Replacing or refurbishing internal 1930s doors

[Lamentable]

Hi, would like some help to understand the best course of action for updating my internal doors.

We currently have probably original "DX30" style internal doors.

Dimensions: 78x30"
Latch height from floor: 127cm / 50"
Latch backset: 76mm / 3"

My questions are as follows:

1. As I understand it these doors don't have tubular latches and have "flat pattern latches". Does this mean I cannot easily fit a rose type door handle as the screws will hit the metal of the latch before going far enough into the door?

2. If I replace the door (see link below), am I able to put the rose door handle at the same height?

The replacement door construction is "Solid Core". I had a carpenter call in today to quote for hanging the doors and he seemed to think that with this type of door they only provide "solid" material at certain points to allow mounting of the handles. Does this sound correct?

3. How many hinges do I need? Tradesperson seemed to think two would be ok, but the door manufacturer specifies three. Guess that answers the question!

Replacement door: https://www.expressdoorsdirect.co.u...internal-doors/dx30s-style-solid-white-primed

Would be grateful for some advice on the best course of action.

Thanks.

 

[KenGMac]

Lamentable, good evening.

First of I have never dealt with these modern versions of this door.

As for

"" "Solid Core". I had a carpenter call in today to quote for hanging the doors and he seemed to think that with this type of door they only provide "solid" material at certain points to allow mounting of the handles. Does this sound correct? ""

The phrase "Solid Core" refers to [at times] what is best called Chip Board material ?

Your Carpenter is correct, in these doors there will be a [so called] lock block, that is a piece of solid actual timber, not the Chip Board material, this allows a lock to be mortised into the door, try cutting a mortise into a bit of Chip board ?? it will not work.,

As for Hinges two will work, three for show, take your pick.

Ken.

 

[Lamentable]

Thanks Ken.

It seems impossible to find out from the manufacturers websites where this lock block occurs in the design. As my latches are currently high up (by modern standards) I would prefer to keep them there to save having to notched out more parts of the door frame.

Is an "engineered" door also made of chipboard?

Guess I will make some phone calls tomorrow to try and find out.

 

[KenGMac]

Is an "engineered" door also made of chipboard?

There are a lot of manufacturers jumping on the band-wagon of "Engineered Timber, or similar" I have the feeling the phrase means only what the manufacture thinks will look good???

As for the Lock block height?
1/. When you get the door, there [should be] a stamp on the top of the door, the top edge.
2/. On the edge of the door there is [depending on maker] an ink stamp indicating where the lock block is and its extent.

OK the above is of no use to you to try to assist in finding the block height? Sorry about that.

Ken.

 

[Deleted member 174758]

Lock blocks are used in hollow core doors which should have enough "meat" in the vertical edge lippings to accommodate the hinges and lock/latch face plate. Lock side should be clearly marked on the top edge

Solid core doors (i.e fire doors) in my experience utilise something like a 10 to 20mm wood lipping on the vertical edges which may comprise 3 to 6mmof visible hardwood and the balance made up of softwood or be all hardwood, but thinner. They do not incorporate lock blocks as their cores are solid chipboard these days. A few (normally 1 to 2 hour externally rated fire doors) can be found with laminboard cores, but these are becoming quite rare

Your problem with 1930s doorways is that they predate the English National Joinery Standards of the late 1940s and may therefore require non-standard size doors

Hinges - three are better as the middle hinge (domestics are top, middle, bottom) can and will limit tendency to warp

 

[JohnD]

you can get hollow doors, but please don't. What use is a door made of air, with a thin skin of ply or hardboard?

Your doors are (about) 6ft 6 ins x 2ft 6 ins which is a perfectly standard size.

Veneered finish, solid core
http://www.premdor.co.uk/internal-doors/shakeroak?doorId=3960

but I can't see a white moulded or paint grade one.

"Engineered" can mean made up with veneered chipboard or with scraps of timber glued together. I'm not keen on it by I suppose it is cheap and seems to work.

If you want, you can get fire doors which are thicker and heavier, and give a better impression of being substantial. They are also much better at blocking sound and, being so solid, they will not give way when a drunk or burglar punches or kicks them.

Because they are heavy and thick, they need a stronger hinge, and often a new door lining (frame)

I have 6-panel fire doors throughout my house, painted not veneered, because I like them (and when it was built, fire doors were required by BRs). They have mortice locks fitted by the carpenter, he seemed used to it.

You can also get solid core doors in the more common 35mm thickness.

