lives at three different levels.
Open the process →Weathering steel is not a steel that does not rust: it is a steel that rusts once and then stops. But that patina does not form by itself in any condition: it needs to get wet and to dry, cyclically. Where water stagnates it never stabilises, and where water never reaches it never forms at all.
Open the process →A raised floor is not bought for the floor: it is bought for the void beneath it. The entire value of the work lies in being able to open it in ten years and find something orderly inside, and anything that compromises that — a panel that will not come out, a cable laid across the grid, a fitting screwed to the surface — destroys the reason it was chosen.
Open the process →A SIP panel does not have a structure and an insulant: it is both at once, because the insulating core is what makes the two facings work together. That is elegant and efficient, and it carries one consequence that governs the whole site: you cannot cut it. Everything not decided before production becomes, later, a structural alteration.
Open the process →A frameless glass wall looks like the simplest of constructions: two profiles and a panel. In fact it is the one interior system where the site has no room to adapt anything. Toughened glass arrives finished and any attempt to correct it destroys it: the whole job is decided in the survey and in the preparation of the bedding line.
Open the process →A printer does not build a wall: it lays down a sequence of beads that have to stay in equilibrium until the next one arrives. The real design document is not the elevation but the nozzle path, and the parameter that decides success is not the 28-day strength: it is the time that elapses between one layer and the next.
Open the process →In a sewer the concrete is not consumed where the sewage flows: it is consumed above, in the crown, where the liquid never reaches. What eats it is a gas — hydrogen sulphide — which certain bacteria turn into sulphuric acid on exactly the damp surface that no flow ever washes. Designing a durable sewer therefore means dealing with the hydraulics first and with the material only afterwards.
Open the process →Geofoam is not insulation that ended up underground: it is a construction material chosen for what it lacks, namely weight. It is used when the ground cannot carry the embankment the design calls for, and the answer is not to strengthen the ground but to remove load. From this follows a complete inversion of the problems: the fear is no longer that the works will sink, but that they will float.
Open the process →Sodium bentonite does not waterproof while dry: it waterproofs by swelling. It is the only sealing material that needs the very water it has to stop, and the only one that closes a small puncture by itself. In exchange it demands one precise condition: to be confined. If the swelling finds a void to expand into, it goes there instead of tightening, and the system fails.
Open the process →In an outdoor timber structure you do not design the timber: you design the water. Every detail that holds it becomes a point of decay, and durability is almost entirely a matter of geometry — covered end grain, raised bearings, surfaces that shed — long before it is a matter of species and treatment. The second check is not weight: it is wind, because a covered pergola is a sail.
Open the process →Temporary works are the one construction on site that nobody draws and everybody walks through. They exist to protect people and finished work, and they are almost always assembled from offcuts by whichever crew has the least time. Treating them as a construction — with a drawing, a check and someone responsible — costs little and changes the number of accidents.
Open the process →A road safety barrier is not there to resist the impact: it is there to deform to a script. It is the one element of an infrastructure designed to give way predictably, and its performance comes not from a calculation but from a full-scale test. Hence the rule that governs the whole site: any variation — a different bolt, a missing spacer, a shorter embedment — produces a barrier that has never been tested.
Open the process →A base-isolated building is not stronger: it is slower. The bearings lengthen the natural period of the structure until the earthquake no longer finds it in resonance, and the price of that choice is that the building has to be able to slide. Everything else on site follows from this: anything crossing the isolation plane — a pipe, a cable, a stair, a pavement — has to be designed to move, otherwise it becomes a rigid bridge that cancels the system.
Open the process →Terrazzo is not a floor that gets laid: it is a floor cast in place and then uncovered. The surface that will be seen does not yet exist when the mix is poured — it sits inside the mix, a couple of millimetres lower — and grinding is not a finish but the moment the design becomes visible. That is why the only drawing that counts is the one of the brass strips: they are the one thing decided beforehand that cannot be corrected afterwards.
Open the process →