Smoke (light & white, drifting at the ceiling level in a haze to start, then billowing plumes darkening to sooty black as plastics, oils, chemicals, varnish and paint etc are consumed), flame, coals, flames licking the walls and sweeping across the ceiling, fire ropes chewing through curtains, spreading across the floor in fiery sheets, bottles of liquid exploding due to heat and pressure, windows bursting, roof beams caving in, flashes as combustibles explode, timbers charring and blackening, smoke haze coating the room, sparks drifting down and swirling in the air drafts, ash drifting down, bits of curtains crumbling, electrical flickering and then shorting out, patches of carpet melting, plastics shrinking, melting and discoloring, wood charring & bending, stair spindles turning into pillars of flame, metal becoming red hot, furniture becoming beds of fire, light fixtures falling from the ceiling, smoke curling beneath closed doors, people crawling along the floor, gasping for breath, trying to find an exit, firemen with oxygen tanks strapped to their back, hoses, water dousing flames, creating water vapor, snuffing out fire and leaving behind blackened stumps, shattered glass and splintered wood, liquid flaming drops of plastic dripping or leaking in a slim stream from a plastic object, a flickering orange glow, the welcome silhouette of a firefighter striding through the haze
The crackle of flame, the woof sound as something catches fire quickly, plastics melting and dripping into hissing puddles, the creak and groan of timbers contracting, cries for help, glass breaking, roof caving in, floor groaning, someone banging on a door, shouting out a window, crying, gasping for breath, coughing uncontrollably, furniture/doors/stairs shifting, tables collapsing with a crash as legs become charred stumps unable to hold the weight of the tabletop, exploding glass, windows shattering, the hiss/squeal of liquids turning to steam, firemen smashing down the door, tromping through debris, the fire alarm blaring, sirens outside blaring, shouts, axes cutting through walls, smashing down doors, lights crashing to the floor or smashing through from the floor above, curtain rods clanging to the ground, screams, the pop of the glass inside picture frames splintering from the heat
Smoke will pick up the smells of what's burning and at what stage. Walls, wooden furniture, etc will have a smokey campfire-ish smell at first, plastics a sharp, acrid smell that will burn the nose and throat, but as the fire progresses the smoke will grow increasingly toxic causing instinct to kick in, giving way to flight, not fight.
Gummy, acrid ash coating the tongue, phlegm, the occasional gulp of fresher air if leaning out a window to breathe on a second story or above window
rubble underfoot, cutting feet on glass or wood splinters, searing burns, intense heat, blistering palms from touching something too hot, pressing a towel or shirt to the mouth and nose in an attempt to breathe cleaner air, wrapping shirts around hands to protect them, fumbling down halls on hands and knees, collapsing to the ground from smoke inhalation, shoving or ramming a blocked door with the shoulder, pulling/pushing debris out of the way, stumbling down stairs, past furniture, bashing into furniture in the smokey haze, clinging to and pulling loved ones, carrying children in arms, wrapping loved ones in wet towels or blankets, smashing a window to escape, raw throat and nose, lungs burning, wheezing breath ripping at throat, doubling over coughing, burns on the hands, pounding weakly at a door, tears carving tracks through soot on face, intense heat on skin, sweat, fatigue, slapping at sparks that burrow into clothing, putting them out
--The words you choose can convey atmosphere and mood.
I crammed myself tight into the corner so the flames couldn't find me. Mr. Bear's hard plastic nose dug into my chest but I didn't dare loosen my grip on him. Across from me, the dolls on my shelf began to change, their fine blond ringlets shrinking into black frizz and then crumbling into dust. They stared at me, black bristles poking out their heads, their smiling faces shifting and drooping, crying plastic tears. I pushed my face into the soft fur of Mr. Bear and pretended I was at Grandma Hiller's, hiding in the linen cupboard, waiting for her to find me.
Even from across the cul-de-sac, the brightness was enough to force my eyes into a squint. Water from the fire fighter's hoses arced across the night sky and splattered across the charred shingles, doing little to quench the flames consuming the house. I picked out the owners, standing in the lee of a fire truck, their soot-stained faces upturned, watching the black column rising up from the inferno, taking their hopes and dreams with it.
--Similes and metaphors create strong imagery when used sparingly.
Example 1: (Simile)
As Mary lay there, her face pressed to the warm floor boards, she pulled in a final, reedy breath. Time slowed, and darkness began to close in on her like the heavy velvet curtains that signalled the end of a theatre performance.
Example 2: (Metaphor)
I paced the street, clutching at the medic blanket draped around my shoulders. Beneath it, worry and fear clung to my skin in a sooty sweat. The firefighters would find Mark. They had to.