Walls and Doors - Mega Dungeon Detail on the Cheap.

Back when I was running ASE I discovered that while the room descriptions and details are very functional and describe the rooms sufficiently for the mechanical aspects of play they often lacked the sorts of details my players wanted to know.  Specifically, one of my players kept wanting to know about the walls and doors: material, age, markings, dust.  While a decent GM can usually provide this sort of thing quickly - and if it's unavailable, one must wonder how well the GM is visualizing the fantasy spaces he is creating, it becomes tricky at times, especially in a megadungeon setting where there are plenty of corridors and empty rooms.  

This could be a dungeon hallway

Another Narrow Hallway

Full description for every surface and object in a dungeon is likely impossible, but also onerous for the GM, boring for the players and the death of any published setting. At the same time setting detail is important, as landmarks and detail is one of the best ways to evoke scene. There is a huge difference to visualizing one's character walking down an arched hall with a low 7' ceiling made of rough, moss covered stone that drips constantly and visualizing her walking through halls with 30' ceilings made of perfectly joined, dusty, monumental sandstone blocks. One expects different encounters and dangers in these two 10' wide corridors, and without some detail, the mazes of 10' halls and small rooms that make up most classic dungeons become pointless mapping exercises,
eliminating a lot of the fun of exploration.  Additionally, in classic exploration scenarios, where random encounters provide a major challenge, the environment - lighting, odors, wall material and most importantly door material, actually effect play.  Slick floors may impede melee, low ceilings ranged attacks, weak walls provide ambush opportunities, and strong doors facilitate retreat.

More classic dungeon hallway perhaps?

Finally a good GM should be able to answer questions about the environment from players.  While the answers may be boring (i.e. the walls are stone blocks and seem sturdy) these answers inform the sort of interesting and creative solutions that make table top games interesting compared with computer games. It's not always easy to think of the nature of a wall or space on the fly, and more important it's not also helpful.  Variation and odd results can make a dungeon more interesting, and especially when the GM is using the sort of minimally described spaces popular in one page dungeons, early modules or published megadungeons.

Torn between wanted to avoid excessive description, and wanting to provide evocative spaces for exploration that make it easier to visualize the adventure in a cinematic fashion, I've adopted a few simple tables for the Apollyon that I use to describe spaces when the party blunders off my maps or into sketchily detailed areas.  For example, I have a D6 table for what infests the area (1- Vermin, 2- Horrors, 3 - Undead, 4- Devils, 5- Robots, 6- Humanoids) so random encounters and room uses make sense.  Better though is the following wall description table, there's another for doors (but it includes some traps and lock mechanisms so I am hiding it for now).  What's key about the wall table is that it fits with my setting, and I think I'd have to write a few different ones for various areas of the ship (cabins, industrial areas or crew areas for example), but the one below works generally. For me this is a good investment of time, and I think similar tables would be a good investment in a published megadungeon setting.

D20	Wall Material	Additional details
1	Metal Panels, painted to resemble wood	Water damaged, salt stained
2	Thin wood veneer	Water logged
3	Lathe and plaster	Sooty, burnt
4	Painted metal	Ornate moldings and plaster decorations
5	Heavy wooden beams and boards	Hastily patched or repaired
6	Ceramic tiles over metal	Scrubbed clean
7	Metal panels	Scratched and gouged
8	Riveted metal	Covered in lichens or fungus
9	Heavy Cast metal	Marked with arrows, murals or signage
10	Plastered	Gnawed by vermin
11	Wall papered	Graffiti covered
12	Velvet or silk wallpaper	Rusted or dry rotted
13	Cast ceramic molded over metal	With bolt holes for missing furnishings or machinery
14	Covered in peeling wall paper	Pasted with handbills
15	Encrusted in filth too deep to know	Engraved or cast with relief
16	Metal with marble tile	Peeling paint
17	Leather upholstered	Odd crystal growths
18	Sheet Rock over metal beams	Portholes and armored glass panels
19	Riveted metal	Filigree work
20	Metal panels	Slicked with oil