What is the best way to insulate the drywall from behind our wood burning stove? There are heat resisting drywall and insulated panels that can be attached to drywall. I don't kno0w what would be best. - Ding
Welcome to the community and thanks for asking a great question.
I grew up in a older house that had a wood burning stove and we were fortunate enough to have our stove put inside an existing old stone fireplace. Placement and clearance are going to be the keys here, as well as features that the specific model of your fireplace actually has. With that said, check your owners manual for any details that give out exact clearance from the wall as well as information regarding rear dedicated stove shields, which can make insulating the wall from behind less of a chore.
Luckily, placing a heat shield to insulate the wall behind your stove isn't a hard task nor are you limited to a few options. You can pick from your choice of various materials such as sheet metal, cement-based backerboard (like WonderBoard, HardieBacker or Durock), or heat-resistant paneling. The key here to make it work though is SPACING.
The new protected wall is one where a non-combustible shield is placed a minimum of 1” away from the wall, and allows air to flow unimpeded from the bottom to the top. Non-combustible spacers are used to attach the shield to the wall. The most commonly used spacers are made of metal and/or ceramic and are available at your local home center, personally I like using metal screws with metal anchors. The spacer acts as a "breezeway" if you will of allowing airflow behind the existing wall to keep cool by allowing air to pass through it. Just as double wall pipe inside acts as a guard from heat going out of your stove in the walls, the spacing helps reduce the heat down from the stove, and with the right options, you can make it look good as well.
Below are some diagrams showing how spacing is done, place the spacers on center studs, and you should have a nicely insulated wall:
Thanks again for your question and if you need further assistance, the community and I are always here to help.