Why are Amsterdam's houses crooked?

Why do Amsterdam's houses lean forward?

Stand on a bridge and look along a row of canal houses. Plenty of them aren't upright: they tip towards the street, as if leaning out over the water. And often it's no accident, but a way of building that has its own name in Dutch: op vlucht. As early as 1532, an Amsterdam bylaw set how far wooden façades could lean forward. According to the architectural historian Ruud Meischke, the rule seems to have been more about keeping the street looking orderly than about checking how houses were built. And the habit carried on along the 17th-century canal ring, where there had never been overhanging wooden houses at all.

So what was it for? This is where we're into hypotheses. The most typically Amsterdam explanation has to do with the hook you'll see sticking out near the top of many façades: the lean would have made the pulley's job easier when hauling goods up. Meischke doesn't buy it, because houses were being built leaning forward before anyone hoisted goods up the front. Another points to a visual effect, meant to be seen from the street. The one he finds most reasonable looks back to the days when wood and brick were mixed in the same façade: tilting it would have kept the rain off the wooden window frames and all their leaded glass. Even he presents it as a supposition. So if anyone gives you one single, certain answer, take it with a pinch of salt.

Is Amsterdam sinking?

The other half of the answer is under your feet. According to the city council itself, the first Amsterdammers lived on the banks of the Amstel around 1200, in houses that sank into the peat, and the ground had to be raised every so often. Then came wooden piles driven into the mud. At first they went in about seven metres, but the firm layer lies deeper: by the early 17th century it was clear they had to go twice as deep to reach solid sand. For centuries, the city's buildings have rested on piles.

Driving them in was back-breaking work. A wooden frame held a block of about 400 kilos, which some thirty men hauled up on ropes and let drop onto the pile, over and over again. It was dangerous, and there were casualties and mistakes.

Skimp on that hidden part and the ground made you pay. In the 19th century, the De Pijp district went up in a hurry, put up speculatively by contractors living on loans. Every month on site meant more interest, so they cut corners on the piles, which were too short, and on the beams, which were too thin. On 21 September 1876, two houses under construction on Ferdinand Bolstraat collapsed. That comes from a local history source; we haven't been able to check it against the newspapers of the time.

So there are two kinds of crooked house. Those that lean towards the canal, many of them on purpose. And those that have given way on ground that has never been entirely trustworthy. What isn't true is that they're all crooked because they're sinking. Which is which, house by house, only someone who studies each one closely can tell you.

Why are Amsterdam's houses so narrow?

Many canal houses are only three or four windows wide, and inside they're as long as a corridor. Dutch has a nickname for that: pijpenla, the long, narrow box people once kept their tobacco pipes in.

You've probably heard the explanation already: tax was charged on the width of the frontage. It's the most popular version. The trouble is that no document from those years has ever turned up to support it. It hasn't been proved or disproved. There's simply no evidence.

What is on record is how the land was sold. In the early 17th century, Amsterdam launched its great expansion: a belt of three new canals curving round the old centre. UNESCO calls it the largest and most homogeneous urban extension of its day. The council parcelled up the land and put it on sale, with strings attached. Each plot was 180 feet deep, about fifty metres, but only the first hundred feet could be built on. The rest had to be left unbuilt.

Do the maths. If you can't build backwards, more house means more frontage, and more frontage means buying more plot. The rules even covered the front steps, which could jut out no more than four feet onto the main canals, and no more than two elsewhere.

The beginnings literally stank. In May 1618 the city council received a complaint from the new residents about the smell. Many plots were still empty and waterlogged, and their owners were made to fill them in without delay. And a scholar writing in the early 20th century pointed out the plan's great oversight: those plots were absurdly deep for modest houses, and the authorities knew homes would be needed for working people but didn't provide for them. In his view, without the Jordaan, the working-class district that grew up beyond the outermost canal, the plan would have failed.

What are the hooks on Amsterdam houses for?

Look up to the top of the façade. On many houses a beam with a hook sticks out: the hijsbalk, or hoist beam. Merchants' houses doubled as warehouses, and goods were hauled up to the lofts with a pulley. Often the larger central window gives away where that storage loft used to be. The beam hasn't retired, either: these days it's used to lift furniture when people move house.

Fact or legend?

• Fact: plots on the canal ring were 180 feet deep and only 100 could be built on; there were rules even for the front steps; in 1618 people complained about the stench of flooded plots. The hooks were for hauling goods. The old city rests on wooden piles driven into peat. Many façades were built leaning forward on purpose (op vlucht), and a bylaw of 1532 already limited how far wooden ones could lean.
• Single source: the two houses that collapsed during construction in De Pijp in 1876.
• Hypothesis: why they leaned. Helping the pulley (unlikely: the lean is older than hoisting up the front), a visual effect, or protecting façades that mixed wood and brick.
• No evidence: the tax on the width of the frontage.
• False as a general rule: that every house is crooked because it's sinking.

Where to hear it

The story of the plots, the tax nobody has found and the hooks is told at the stop "Plots a Hundred and Eighty Feet Deep", the second on the route "Western Canals: Anne Frank and the Westerkerk". Further on, at "Names Can Mislead", you reach the Jordaan, the district the plan forgot. The houses that fell down are on the route "De Pijp: A Neighbourhood Built in a Hurry", at the stop "The Sinking Houses". The lean doesn't have a stop of its own: as you walk along the canals, keep an eye on the façades.

If you're planning your trip, our Amsterdam guide has the practical side.

Further reading

• W. B. Peteri, "Een en ander uit de bouwgeschiedenis van Amsterdam", De Tijdspiegel 72 (1915), pp. 331–343, on DBNL (in Dutch): https://dbnl.org/tekst/_tij008191501_01/_tij008191501_01_0077.php
• UNESCO, "Seventeenth-Century Canal Ring Area of Amsterdam inside the Singelgracht", no. 1349: https://whc.unesco.org/en/list/1349/
• Gemeente Amsterdam, "Amsterdam, stad op palen" (2021, in Dutch): https://www.amsterdam.nl/nieuws/achtergrond/stad-palen/
• Gemeente Amsterdam, Monumenten Inventarisatie Project, MIP-Amsterdam, Wijk 2 (in Dutch): https://020apps.nl/mip/beschrijvingen/Wijk%202%20Amsterdam.pdf
• Dwars door Amsterdam-Oost, "Ingestort huis… Pieter Nieuwlandstraat 48" (2020, in Dutch): https://dwars-door-amsterdam-oost.nl/ingestort-huis-pieter-nieuwlandstraat-48/
• Ruud Meischke, "Voorpui-overstekken en gevels op vlucht", Jaarboek Monumentenzorg 1996. Monumenten en bouwhistorie, pp. 47–52, on DBNL (in Dutch): https://www.dbnl.org/tekst/_jaa030199601_01/_jaa030199601_01_0007.php