Premdor is a popular supplier and found in wickes (may be own-branded)

You can fit tubular latches, which are pierced to allow the screws of standard knobs and handles to be used. The yellow cased Altro seems sturdy and has a nice sprung action.
https://www.ironmongerydirect.co.uk/search?query=tubular latch

You can still get rectangular mortice latches but they are not so common unless you are matching sashlocks.
https://www.ironmongerydirect.co.uk/search?query=flat mortice latch
you can make out they have holes for two screws only. if you use screws with sleeve nuts they will grip through the door and you will not get screws coming loose.

I don't see one with a 3" backset (you don't mean 3" case?) but Imperial Locks still make some old-fashioned lock sizes, as do Willenhall Locks, and Zoo, so if it's important enough, you could probably order them But standard sizes are fairly close. I'd recommend the tubular latch as it will not weaken a thin door so much.

 

[Lamentable]

Thanks all for the replies.

Looking at the spec of the door from Premdor it says:

• Solid Core - Stile and rail construction, ensuring maximum strength between the vertical stiles and horizontal rails.

If I compare that to a white primed one from LPD doors (also available at local distributers) it says:

• This 30's style door is made from a primed solid core in white and features three rectangular inset panels below a larger square panel.

Link: https://www.lpddoors.co.uk/white-dx-30s-style/

So I think these must be similar materials and suitable to have a tubular latch fitted 127cm from the bottom of the door. Does that sound correct?


However, the XL Joinery DX Internal Door says:

• Semi-Solid core door requiring 3 hinges for hanging
  
• Engineered construction for added strength, stability and performance
• In the interest of environmental concerns and improved performance, products contain engineered components including but not limited to laminated timber, MDF or particleboard

Link: https://www.xljoinery.co.uk/WPDX-Product-Dx-Internal-White-Primed-Door


I will call both LPD and XL tomorrow to find out if it is possible to mount the handle where I need it.

 

[JohnD]

from the description, it sounds to me like the LPD might be a "moulded" door, pressed from chipboard.

I think a tubular latch would be best in any of them.

in your style of door, the weakest part will be the large square upper panel, as it is relatively thin and does not have much support.

I have seen such a panel broken and been told that a drunken husband punched through it in a rage.

 

[Lamentable]

I called today to both LPD and a supplier of the doors.

I am informed that the door is made of particle board core and that the handle can be fitted anywhere. The door is of the same material throughout and there is no part of it with a different material.

This indicates to me there is no specific lock block and it should be fine to fit the handle in any position.

I don't know much about different materials but I'm guessing as it is manufactured in this way the handle would be strong enough in any position.

I would welcome you thoughts. Thanks.

 

[foxhole]

The rose is not secured to the door but through it using double ended screws [often supplied with the handles].Pull force is through the handle which clamps to bar thru the door.

 

[Notch7]

Lever handles on a rose backplate are a pain in the arris

especially on chipboard as the backplate screws sometimes pullout Grrr

 

[JohnD]

screw from one side, sleeve nut on the other.

 

[Lamentable]

I've done some investigation on the original doors which I could have dipped or attempt to strip them myself with a heat gun.

They do have a flat mortice latch in them with dimensions as follows:

Depth including front plate: 95mm.
Height (not including front plate): 38mm
Width: 12mm.
Distance to spindle from front plate: 75mm.

It looks a bit like this:

Looking at the handle on a rose design I'm interested in, the rose diameter of 50mm would mean that the screws for the rose back plate could not go very deep before they hit this latch. But does that matter? What keeps the handle on the door? The grub screw to the spindle or the depth of the screws into the wood on the rose fitting?

Last question? Could I replace this latch with a tubular latch?

Thanks again.

 

[Deleted member 174758]

Looking at the handle on a rose design I'm interested in, the rose diameter of 50mm would mean that the screws for the rose back plate could not go very deep before they hit this latch. But does that matter? What keeps the handle on the door? The grub screw to the spindle or the depth of the screws into the wood on the rose fitting?

On traditional doors the grub screw(s), however the rose is fixed using the screws which go through it and as Notch says chipboard core does not give a stable or durable substrate to screw into. This is why modern door sets have a pair of sleeve nuts supplied with them (and to use them your lock or tube latch must have compatible drillings)

 

[JohnD]

The latch case in your picture is pierced to allow two of the long screws to go right through it. But is the one in your door?

If the grubscrews on the spindle are correct, and your pull on the handle on one side is transmitted to the handle on the other side with no pull on the rose or plate, the rose-retaining screws will not be pulled out.

Some knobs or handles are retained into the rose or plate with a circlip, and this type can pull the rose off.