in cold weather at times it takes about a half hour or more to get heat on 2005 Buick Terraza

this only happens in very cold weather

2 answers 2 comments
Have thermostat checked, possible thermostat not allowing coolant to warm as quick, noticed more in colder weather.
Thank you but I had this done also coolent flush still had problem would starting it up with the heating control in the windshield vent lower heat control the second from the last control position have any thing to do with it? thanks
AGREE WITH #1 ALSO CK COOLANT LEVEL
THANK YOU ALL JUST GOT THE TERRAZA BACK FROM REPAIR THEY TOLD ME TO ALWAYS START IT UP WITH THE HEAT CONTROL ALL THE WAY TO THE RIGHT TO DEFROST POSITION SO FAR SO GOOD REGARDS AN MERRY CHRISTMAS