Interior kiln coating
Products to use as a sealer over OSB. October 9, 2002
What do you use for coating the interior of your kiln? We will be using OSB and need a good sealer.
Conventional asphalt-based kiln coatings will work fine on OSB as well as other wood and/or metal surfaces in the kiln.
You can get them with or without aluminum and fibers; if the darkness doesn't bother you, the black coatings work just fine. Aluminum may look better and will reflect some light when you're in the kiln with a flashlight.
The key as with any paint job is a clean, dry surface. These coatings can be brushed or rolled on, or sprayed on for large projects (although spraying requires some pretty serious equipment). If you have steel components in the kiln, be sure they have a good primer coat on before the kiln coating goes on.
From contributor D:
Fibered aluminized metal roof coating sold in any lumber yard is fine (trailer roof coating).
The specialized coatings that the kiln manufacturers use or recommend are able to withstand the long periods of intense heat, humidity, and acidic environment better than the standard trailer coatings will provide.
If you have steel components, it is worth the time to do a good surface prep, and pay a few extra bucks on coatings. Let me mention surface prep again. Without good prep, it does not matter what you put on.
From contributor D:
There is no difference in how roof coatings and kiln coatings are made. There are different grades in both but the stuff is the same, different label, different price. Some companies make the same exact product and charge by which label they put on the can. You can buy good in both and crap in both. I've done both. I assumed because you were coating OSB, it was a relatively small kiln and you probably could not justify the expense of the difference between shipping costs etc.
From the original questioner:
We are putting in a Nyles 200 unit. The room is 17'x12'x8'. Walls will be 8" thick with two layers of continuous 2" extruded polystyrene with one layer of 1.5" extruded polystyrene cut between the studs, then the inside is 6 mil vapor barrier and 7/16 OSB. The same with the ceiling. Temps should only hit 150 or so, max. I was thinking of using the white elastometric coating made by Black Jack.