Wimbledon Centre Court Roof: How and When It Closes

On the evening of 29 June 2009, Andy Murray and Stanislas Wawrinka played out a fourth-round match on Centre Court under artificial light, with a fabric roof drawn across the sky above them and a crowd that had expected to be sent home hours earlier. The match finished just before twenty to eleven. It was the first ever completed under the closed roof, and it settled an argument the All England Club had been having with itself for the better part of two decades.

Wimbledon had spent a century organising itself around the possibility of rain. It now had one court where rain no longer mattered.

The problem the Club was actually trying to solve

Rain in south-west London in the first two weeks of July is not an occasional inconvenience. It is a structural feature of the tournament, and for most of the Championships' history the response was the same: covers on, crowd waits, ground staff stand by, and the schedule absorbs the damage as best it can.

The damage was considerable. A washed-out day pushes an entire round back, which compresses the rest of the fortnight, which forces players into matches on consecutive days and occasionally into two matches in one. In the worst years the Championships had to use the middle Sunday — traditionally a rest day — to clear a backlog, and even that was a patch rather than a solution. The wider consequences of a wet fortnight, and the rules governing what happens when play stops, are covered in the guide to Wimbledon's rain delay rules.

Three pressures converged in the 2000s. The first was sporting fairness: a draw distorted by weather is a draw decided partly by the fixture list. The second was the spectator, who by then was paying a great deal for a day that might deliver twenty minutes of tennis. The third, and the one that carried the most weight in the end, was broadcasting. Wimbledon sells its television rights around a schedule, and a tournament that cannot guarantee a single hour of live sport on any given afternoon is selling something with a hole in it.

The Club took a long time to be persuaded. Objections were raised on every ground available: that a roof would compromise the character of an outdoor tournament on grass, that the engineering was not proven on a stadium of Centre Court's age, that indoor tennis is a different sport, and that the money would be better spent elsewhere on the site. Those arguments were not foolish, and versions of them are still made. What settled it was the accumulation of ruined fortnights, and the recognition that a tournament which cannot promise play cannot properly be sold.

The old Centre Court roof — the fixed one that had always covered the stands — came off after the 2006 Championships. Centre Court then played through 2007 and 2008 with construction work going on around it and less cover than it had before, which was a considerable act of faith. The retractable roof was ready for 2009, and it worked from the first week.

• 2009Centre Court roof first used
• 2019No.1 Court roof first used
• 2Courts at Wimbledon with a roof

Dates of first competitive use and the fixed curfew; the Club has not published a court-by-court cost breakdown.

How the folding fabric mechanism works

The roof is not a lid that slides across. It is a concertina, and understanding that explains almost everything about how it behaves.

Running along the east and west sides of Centre Court, above the stands, are banks of steel trusses carrying a translucent, waterproof fabric between them. When the roof is open, the fabric is folded flat and stowed at either side, out of the sightlines, so that an open Centre Court looks essentially the way it always did. When the roof closes, the trusses travel inwards on their tracks and draw the folded fabric out with them, unfolding it as they go, until the two halves meet in the middle above the court and seal.

Two design constraints shaped that solution. Centre Court is a listed part of the site's fabric in spirit if not in law, and the Club was not prepared to alter the look of the bowl or block the view from the upper rows. And the structure had to be light, because Centre Court's existing walls were built in 1922 to hold up a fixed roof over the stands, not a moving one over the court. A folding fabric weighs a fraction of what a rigid panel of the same span would weigh, which is why the engineering went that way rather than towards the sliding-panel roofs used at some other stadiums.

Translucency matters more than it sounds. The fabric admits daylight, so a match played under a closed roof on a grey afternoon is not being played in a black box; the floodlights supplement the light rather than replacing it entirely. That was a deliberate choice to keep covered tennis looking as close to outdoor tennis as possible, and it is the reason television pictures from under the roof look warm rather than clinical.

The mechanism is also slow by design. A roof that moves quickly is a roof with a great deal of kinetic energy in it, and nothing about the operation rewards haste.

Wind is the constraint people do not think about. A large fabric surface moving across an open stadium is a sail, and there are conditions in which the roof cannot safely be operated at all — which is an awkward fact, given that the weather bringing rain frequently brings wind with it. The operating limits are the reason closures are begun early rather than at the last possible moment, and the reason a decision that looks premature from the stands may be the only decision available.

Maintenance is continuous and mostly invisible. The roof is cycled and tested outside the Championships, the fabric and the drive systems are inspected, and the operation is rehearsed by the people who run it, because a mechanism used a handful of times a year is exactly the sort of mechanism that fails when it is finally needed. None of that is glamorous, and all of it is why the roof has been reliable since 2009.

