How to fit a Suffolk latch

Also known as a thumb latch, the Suffolk Latch is a very simple latch that as well as being used on gates and external doors can also be used on internal cottage style ledged and braced doors. Being a latch only, if used on an external door then some kind of secure lock should also be added for security. Similar to the Suffolk latch is the Norfolk latch, the only difference between the two is that the Suffolk latch has no back plate that the handles are attached to, other than that the fitting of both is the same.

That said, these days the name is practically interchangeable with Suffolk latch being the most commonly used. Both the Suffolk and Norfolk latches were incidentally designed by the same man, one William Twopeny (1797-1873) who produced all manner of designs in metalwork! His book of drawings is online and well worth a look if you’re interested and can be found at https://archive.org/details/englishmetalwork00twopuoft

Depending on the make of latch you’ll be fitting you’ll have between three and five different pieces comprised of the following –

• A – Suffolk latch handle
• B – Thumb latch
• C – Lever bar
• D – Latch bar
• E – Latch bar plate
• F – Keep
• G – Receiver

The Suffolk latch handle sits on the closed side of the door – i.e. as you would open the door you would swing it open away from you. The thumb latch is combined/attached on all Suffolk and Norfolk latches.

On the opposite side of the door or gate you will have the latch bar (this pivots/hinges from the latch bar plated), the keep which is there to stop the latch bar from dropping too far down and finally the receiver which fixes to the door frame or post and as the name implies receives the latch bar to keep the door shut.

You can usually fit the Suffolk latch wherever you require on the door, however if fitting several Suffolk latches to several doors then you would tend to keep the height of the latches all the same – can look at bit odd if they all differ.

You would also aim to fit the latch onto a stile (vertical upright of a door),  horizontal rail or ledge (horizontal member of a door or gate), if fitting away from a rail (or ledge) then you may need to fit a block to take the Suffolk latch depending on the construction and thickness of the door/gate.

Fit at height that is comfortable for you to operate – you don’t want to be bending all the time or stretching up all the time to open the latch. Anything between waist height and just below the shoulder line would normally be ok.

Traditionally Suffolk latches were always a bit higher up the door than the door handles that you more than likely have in your property today.

• Cordless drill/driver,
• 10mm twist drill,
• 3mm twist drill,
• Square,
• Rule,
• Chisels (1/4”, 1/2”, 3/4”)
• Hammer/mallet,
• Pencil,
• Sandpaper,
• Rounded file

Before we start there are a vast majority of suffolk latches and norfolk latches on the market and all sizes will differ, so you will have to adjust any measurements I use to your own requirements! Everything here is based upon the ornamental Suffolk latch that is available in our shop here First off measure the closing stile (vertical uprights of the door, the closing stile is the one the lock will be on – opposite the hinge side) in width with the door or gate closed whilst standing on the side of the door in direction of closing (see image below as it sounds confusing I know). You measure the visible width of the stile with the door closed (shown as from line A) this is important as you may be closing the door into a rebated frame, if so then you will loose a bit of width from the stile with the door closed. Now mark a vertical centre line (Line C), this is where the centre of the Suffolk latch handle will sit. *If you’re door does not close into a rebated frame then you can work out the centre line of the stile from the edge of the door.

• A – Shows the edge of the door
• B – Visible edge of door when closed
• C – Centre line in width of door stile
• D – Height at which the thumb latch will be
• E – Second horizontal line 25mm below line ‘D’

This is the side that the thumb latch part of the Suffolk latch will sit on.

Next mark a horizontal line at the height that you want the thumb latch to be (line D)

Mark a second line 25mm below this first horizontal line (Shown as E) We are now going to drill a series of 10mm holes on the vertical centre line (C) ,between the two horizontal lines (D & E). These holes go right the way through the door, however drill from both sides of the door to avoid breakout. Use a flat drill or drill bit with a spur on the end and once the drill bit just starts to show on the reverse side stop drilling and complete the hole from the opposite side of the door.

Once you’ve drilled a series of holes, you should have something that looks a bit like this (above right).

It looks a bit messy but we clean this up with a chisel. What you can do first is place your rule vertically up the two edges of the now drilled holes and draw a straight line  on each side – this give you a guideline for straightening up the longer side of the holes.

Score up the edge of the holes using your half inch (12mm) chisel first to avoid any splitting and then carefully chop the waste away (from both sides of the door), only going just over halfway through the thickness of the door.

Personally I wouldn’t bother squaring the top and bottom of the hole, but you can do if you want.

An alternative to squaring the holes up is to leave them rounded (which I think looks better!) and running a rounded file or sandpaper within the top and bottom of the slot to clean them up.

With the Suffolk latch I am using there is a bit of a bulky weld protrusion on the rear so to make sure the Suffolk latch sits flush you need to cut out for these on the door. You only need to do this on the side of the door that the Suffolk latch handle sits on!

We’ve now completed the slot for the lever bar to go through the door. If you’ve got this far then you’re on the home straight now  as there is no more chiselling out to do (unless you need to sink the receiver into architrave on your door frame that is!) – it’s just drilling for screws and screwing the latch and assorted bits onto the door!

Grab the handle of the suffolk latch and sit it onto place on the door. Once in place mark out all screw holes and pre-drill using a 3mm drill bit. Then screw the handle to the door. * If you’ve an architrave in place on the door frame, then you will need to sink the receiver into this onto the door frame! From he reverse of the door we next fit the latch bar. The latch bar wants to fit onto the door so the bar sits horizontal and the lever bar that comes through the door is directly below it.

Whilst holding the latch bar in the correct position, mark out the screw holes and again pre-drill with the 3mm bit. We then fit the receiver. Holding the receiver in place on the door frame or post, drop the latch bar into it and adjust position of receiver so the latch bar is horizontal. Once you are satisfied with the positioning pre-drill all holes and screw into place.  

The next step is to place the keep into position. The keep for want of a better description sits around the latch bar so we need to open the door to slide it over and around the bar. The keep wants to be positioned in such a way that when the door is pushed closed the latch bar engages the receiver and closes into the receiver, place it to high or to low and it will not engage with the receiver

So we position the keep onto the door so as the door loses it engages with the receiver and lifts up and drops into place – to get the correct position for the keep hold it on the door whilst closing the door to check whether it engages and drops into the receiver.

Once your satisifed that the keep is positioned correctly, mark holes and pre-drill and then screw into place. When complete give the door a test by closing it to double check that the latch bar engages and drops into place, if not then adjust as required.

When done, your fitted Suffolk latch should look like the images below.

Rear view of the completed Suffolk latch.

Front view of the fitted Suffolk latch

Then let us know how you got on in the comments below!