Depending on the style of house and interior decoration, there is a huge irony in the history of the use of MDF, timber, plaster and stone, which I give below in a simplified form
Nowadays people look down on MDF because its perceived to be a "cheaper" alternative to timber.
They forget that timber itself was once an easily worked "cheaper" alternative to stonework and plasterwork.
And plaster, so beloved of the Georgian Society, was a far cheaper alternative to paying someone to produce stone carvings!
Many details of interior trims around openings and at the base of walls derive from classical detailing.
These were done first in these islands in stone, in castles, for noblemen and in great country seats and merchants guild halls.
They were based on the Orders of Classical Columns and associated details.
These Orders themselves were refinements over hundreds of years of Greek Temple buildings.
Which originally derived from the simple forms of house built - in timber!
To zero in on one detail, the skirting -
The details of skirtings can be seen to echo the bases of columns and pilasters, in which use the "base" was actually loadbearing.
Skirtings however are fixed to timber grounds to cover up the end between the wall plaster and the floor - they are non-load bearing!
So things change over the years.
Another irony is that timber for interior trim was originally chosen to be painted over, not for the raw timber to be seen.
The importance of timber was that it could offer finely work details with ease of working and relative mass-production - far quicker than stone.
You needed "smooth" timber for this, free from knots and defects, which could be painted over for the perfect modelled finish.
Contrast this with the look at some of the "arts and crafts" style houses in Irish estates.
The bricks are uneven ("rolled" bricks) BE DESIGN - to give a bit of Ye Olde Charactere.
The timbering in such houses may be varnished, unpainted, and chosen for the fact that its riddled with knots.
This gives visual interest to the material, often to the detriment of the shapes of the moulding, the forms of which cannot be followed as easily as painted timbering.
So in one sense, that of a mass produced, moulded, painted component, MDF actually harks back to the first use of timber, affordable modelled surfaces intended to be painted over.
Now my take on this is one that spans over two thousand years in a brief post.
Others may give you chapter on verse on specific derivations of details and how you should treat them.
I'm giving you my two-thousand-year-stare.
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Back to your question.
In terms of your interior, I think you may be looking at this from the wrong angle.
For me. the choice of timber can only be selected after you decide on a strategy for the interior design, otherwise you will be letting a component guide your Master Plan.
Choosing a component before the plan you could end up with a very fussy interior, full of details yet ultimately unsatisfying because it has no overall colour and materials strategy and uses too many different elements which may or may not work well together.
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As one example, classical house design -
You might use a patterned carpet, with curtains in a similar or complementary pattern and shade and a lighter shade again on the walls and ceiling but not the ceiling rose or cornice(s) (if you have such these are normally white).
The strategy for the doors, architraves and skirtings should also be white, in a classical house - these look best with smooth timber substrate, properly sanded and filled, to allow the mouldings, not the patternation of the timber, to be emphasized.
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Another example, arts-and-crafts/ dormer bungalow house design -
You might use sanded- and-sealed floorboards with plain curtains and buff walls - here the timbers may be expressed freely, with staining or clear varnish to express their natural imperfections and even the joinery may be more "rough-and-ready" to support that "rustic" feeling.
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Its the overall look of the house and the ambience of the interior that should lead to the timber choice and even whether its filled and painted over or expressed naturally.
My best advice is that you should consider talking to design professionals like interior designers to guide you on your overall strategy.
After this the part your painted (or varnished, or stained) timbers should play in that strategy may become clearer.
If you just wanted to dip your toe into this world for a nominal amount you could do worse that sit down with someone like Eva Byrne of for an afternoon.
Eva is a colleague of mine with whom I studied Architecture at Bolton Street, otherwise, no connection. Houseology is also on
Facebook.
You asked a deceptively simple question because for me its one of the hardest ones to answer well.
ONQ.
[broken link removed]
All advice on AAM is remote from the situation and cannot be relied upon as a defence or support - in and of itself - should legal action be taken.
Competent legal and building professionals should be asked to advise in Real Life with rights to inspect and issue reports on the matters at hand.