From the first drops to the first serve

The single most common misconception about the roof is that closing it takes ten minutes and play then restarts. The mechanism takes under ten minutes. Play does not restart for roughly half an hour.

1. 1Forecast watchedGround staff and the Referee track the incoming weather well before the first drops arrive.
2. 2Play suspendedThe umpire suspends play on the Referee's authority and the players leave court.
3. 3Covers onThe court is covered as normal while the roof operation begins, because the roof is not instant.
4. 4Roof closesThe trusses travel in and the folded fabric unfolds across the court, taking under ten minutes.
5. 5Air management runsConditioned air is pumped into the enclosed bowl to control humidity and stop condensation forming.
6. 6Court preparedCovers come off, the surface is checked and the lines and net are made ready.
7. 7Warm-upPlayers return for a short warm-up before the match resumes at the point it stopped.

The customary operating sequence as the Club has described it; the timings vary with conditions and are not a published guarantee.

The air management stage is the one that costs the time, and it is not optional. Enclosing fifteen thousand people and a grass court under a fabric roof creates a humid volume of air that will condense on cool surfaces, and condensation on grass makes a court unplayable and dangerous. The system conditions the space until the environment is stable, and only then does the court become usable.

There is a related decision that catches spectators out. Because the sequence takes half an hour, the Referee cannot wait until the rain arrives to start it. A closure begun too late leaves the court wet under a closed roof, which is the worst of all outcomes. So the roof sometimes closes under a dry sky on the strength of a forecast, and occasionally the forecast is wrong, and the Championships spend an hour playing indoors while the sun shines on the queue outside.

Who makes the call, and the rule that keeps it shut

The decision belongs to the Championships Referee. It is not the players' call, not the broadcasters', and not the umpire's beyond the immediate suspension of play. The Referee works with the ground staff, who know the state of the surface, and with the meteorological advice available on site, and takes a view.

One rule governs everything that follows: once the roof has been closed during a match, it stays closed until that match is over.

That rule is the reason the decision is heavier than it looks. Closing the roof mid-match changes the conditions both players are competing in, and reopening it later would change them again, which would be manifestly unfair to whichever player had adapted better. So the Referee is not making a reversible weather call. The Referee is committing the rest of that contest to indoor conditions, sometimes with a set and a half already played outdoors.

The Club's stated position is that Wimbledon is an outdoor tournament played on grass and that the roof exists for necessity rather than convenience. In practice that means the roof is used for rain and for failing light, and not simply because covered tennis would be more comfortable or would suit a broadcast slot better. A dry afternoon on Centre Court is played in the open.

Bad light is the second trigger and it is less discussed. Centre Court has floodlights, and the combination of lights and a closed roof is what makes late finishes possible; without the roof, artificial light alone would leave the court exposed to any shower that arrived. When the light goes at the end of a long day, the roof and the floodlights are used together.

The air system that keeps the grass playable

The roof would be useless without the equipment underneath it, and the air management installation is the least visible and most consequential part of the whole project.

Grass is a living surface with a narrow tolerance. It needs air movement, a controlled humidity and a temperature that does not swing wildly, and none of those things happen naturally inside a sealed bowl holding a full crowd on a summer evening. The system draws in air, conditions it and distributes it through the stadium so that the environment above the court stays within limits the surface can cope with, and it removes the moisture that would otherwise settle on the grass as the temperature drops.

The preparation of the courts is a year-round operation in its own right, and covered play adds a set of demands to it that the ground staff did not previously have to manage — the process is described in full in the guide to how Wimbledon's grass courts are prepared. A court that hosts three matches under a closed roof has had a different week from one that has been open to the wind throughout.

The system also has to cope with a moving target. The volume it is conditioning changes the instant the roof shuts, the heat load changes as the stands fill and empty, and the outside temperature falls through the evening while the inside temperature rises. Running that stably is a continuous balancing act rather than a switch, which is another reason the half-hour before covered play resumes cannot be shortened by simply being brisker about it.

There is a spectator dimension too. Fifteen thousand people under a closed roof on a warm July evening generate a great deal of heat, and part of what the air system is doing is making the stands bearable. That side of the job is rarely mentioned in the engineering write-ups and is extremely obvious if you are sitting in the upper rows in the third hour of a five-setter.

No.1 Court gets its own roof, ten years later

Centre Court's roof was always the first phase of a longer plan, and the second phase arrived for the 2019 Championships when No.1 Court reopened with a retractable roof of its own. The redevelopment also raised the court's capacity and rebuilt its concourses, but the roof was the point.

