Secure Windows Against Burglars | Ventilate Safely

Two houses broken into on the same day, both through open windows, both between 10am and 4pm, while the owners were out going about a normal Tuesday. Cash and jewellery taken. No forced entry, no smashed glass, no drama at all from the burglar's point of view. Just an open window and a few seconds.

That's what happened in Eastergate and Westergate on 7 July 2026, according to the appeal Chichester Police put out two days later. Sussex Express picked it up the same morning. It's the kind of story that gets shared around local Facebook groups for a day or two and then gets forgotten when something else comes along.

I'd rather you didn't forget it.

Because here's the thing: Eastergate and Westergate aren't some other county. They're twenty-odd miles from Crawley. The same warm weather that opened those windows opened windows in Three Bridges, Tilgate, Bewbush, Broadfield and every other neighbourhood across the RH10 and RH11 postcodes. The conditions are identical. A hot July afternoon, nobody home, a ground-floor window left on the latch for air. Any opportunist driving slowly down a quiet road looking for exactly that gap is going to find it in West Sussex wherever they happen to be.

This isn't meant to alarm you. It's meant to be useful.

What the police warning actually tells us

Chichester Police's appeal was short and to the point: lock your windows when you go out, even briefly, even in the heat. That advice is correct but it's also incomplete, because it assumes the choice is binary. Either you sweat indoors, or you open your windows and take the risk.

You don't have to choose between those two options.

The real problem these burglaries expose isn't that people left windows open. It's that a fully open, unrestrained window is also a fully usable entry point. If you could leave that window open twelve centimetres for airflow and physically prevent anyone from opening it further, you'd have airflow and security at the same time. That's not a complicated idea. The products to make it happen cost less than a round of drinks.

But almost nobody fits them, because almost nobody thinks about windows until there's a reason to.

Now there's a reason.

Why windows get ignored while doors get all the attention

I fit anti-snap cylinders and British Standard deadbolts every week. Homeowners in Crawley, Horley, Haywards Heath, Burgess Hill, they've heard about door security. Insurance companies mention it. Estate agents mention it. There's a whole conversation around TS007 3-star cylinders and BS3621 mortice locks and it's a good conversation to have.

Windows barely get a mention.

And yet a double-glazed unit with a standard cockspur handle and no secondary lock is often far easier to defeat than a well-fitted uPVC door with a decent multipoint lock. The glass is a barrier, but it doesn't have to be broken. Ground-floor windows can be pushed fully open from outside in seconds if there's nothing stopping them. First-floor windows aren't as safe as people assume either, particularly at the front of a property where a wheelie bin or a low flat-roof extension gives someone a step up without much effort.

The burglars in the Eastergate and Westergate jobs didn't need to defeat anything. The window was already open. They just climbed through.

What actually works: the practical options

Let me run through what I'd recommend to anyone in a West Sussex property right now. Some of this you can fit yourself in ten minutes. Some of it is better done properly by a locksmith. None of it is expensive.

Sash jammers

These are the simplest, cheapest option and they work on casement windows as well as traditional sashes despite the name. A sash jammer bolts or screws onto the window frame and drops a metal locking bar across the opening gap. You can set it so the window stays open a fixed amount, typically around 100mm, enough for ventilation, and can't be pushed further from outside.

They cost around £5 to £8 each from any decent hardware supplier. Fit one to each accessible window and you've spent less than £50 on a meaningful improvement. They're not the most elegant solution but they work, they pass insurance inspection, and a child can operate them from the inside.

Key-operated window locks with a BS kitemark

For windows that you'd normally close but want secured against being forced open, a BS kite-marked window lock is the right choice. These screw into the frame and require a key to operate. They're recognised by home insurers and many policies require them on ground-floor and accessible first-floor windows, so if you're not fitting them, you may already be in breach of your policy conditions.

Check your policy documents. Look for the section on window locks. Many policies say ground-floor windows must have key-operated locks or locks with a BS kitemark. It's not often enforced until there's a claim. Then it matters a lot.

