Any reason I can't make my own door lining from 18mm timber?

[larrylamb11]

I can't buy an off-the shelf door lining the right size to fit an aperture in my old house... its really low and narrow (like 5ft x 2ft) but the wall is thick...
So, I am thinking of buying some of this http://www.diy.com/nav/build/timber...Smooth-Timber-L-2700-x-W-144-x-T-18mm-9275811 (ignore the picture, its the measurements that matter) or some of this http://www.diy.com/nav/build/timber...-PSE-Timber-L-3600-x-W-169-x-T-20-5mm-9275885 and just making a door lining to fit. The advantage with using something like this ^ for me is that the thinner the timber I use the wider the already narrow opening will be....
My only concern is that normal door lining timber is nearly twice as thick and I am guessing this is for a reason! Am I going to cause myself a problem using timber this thin to make a door lining? The door that will eventually be hung is nothing special - just a t&g cottage door, so no great weight and obviously its tiny as well.
What do you think?

 

[big-all]

hinge rebate 2mm leaving only 16mm holding the door
wood yards or builders merchants will have more choice and the basic timber is 3mm thicker

get a larger frame and cut it down or go for a minimum 25mm [ex 1 1/4" from a wood yard]if you go into a wood yard and ask for 5x1" you will get 119mm x 21mm

 

[StephenW]

I don't know the ins and outs but assuming the frame isn't also acting as a lintel, would it be feasable to have a thicker piece of timber for the hinge side and thinner piece for the top and the catch side?

 

[larrylamb11]

There is already a lintel, so thick and thin might work - good idea. I was planning on buying just one piece of wood though. I am going to go to Jewsons over lunch and see what they have....

 

[big-all]

There is already a lintel, so thick and thin might work - good idea. I was planning on buying just one piece of wood though. I am going to go to Jewsons over lunch and see what they have....

ask them to thickness a bit off timber to your needs
this means you will ask for say 25mmx 119mm "actual size"
they will then take a bit off 2x5"[actual size 45mm x119mm ]charge you for that size then thickness down to 25mm assuming they have the machinery

 

[larrylamb11]

OK, been to Jewsons for a look-see..... hefted a bit of 18mm timber and its too thin, as you say... far too wobbly.
Happily they stock 25mm X 175mm planed square edge which will be near enough perfect (although not exactly cheap at £5.70/m ). So I am now thinking I will get a load of this and build a lining from 25mm to suit. How does that sound? Do you think 25mm will be man enough for the job of hanging a (admitedly weedy) door off?

 

[big-all]

you will get a discount off between 20 and 40% dependent on many many factors just be friendly and choose the man with the biggest smile

just check those are actual planed sizes because that is a rough sawn stock size not a normal"finished size" specificly ask "what the finished size is"

 

[larrylamb11]

You are quite right - I just checked, thats a nominal size.... so it would be anything between 4mm and 6mm smaller than that..... hmmmm.... is that going to be too thin then? I must confess it 'looked' and 'felt' about right in terms of sturdiness.
It would be so much easier if they just gave the actual measurements... I am from an egineering background where if something is described as 25mm, it measures 25mm! This business of quoting a size but it not really being that size ain't easy to get one's head around!
Anyway, the question remains as to whether a bit of "25mm" which is actually probably nearer 20mm in reality, would be up to the job....
Amongst their other stock they didn't have any other timber wide enough to carcass my hole (the 'wall' is over 6" thick) other than 32mm X 225mm nosed and tongued window board which would a) have to be cut down and b) was an eye-watering £12.30/m. There wasn't any other stock timber with a greater thickness which came in widths wide enough.

 

[ladylola]

If you are starting off with rough sawn timber at 25mm you could always ask for it to be regulised which means it's just put through a thicknesser and thus only planed on one side. You don't need it planed all round , put the sawn face against the wall. From a 25mm piece you could have it regulised to say 22mm or for that matter it could be just face planed which would probably be the way to go.

 

[larrylamb11]

Job done. Thanks for all the advice, I picked up spme planed 25mm x 175mm timber at Jewsons and built the lining from that. Now its fitted it is good and sturdy as well as being a good size opening in a tight spot. Mission accomplished