Mushure mekunge magonhi egirazi akayerwa nemoto aratidzwa kune tembiricha yepamusoro, iyo inoonekera jelly-yakafanana nemoto glue layer iri pakati pegirazi inoomesa nekukurumidza, ichigadzira opaque fireproof insulation board. Gonhi regirazi risina moto ndiro gonhi regirazi rakachengetedzeka. Kuoma kwegirazi rinodzivirira moto 6-12 nguva yegirazi rinoyangarara; iri 2-3 nguva yegirazi rakanyoroveswa.