Security screen doors that actually work

A security screen door is sold as peace of mind. It is a second door, with its own hinges, lock and corrosion problem, that has to let air through and keep a determined person out. If it only does the airflow, it is a flyscreen.

I come at this as a locksmith who has spent too many Brisbane summers watching cheap powder-coat bloom and cheap mesh rust at the crimps. The same pattern turns up on a Victorian peninsula and a Darwin verandah, only faster.

What “security” is supposed to mean

In Australian practice a security screen door is not a decorative grille and it is not insect mesh on a light aluminium door. It is a framed panel — stainless mesh, a woven or perforated metal, or a diamond grille — in a door that is hinged or sliding, with locks that resist a shove and a kick.

There are published product and installation standards for security screen doors and window grilles, including the AS 5039 series and AS 5040. They exist because “heavy looking” is not a test. Ask the supplier which standard the door is made and installed to, and keep the paperwork.

A flyscreen is still a good product. It just is not this product. If the brief is insects and a breeze, say so and spend less. If it is a dark side path, spend on the frame and the lock.

316, 304 and the salt you can taste

Stainless mesh is graded. 304 is the common austenitic stainless. 316 has molybdenum and it is the grade you want when salt is in the air or when the door will be splashed from a pool.

The difference shows as tea-staining — that brown bloom on the mesh and at the welds — not as an overnight hole. Once it starts, it looks like rust because that is what it is getting on with. Coastal houses that specify 304 to save a few hundred dollars usually pay it back to a polisher, or to a replacement door.

Match the rest of the assembly:

• Fasteners should be 316 if the mesh is 316. A 304 door held on with cheap zinc screws is a 304 door with rusting corners.
• The frame alloy and the powder-coat matter as much as the mesh. Salt eats edges and mitres.
• Hinges need a pin that will not seize. Stainless or a high-grade coated hinge, not a painted mild-steel butt that was in the bottom of the van.
• The lock furniture should be rated for marine air if the house is. A chrome zamak lever on a 316 door is how the handle pits while the mesh is still honest.

Inland, in a dry suburb, 304 in a decent frame is reasonable. Do not let a coastal salesperson talk you out of 316.

Diamond grille, woven mesh and the view

Woven or knitted stainless mesh is the product most people mean by a security screen. You can see through it. You can talk through it. You get airflow. The security is the tensile strength of the mesh and the way it is clamped in the frame. Cut resistance is the point.

Diamond grille — the expanded or welded lattice you still see on older houses and on some commercial doors — is a different look and a different kick test. It can be very strong. It also turns the verandah into a cage if you let the pattern run too heavy, and it does less for insects unless you add a second mesh.

Perforated sheet sits in between. It is honest about not being invisible.

Choose with the light, not just the showroom sample:

• On a dark south entry, a heavy grille makes the hallway gloomier.
• On a west wall, mesh can heat up. A hand on the door at 4 p.m. will tell you.
• Pets will lean. The mesh has to take a dog that believes in the postie.
• If you want insects and security, you need a mesh small enough for midges or a second insect screen. Security mesh is not always midge mesh.

Hinges, sliders and the lock that does the work

A hinged security door is only as good as three things: the hinge side, the lock side, and the way it is fixed to the jamb.

Hinges should be through-bolted or coach-screwed into something solid, with a non-removable pin so the door cannot be lifted off. Three hinges on a tall door.

Sliding security doors on a wide opening are a track problem as well as a lock problem. They need a lock that hooks into the jamb in more than one place and a track that will not fill with grit.

The lock is where a lot of screens quietly fail. A keyed snib that a shoulder will persuade is not a deadlock. If you care about insurance, specify hardware that meets the relevant parts of AS 4145 and read door locks that meet Australian insurance. Many household policies talk about deadlocks on accessible doors. A screen with a toy cylinder in front of an unlocked entry leaf is theatre.

Practise the daily habit before you order. If the household will not key the screen, a beautiful lock is a paperweight. Sometimes the honest product is a screen that stays locked and an entry leaf that stays open for air.

Cyclone regions, bushfire and the other jobs a screen can have

In wind regions C and D a door that stays in its opening during a cyclone is a structural problem. Some screens are tested as debris screens. Many suburban security doors are not. If the site is in cyclone country, say so on the order and buy the product tested for that use.

Bushfire is a different physics. Embers and radiant heat do not care how hard the mesh is to cut. AS 3959 and the NCC will tell you whether a screen is part of the BAL solution. Metal mesh can help against embers on some openings. Plastics and untreated timber surrounds are not. Take the BAL assessment to the screen maker.

If you need cyclone and security, or BAL and security, you need a system that claims both. Do not invent a dual-rated door in your head.

Airflow, heat and the reason you wanted the door

Australians fit screens so the house can breathe. A security door that turns the entry into a dim, hot airlock has failed even if it would survive an angle grinder.

Mesh open area matters. So does the depth of the porch. A screen on a west-facing unshaded wall will be hot to the touch. In humid weather, a security door that lets you leave the solid leaf open is air-conditioning you do not have to run — the practical win on a Queenslander or a house with a verandah.

If you have a dog that launches, say so. There are heavier weaves, and kick-plates that solve the dog at the cost of a band of airflow.

What it costs, and what a quote should say

Ranges, in Australian dollars, supply and install for a standard hinged opening:

• Light “security-look” doors of no particular rating: $250 to $600. These are the ones I would walk past.
• A rated hinged security door in 304, ordinary size: about $400 to $1,200.
• 316 mesh, custom height, or a heavier frame: about $800 to $2,000.
• Sliding security units on patio widths: often $1,200 to $2,500, more on a stack.
• Cyclone-rated or unusually large systems: treat as a building product, not a screen special. Several thousand is common.

The quote should name mesh grade, frame, lock type and standard, hinges, handing, and how it fixes to timber, brick or steel. It should say who packs out an out-of-square opening.

Lead times are often two to six weeks because the door is made to the hole. Measure twice. A security door that is 8 millimetres short is a security gap.

Installation and the mistakes that keep the locksmith busy

The screen is only as good as the jamb it sits on. Screwing a heavy door into rotten weatherboard is a weekend project that becomes a night-time project. Fix into the stud, a planted jamb, or masonry plugs that actually hold.

Leave clearance for the main door’s hardware. A lever on the entry leaf will fight a screen that was measured as if the leaf were flat.

Keep drainage at the sill. A door that sits in a puddle will stain even in 316.

If the cheapest part of the door is the lock, that is the part that will be tested.

A screen that works is a boring object: correct metal for the air, a lock you will use, hinges that stay, and enough open area that you still want to open the house. Specify those four.