What makes hinges suitable for exterior use?

[JT101]

Or more to the point, I am looking for some suitable 100mm butt hinges that will be severely exposed.

I have roof windows on my greenhouse which I need to open. This is out on an allotment so it is very exposed.

I have used cheap hinges in the past, but they have seized up being constantly exposed to dirt and rain. They need to be free moving under such conditions because they have auto vents which cannot open the window when the hinge is seized.

Can anyone recommend some hinges and materials please, and explain why they will work.

I originally thought stainless steel with ball bearings would work, but they don't seeem to be rated for exterior use

Thanks

 

[JohnD]

the balls help a heavy door to swing smoothly, but may not be corrosion resistant. I like stainless hinges with a self-lubricated bronze bush (these are commonly used on lift-off hinges, which don't have ball-bearings). You can get a plain stainless hinge which is cheaper. The bronze is also non-corroding (though it might go green) and is used on ships propellors.

The heavy-duty hinges used on fire doors, lift-off, with bronze-bearing, are the more expensive.

For appearance, you can get stainless with PVD brass plating. I am amazed that the ones I used on my shed door have not tarnished after about ten years in a coastal location. I don't know why. They are more expensive than plain stainless and can be harder to find.

The bronze bushes are to take a vertical load, and this type often has a short hinge-pin with a conical (pointed) end so it's easy to lift the door on. All the stress on the hinge-pin comes where the two leaves join, there is no stress beyond that, so most of the length of a hinge pin is wasted.

 

[JohnD]

For your purposes, I'd be happy with the lift-off style because it only has one moving joint. Ordinary hinges have several knuckles where dirt and rain can get in.

If your windows are vertical, like a door, this is a very good hinge. I have never used them on a horizontal/transom window. You might like to use a left-hand and a right-hand in this case to prevent any sideways movement.

PVD, both hands available (I have excess stock of these if you want to save a bit)
https://www.ironmongerydirect.co.uk...ge-102x76x2mm-left-hand-pvd-brass-pair-302905

stainless (the satin stainless is easier to paint, though this is not really necessary)
https://www.ironmongerydirect.co.uk...eft-hand-polished-stainless-steel-pair-184520

continental style (I don't like the appearance, but this is a thicker, stronger hinge with a bigger pin)
https://www.ironmongerydirect.co.uk...-right-hand-satin-stainless-steel-pair-137713

Check if stainless screws are included in the pack, if not, buy some. Drill pilot holes for the screws as the heads seem to be softer than common steel.

 

[JT101]

Hi JohnD

That makes lots of sense. Thanks for all that. So how many of the brass hinges have you got and whether RH or LH?

Just had another thought. What about solid brass hinges if I can get some?

 

[Notch7]

Some info on these types of hinges.......

The ball bearing type door hinges that stainless steel have a limitation: the ball races arent stainless because its too soft.

You can get shrouded options
https://www.coastal-group.com/Hinges-and-Pivots/Shrouded-Bearing-Hinge-304-Gra

The shrouding also stops the oil leakage that is commonly seen -although that is actually the grease used in assembly, not part of the bearing.
And available in marine grade 316 stainless:
https://www.coastal-group.com/Hinges-and-Pivots/HQ-Butt-Hinge-Square-End

A 100mm hinge seems large for a roof opener?

 

[JohnD]

So how many of the brass hinges have you got and whether RH or LH?

I have an opened box of each, PVD brass on stainless. Maybe a dozen pairs. You can have them at half the ironmongerydirect retail price, plus postage, but tell me how many you want as I have to get them out of storage.

p.s.

Ordinary indoor Brass hinges I think have plain steel pins that will rust. IIRC I used some outdoors and eventually the pins jammed and broke.