1. Acquisition and processing of raw materials: raw materials of kang include all kinds of stones, wood, sand, etc. And the acquisition and processing of these materials need high cost. If some materials are not available locally, they may need to be shipped from other places, which increases the cost.
2. Labor cost: The production of refractory requires skilled craftsmen, which usually requires more labor costs. In addition, some complex fire-resistant designs also need more time and manpower to complete.