Brands like ERA, Yale and Avocet make decent window locks at reasonable prices. Expect to pay £10 to £20 per lock fitted. If you've got a letting property in Ifield or Pound Hill, this is something you should be doing routinely between tenancies, not just when something goes wrong.

Window restrictors

A restrictor is different from a jammer. It's usually a cable or hinged arm that lets you hold the window at a set opening angle while the restrictor itself is locked in place. Restrictors are particularly common in flats and in rooms where children are present, because they're also a safety device. But they do exactly the same security job.

A locksmith-fitted restrictor with a locking mechanism will run you around £25 to £50 per window for parts and labour, depending on the window type. That's a morning's job across a typical three-bedroom semi.

Don't forget the handles

Many uPVC windows come with standard cockspur handles that offer almost no resistance to being forced. A Sold Secure-rated espagnolette handle or a lockable handle replacement is a cheap upgrade, often under £15 in parts, and fits in minutes. If your handles are the original builder-grade fittings on a property more than ten years old, they're worth replacing regardless of anything else.

The daytime burglary pattern and what it means for Crawley

Both the July burglaries happened in daylight hours on a weekday. That's not unusual. Most opportunistic residential burglaries in the south-east happen between roughly 10am and 3pm, when houses are most likely to be empty. People are at work, at school runs, at supermarkets. The street looks quiet and normal.

An opportunist doesn't want confrontation. They want an empty house and an easy entry point. An open window on a warm summer's day is both of those things at once.

The Crawley and Gatwick corridor is high-footfall. Lots of commuters, lots of shift workers, lots of people out of the house on predictable schedules. Maidenbower, Gossops Green, Northgate, these are ordinary residential streets with ordinary routines that aren't hard to read from outside. I'm not saying that to frighten anyone. I'm saying it because it's the reason basic passive measures like window restrictors matter more than people think.

You don't need to turn your house into a fortress. You just need to be a slightly harder target than the next one.

My honest opinion on the police advice

Telling people to keep windows shut in a heatwave is well-meaning but it sets up a choice nobody wants to make, especially in an older property without air conditioning. People will leave windows open. They always do. The weather this July has been stubborn and the houses in older Crawley estates don't breathe well.

Better advice would be: fit restrictors and jammers, leave windows open safely, and make sure you're not breaching your insurance conditions at the same time. That's achievable. Asking people to suffer in a hot house is not a security strategy.

So my position, for whatever it's worth, is this: the police did the right thing issuing that warning. The two daytime jobs in Eastergate and Westergate are a useful and timely prompt. But the response shouldn't be 'shut everything'. It should be 'fit secondary security and ventilate safely'. Those are not the same thing.

If you're a landlord, this is also a liability question. If a tenant reports that a window can't be adequately secured and a burglary then occurs through that window, the conversation about your duty of care gets uncomfortable quickly. Fit the locks. It's cheap and it's the right thing.

What to do this week

If you're in Crawley or anywhere across the RH10 to RH12 area, here's a sensible sequence:

• Walk around your ground floor and any accessible first-floor windows. Count how many have nothing beyond a standard handle to stop them being opened fully from outside.
• Check your home insurance policy for window lock requirements. If it says BS kite-marked locks are needed and you don't have them, you have a gap.
• Buy sash jammers for any window you want to leave partly open for airflow. Fit them today.
• Get a locksmith to supply and fit proper key-operated locks on the rest, particularly any window that's regularly unattended and out of sight from the street.

That's it. Not complicated. Not expensive. A standard three-bedroom semi with six or seven accessible windows would cost somewhere between £80 and £180 all in, parts and labour included, depending on what's already there.

For what it might save you, in stress, in lost items, in an insurance claim that gets knocked back, that's not a difficult decision.

If you want a hand with it, Rapid Response Locksmiths covers Crawley and the RH postcodes, typically arriving within thirty minutes on call-outs. Window lock supply and fit is a same-day job in most cases. Pricing is given honestly on the call before anyone turns up. No obligation to book, no pressure if you'd rather DIY it, but if you want it sorted properly and quickly, we're around.