I have found a method of mapping that should make it rather easy(and fast) to create house-based,simple maps.
i do this via a little nary unknown game called The Sims 2.
The method involves a sort of modular application of cubes,example 1 tile in Sims is equal to a 256x128x128 cube,add the math together to create larger rooms,for walls use cubes in say 256x128x8 or 256x8x128(depending on the wall's facing) and add them in appropriately.Floors and stairs i still have to figure out,but i can tell you that from what i remember(not totally sure)there are 18 steps per standard staircase.

I have played my own custom map designed off of my very own house and i can tell you that house based maps are very fun,especially on Ballistic Conflict.

Yeah, I've found that some maps that don't play particularly well in stock UT (close-quarters, cramped maps) play quite well in BW.

Your map though: Is it one of those giant maps? Or is this more life-sized?

It is life sized(for the most part rooms are not perfect and each room is taller),and has 3 levels(floors),the basement ground level and second story.I designed a second version to play specifically Conflict,one team deep in the basement,the other on the second floor.There is only one way upstairs and two ways downstairs,but the basement has more defensible positions(namely on top of my wood burner where a machine gun can be mounted ).It ends up that both teams regularly smash up in the kitchen .

Main reason that BW plays better on small cramped maps,by my opinion is because of shotguns,melee,and cover,allowing more tactics and surprises.

Curse4 is a good example of a practically 'made for BW' map,throw some zombies in there and watch them swarm in the pit

my brother loves making life sized maps.

He lately had been working on DM-PJ-DownTown. Which is awesome with ballistic. I added the feature of shooting down every window with glass particles! As ballistic weapons can go trough small walls, my brother has kept that in mind while designing the map. The SRS 9000 assault rifle can punch trough most walls in that map.

The map is simple, its apparments, a bar and a shop next to a street.
Inspired by Max Payne (one piece of map) it is truely fit for BW and not all too awesome for normal UT2004 weapons.

Awesome.
The only weapon i knew of that could go through walls was the Railgun.What thickness lies just above the point where most 'high power' guns can punch through?

Don't quote me on this, but I think the SRS900 goes through 64 if I remmmber right. Other guns usually pierce through 32. I can't remmbember what topic I read this from, though....

I think you should halve those numbers

Something like 32 for SRS
and 16 for regular.

I'm gonna make a quick test map for testing sometime
Not now, editor on this PC is busted. Glad I got another one ^^