1×7 heart pine lap board ceilings.
60 year old house with wood ceilings, lap board, but time has caused gaps between the boards. How can I seal between these boards and keep the natural finish? Gaps range between 1/16 and 3/8. Right now my heat is pouring into the attic.
You could use colored wood putty. It is available as an oil based or water based putty plus many colors that are designed to match both stained and natural woods. This will work with most gaps but might not work as well with the widest 3/8 inch gaps but worth trying.