Cutting off the shelf door to size

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Hello,

I’m hoping someone can tell me what to look out for in terms of door type and size if it will have to be cut to size as I can’t find one to fit the existing frame.
The measurement is 28’’ 1/4” (from memory, an old fashioned measurement I have been told)
So if I buy one for the carpenter to fit, what extra width shall I go for or does it not matter so much as anything can be cut down?
It’s for an internal flat door with a glass panel at the top as per pic.

Any pointers appreciated.

Thanks very much!
 

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Ok, thanks. Does it matter if it says “external” or “internal”?
It’s the ground floor flat door in a converted house. Soundproofing is extremely poor and I’m hoping a solid door may help to keep some of the noise out my upstairs neighbours make when thumping past. Might be worth a go.
I’m not clear though if both an internal and an external door can be cut narrower or if there are differences how their ‘insides’ are designed?
P.S. Fire safety comes into this, too, I guess.
 
Then you will need a Fire door. The existing should be a fire door.
 
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fire doors are 44mm thick, which may not fit your existing "frame" unless it has loose stops that can be pried off and re-nailed. Older houses that were built to a high standard may have them worked from the solid. But a new fire-door lining is not expensive. For maximum sound resistance, seal it to the wall with pink fire-foam injected into the gap, and fit the intumescent strips with a furry brush-pile. It's designed to prevent passage of smoke, but it also seals the gap round the door and blocks noise. Purpose-made linings come with a groove for the strip. Quite possibly one was already fitted when the house was converted.

Fire doors are very dense and heavy, and good for blocking sound. Being thick, they will take a mortice lock and/or a nightlatch. However they are usually unglazed. Fire-resisting glass is very expensive. Georgian wired glass was formerly used, I don't know if it is still acceptable.

You can easily get a panelled solid fire door. Due to the weight I strongly recommend hanging it on three lift-off hinges. paint-grade ones are much cheaper than veneered.
 
fire doors are 44mm thick
Actually, John, 30 minute (FD30) fire doors are normally 44mm thick, 1 hour (FD60) fire doors are generally 50 to 52mm thick, but other specs are manufactured and available. The sticker on the top of the edge of the leaf, or the coloured plugs in the same place indicate the actual fire rating, NOT the thickness . It is important to fit a door with the appropriate rating.

For maximum sound resistance, seal it to the wall with pink fire-foam injected into the gap, and fit the intumescent strips with a furry brush-pile.
In point of fact so-called fire foam is AFAIK no longer permissable on its' own in a multiple residency property and the building may well have a document stating what is the minimum requirement (which would be in the possession of the duty holder/landlord/lease-owner). For a 30 minute fire rating this may be 10mm of intumescent sealant beneath the architraves on one side (with the packers cut back 10mm from the surface) and either mineral wool or fire foam beneath that. In the case of 1 hour doors this is doubled-up with 10mm depth of intumescent sealant on both sides in addition to which it is generally a requirement for the hinges (class 11 or 12 fire rated, normally stainless steel, ball bearing - also required on FD30 doors) to be fitted with intumescent hinge pads and for locks and keeps to be wrapped with intumescent paper and fire rated door closers (also required on all fire doors in multiple occupancy buildings) to be insulated from the door by a combination of intumescent paper and intumescent sealant. There is also a requirement that the gapping around the three sides of the door be between 2 and 4mm ONLY (generally checked at 3 to 4 points per side using a taper gauge or brake calliper gauge) and that the gap at the bottom of the door be no more than 4mm at any point when the door closed. If it is more than that then an intumescent drop seal which meets this requirement must be fitted. This may even mean relevelling the door threshold area if the floor in not flat enough.

The "intumescent strips with a furry brush-pile" are combined intumescent strips and cold smoke seals and there are also types with rubber "wiper blade" seals available these days (often used in hospitals). Helps when asking for these things if you know the proper terminology I find

BTW these regs aren't new - they came into force in 2006 and seem to be generally ignored by certain domestic and small scale builders. Where I often work (in commercial/public buildings) they are often being rigorously enforced, and even more so after Grenfell. TBH I find that the average joiner I work with is also completely ignorant of what they are required by law to do when installing fire doors (and yes, I'm a joiner, too, although I also hold a fire door inspection ticket, hence the long response)

Fire doors are very dense and heavy, and good for blocking sound. Being thick, they will take a mortice lock and/or a nightlatch. However they are usually unglazed. Fire-resisting glass is very expensive. Georgian wired glass was formerly used, I don't know if it is still acceptable.
Locks need to be wrapped, as stated above. Night latches are generally very poor in fire doors and ideally should be avoided due to the large void (hole) in the door needed to install them. Glazed doors need to have been tested as such and supplied with the glass fitted (or it can be fitted on-site by the supplier) - you can no longer convert a door on site as that doesn't meet the regs, just as you are given limited leeway on trimming doors to fit openings (manufacturers tend to quote 2 to 5mm trim allowance in my experience). As to Georgian wired, that is no longer permitted (the wire transmits heat through the door) - it is now often replaced by either appropriate fire-rated DG units in intumescent seals or pyro glass, again with appropriate intumescent seals