The reasoning was the same as it had been a decade earlier, only sharper. One covered court guarantees one match at a time. Two guarantee a programme. With both show courts under cover, the Championships can keep a genuine schedule running through a wet afternoon, which is a materially different proposition for a broadcaster and for the spectators sitting in those two stadiums.

	Centre Court	No.1 Court	Everywhere else
Retractable roof	Yes, from 2009	Yes, from 2019	No
Floodlights	Yes	Yes	No
Play continues in rain	Yes, once closed	Yes, once closed	No
Protection when wet	Roof	Roof	Covers and ground staff

What the table makes plain is how uneven the site is. Everything beyond the two show courts remains at the mercy of the weather, which is why a rainy day at Wimbledon can produce the peculiar spectacle of two matches in progress and the rest of the draw sitting in the locker room. The distinction between the show courts and the rest of the site, and what it means for a ticket, is set out in the page on Wimbledon's show courts and outside courts.

The ten-year gap between the two roofs was not indecision. Centre Court had to be proved first, and the No.1 Court project was part of a much larger master plan that also rebuilt the court itself, expanded the concourses and reorganised the northern half of the site. Building a roof onto an existing stadium is far more constrained than designing one in from the start, and the Club had the advantage of a decade of operating experience before it committed to the second.

There is no prospect of covering the whole ground. The cost and the engineering of roofing a court are only justifiable for stadiums that hold thousands of people, and the outside courts are, by design, small.

How a closed court plays differently

Ask ten players and you will get a range of answers, some of them contradictory. This is one of the areas where confident statements should be treated with suspicion.

What is not disputed is that the conditions change. The enclosed air is warmer and more humid than a British evening in the open, there is no wind at all, and the light is even rather than directional. Beyond that, the accounts diverge. Many players describe the ball as feeling heavier and slower through humid air. Many also describe the court itself as playing quicker, because the grass stays drier under cover than it would in the open and the surface does not slow down as evening dew forms. Both things can be true at once, which is probably why the debate never resolves.

The bounce is the most contested point. Some players report a higher, more predictable bounce indoors and prefer it for exactly that reason; others say the ball sits lower and skids more. Court wear, the stage of the fortnight, the individual court and the player's own game all affect this more than the roof does, and separating the roof's contribution from everything else is genuinely difficult.

One effect is consistent and rarely mentioned: sound. A closed roof holds the crowd noise in, and players describe the atmosphere as considerably louder and more intense than the same crowd in an open stadium. For a British player on Centre Court in the second week, that is not a small thing.

Complaints, advantages and the slipperiness argument

The received wisdom is that indoor conditions suit big servers and clean ball-strikers, because the absence of wind removes a variable that helps the scrambler and the retriever. There is a logic to it. Wind is a leveller, and taking it away rewards precision.

The evidence is thinner than the wisdom. Matches under the roof are a small subset of matches played, they cluster in the later rounds where the field is stronger anyway, and no serious analysis has separated the roof's effect from the effect of playing better opponents later in the tournament. It is a plausible claim that has never been properly tested. Treat it as a working theory rather than a finding.

The complaint that has stuck is about footing. In more than one Championships, players have gone down on Centre Court during the opening days with the roof closed, and the incidents have prompted the same question each time: does covered play make the grass slippery? The Club's answer has been consistent and is largely borne out by the agronomy. Grass at the start of a Championships is at its lushest and most closed, with the greatest coverage it will have all fortnight, and a dense sward is more slippery than the worn, bare patches behind the baselines that develop by the second week. The pattern of falls in the first two days is an old feature of grass court tennis and predates the roof by decades.

Where the roof plausibly contributes is at the margin. A closed bowl full of people is humid, and humidity keeps the surface from drying, so a court under a roof in the first week may hold moisture that the same court in open air and a breeze would lose. That is a reasonable mechanism rather than a proven one, and the Club has responded by adjusting its preparation and by monitoring the environment under the roof rather than by conceding the point.

The other regular complaint is about mid-match closure, which is a fairness argument rather than a physical one. A player who has built a lead in windy conditions against an opponent who handles wind badly can watch that advantage disappear in half an hour. Nothing in the rules can prevent it. The alternative — reopening the roof, or refusing to close it during a match — creates worse problems, so the sport lives with an unfairness it cannot design away.

The curfew, and what happens as eleven o'clock approaches

Covered play made late finishes possible, and late finishes ran straight into a planning condition. Play at Wimbledon stops at 11pm.

