The most common and most likely answer to this crossword clue is the 7 plus 8 letter word DRAUGHT EXCLUDER
D
R
A
U
G
H
T
E
X
C
L
U
D
E
R
More clues leading to the result DRAUGHT EXCLUDER
- One often seen lying in doorway is teetotaller?
- Banner supporting old-fashioned potion — it could stop the winter cold
- * The crux – drug deal – disaster
- & 17 Down Bar to current beer supply?
- It helps to insulate Mr Trump’s bone spur
- Current bar that might stop delivery of beer?
- Bar to current beer supply?
Buddy explains!
The straight part
We know that "It helps to insulate" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case it helps to insulate = draught excluder.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.