You can easily get a panelled solid fire door. Due to the weight I strongly recommend hanging it on three lift-off hinges. paint-grade ones are much cheaper than veneered.
Panelled doors need to be specifically fire tested and rated - most aren't. The majority of lift off hinges are most definitely NOT fire rated and must never be fitted to a fire door - doing so will nullify the fire rating of the door. The only permissable hinges on fire doors are now fire rated ones - which are generally stainless steel or in some cases brass or bronze and are invariably ball bearing types (see above)

Sorry, John, but your understanding of fire doors is 15 years or more years out of date. To update yourself why not have a read of this page on the Fire Safety Advice Centre web site which explains the salient points. There's a lot there, but I felt that you original response really warranted some correction and updating, and I hope that you'll find it informative
 
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Thanks, I will have a browse.

Though I will mention that my lift-off hinges are class 11, and stamped.
 
Wow, thanks guys.
I’m uploading a couple of pics of the existing as this may help.
The conversion happened around 1990 so unlikely anything is compliant.
If I go for a glazed fire door, I guess I should be ok?
The existing does have wiring in as you might be able to see.
There is two bits of paneling and I would really like to keep at least one in the door as it will be quite dark otherwise. The existing door is 440mm thick.
My carpenter seems a bit unaware as you say. I haven’t discussed the job in detail though yet with him to be fair.
I’m struggling a little with the terminology, too, to be honest, as English is my 2nd language.
But a lot of good pointers and I will read up some more and hopefully make the right choice.
Is it ok to upload a link to a specific website where I’ve seen a door that may suit?
Thanks again.
 

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Though I will mention that my lift-off hinges are class 11, and stamped.
But just how old are they? The only ones I've used in recent years that were class 11 and lift-off (and we fitted a load in a restaurant last year) were from Carlisle Brass, so not available that readily (we were on 6 weeks delivery). Pretty much all the stuff we get instructed to install is stainless and ball bearing, which is what you'll normally come up with if you Google "Fire Door Hinges"

My carpenter seems a bit unaware as you say. I haven’t discussed the job in detail though yet with him to be fair.
You do need to find out who is the duty holder for the building - this could be the landlord, a housing association, a property management company, etc - so that you can find out what the required standards for new installations are. They may not even have standards, or after Grenfell they may have a fire action and maintenance plan which sets out in detail what is required. What you should not do is just install to the original (out of date) standards without first checking
 
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Bought last year. Mostly branded "Enduromax" though I think some "Eclipse" or "Hi-Load" though they appear identical.

I think Carlisle Brass sell Enduromax at a special (high) price.

I wanted the PVD brass on stainless but they seem to have been discontinued by all brands... which feeds my suspicion that they all come from the same factory.
 
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But just how old are they? The only ones I've used in recent years that were class 11 and lift-off (and we fitted a load in a restaurant last year) were from Carlisle Brass, so not available that readily (we were on 6 weeks delivery). Pretty much all the stuff we get instructed to install is stainless and ball bearing, which is what you'll normally come up with if you Google "Fire Door Hinges"


You do need to find out who is the duty holder for the building - this could be the landlord, a housing association, a property management company, etc - so that you can find out what the required standards for new installations are. They may not even have standards, or after Grenfell they may have a fire action and maintenance plan which sets out in detail what is required. What you should not do is just install to the original (out of date) standards without first checking

Sorry, I should have said earlier, I own the freehold together with the person who owns the upstairs flat.
Her son lives in hers so with a personal arrangement like that there won’t be a rental arrangement, agency or similar.
Don’t think anything is in the lease about fire regs either but will double check.
I have a friend in building control and he might know.
I seem to have just thought of the replacement door measurements and not at all about the fire regulations.
We both work for the local authority so I can find out something, I’m sure.
Thanks again.
 
Not clear why you wish to change , if you swop like for like there will be no improvement in sound insulation, one big problem is the amount of glass in and above the doors .
 
I should have said earlier, I own the freehold together with the person who owns the upstairs flat.
Her son lives in hers so with a personal arrangement like that there won’t be a rental arrangement, agency or similar.
But there will still be a "duty holder" in law - a function probably split/shared between yourself and the owner of the other flat, regardless of whether or not it's in any lease. In general most modern conversions/new builds seem to specify a minimum of FD30 doors as apartment front doors, but in those instances there are specific requirements for non-combustable materials (carpets, wall claddings, etc) in shared/public areas. Your colleague in BC should be able to give you your authorities' take on this (they vary tremendously)
 
Thanks again.
I am now also asking myself if it’s all worth the trouble. I had been thinking to increase security and cover some sound proofing ideally but the longer I think about it, the more I tend to just replace the locks and give it a lick of paint for the time being.
It’s just all been done so cheaply then and I have really loud and unaware neighbours and I don’t really think I’d be making a massive difference. Also don’t want to lose any daylight there.
 

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