Answer:

insulate

Answer	Crossword Clue
INSULATE	Prevent heat transmission
INSULATE	Weatherize, as with fiberglass
INSULATE	Protect against heat loss, say

INSULATE	Protect
INSULATE	Make heatproof
INSULATE	Protect from heat loss
INSULATE	Shield
INSULATE	Set apart.
INSULATE	Set apart
INSULATE	Protect against cold
INSULATE	Beat the heat or cold

INSULATE	Take steps to keep the house warm
INSULATE	Wrap in fiberglass
INSULATE	Put fiberfill in, e.g
INSULATE	Install fiberglass, perhaps