Window frame needs front of seasoned wood (4)
I believe the answer is:
sash
'window frame' is the definition.
(I've seen this before)
'front of seasoned wood' is the wordplay.
'front of' indicates taking the first letters (the letter at the front of the word).
'wood' becomes 'ash' (wood from an ash tree).
The initial letter of 'seasoned' is 's'.
's'+'ash'='SASH'
'needs' is the link.
(Other definitions for sash that I've seen before include "seen hanging around Miss World?" , "Popular band in Northern Ireland" , "Baldrick" , "Band - scarf" , "(Uniform) strip; window-frame" .)