Alright. These bunkers aren't nade proof, and I don't think it's feasible to make a nade proof bunker within a reasonable time limit.
These are pretty sloppy, and the entire thing took me about 10 minutes to build (in between making some dinner and trying to get my wireless network to work), but it can be done much faster.
View from inside the base. It's not multileveled. The panels placed above are to bounce nades away.
Here's a view of the bunker from outside the base. It's a bit hard to tell, but the upper panels are slanted so nades will either bounce oddly or roll back down towards the ground, without making it inside. There's a roof to prevent nades bouncing over and landing on your head.
An attempt at nading the bunker. If someone were to throw it directly through the opening, it'd go too far and leave you undamaged.
Here's shots of entering and standing in the bunker, looking outwards.
This is another bunker I slapped together just to show multiple instances of nade resistance in different types of bunkers. The top two panels are to block nades, I didn't bother putting one on the left side, cause if a player was in a position to throw a nade in from that side, they'd be too close and it'd go too far anyway.
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The slanted roofing/front paneling prevents nades from entering, and protects the shooter more efficiently than a front piece that stands straight up.
On smaller maps like sf_abandon, you can place nade shields all over your base with flat roofing to catch rolling nades. It'd look something like this: \___ but uh, not in text form.
I hope now we wont see anymore of those giant house-like bunkers that are easily naded or destabilized. Get to work!