The curfew is not a Club tradition. It is a condition attached to the planning consent for the Grounds, agreed with the local authority, and it exists to protect a residential area from the disruption of tens of thousands of people leaving a stadium in the middle of the night. It applies regardless of the state of the match, and the full background is set out in the guide to the Wimbledon curfew.

1. 1Late finish forecastThe Referee assesses during the evening whether the match can realistically finish in time.
2. 2Warning pointPlayers and the crowd are made aware that the match may not be completed that night.
3. 311pm reachedPlay is suspended wherever the match has got to, including mid-set.
4. 4Court clearedThe stadium is emptied and the score is held exactly as it stood.
5. 5ResumptionThe match resumes the following day, usually early on the same court, from the identical score.
6. 6Knock-on effectsThe rest of that day's order of play is rebuilt around the resumed match.

The sequence the Championships follow when play approaches 11pm; the curfew itself is a planning condition rather than a tennis rule.

The most famous application came in 2018, when a men's semi-final between Novak Djokovic and Rafael Nadal was still going at eleven o'clock under a closed roof and was suspended for the night, resuming the following day. The curfew took precedence over the semi-final of a Grand Slam, which is a fair indication of how firm it is.

The scheduling implication is that the Referee has to think backwards from 11pm all day. A match starting on Centre Court after about half past eight is unlikely to finish, and the order of play is built with that arithmetic in mind.

Matches that finished under cover

The 2012 gentlemen's singles final is the reference point. Roger Federer and Andy Murray began in the open, rain arrived during the third set, the roof was closed, and the match was completed indoors — the first Wimbledon men's singles final finished under a roof. Whether the change of conditions influenced the outcome was argued about immediately and inconclusively, which is precisely what the closed-roof rule is designed to avoid mid-match and cannot avoid entirely.

The 2009 introduction produced the two firsts already mentioned: the roof's first use during play, and the Murray-Wawrinka match that ran to nearly twenty to eleven that evening. In the years since, covered play has become routine enough that it barely registers as a story unless a final is involved.

A second category of covered match rarely gets written up at all: the ordinary early-round contest that would once have been abandoned for the day and would have distorted a week of scheduling, and which now simply finishes. Those matches are the roof's real justification. A final completed indoors makes the news; two hundred first-round matches that did not have to be replayed on a Wednesday are the reason the investment made sense.

Evening tennis has developed its own character in the process. The crowd that stays until half past ten under a closed roof is self-selected, noisy and considerably more partisan than an afternoon crowd, and players who have experienced both describe the atmosphere in terms usually reserved for indoor arenas rather than for Wimbledon. Whether that suits the tournament's idea of itself is a question the Club has never had to answer out loud, because the roof is used only when the weather demands it.

The counter-example is just as instructive. The 2010 first-round match between John Isner and Nicolas Mahut, which ran to a final set of sixty-eight games across three days, was played on Court 18 — an outside court with no roof and no floodlights, where play stopped each evening for bad light. The longest match in the sport's history happened at a Championships that already had a covered Centre Court, on a court that could not benefit from it. The roof did not change the tournament everywhere. It changed it on two courts.

What the roof changed about running the Championships

The scheduling effects were immediate and the cultural ones took longer.

Immediately, the Referee gained a guaranteed venue. Centre Court could be scheduled with confidence, which meant the marquee matches could be placed there knowing they would be played, and the compression that a wet day forces on the rest of the draw could be partly absorbed. It also meant tennis in the evening, which had never been part of the Wimbledon experience and which now happens most years.

For broadcasters the change was larger still. A guaranteed live sporting event in an evening slot has a completely different value from a probable one, and the roof turned the second week of the Championships into a schedulable property in international markets that had previously had to plan around British weather.

The knock-on effects reached parts of the tournament nobody expected. The old emergency use of the middle Sunday became less necessary once one court was weatherproof, and the tournament's eventual move to fourteen consecutive days of play was a separate decision that the roof made easier — a change traced in the guide to Middle Sunday at Wimbledon. Catering, transport and stewarding all had to be extended into the evening. And the technology on court has continued to develop around covered play, including the officiating systems described in the page on electronic line calling at Wimbledon.

Something was lost as well, and it is worth naming honestly. The rain break was part of the texture of a Wimbledon fortnight: the covers going on to a groan, the crowd singing on the hill, the ground staff sprinting, the whole afternoon suspended and then rescued. On Centre Court that has largely gone. It survives everywhere else on the site, which is one more reason a ground pass and a wet afternoon on an outside court is still a truer version of the Championships than a seat under a closed roof. More on how the fortnight fits together sits in our England guides and the wider tennis section.