Reach attacks with monsters

[montoya]

I'm curious monsters that have say 15 foot reach, are they hamped by the reach weapon limitations? For example if the PCs are in combat with something that has 15ft reach would the monsters attacks be negated if they were in base contact? Does the monster have to be at 15ft to attack?

[AlanBruce]

If a monster has 15ft. reach, he can attack enemies 15ft. away and enemies adjacent to it.

If the monster has 15ft. reach and a weapon (say, a longsword), their reach would extend an extra 5ft., but the damage would be that of the weapon, not his natural attack ( I am assuming your monster has natural attacks if it has a 15ft. reach).

I am sure there is a more definitive RAW answer, but that's how I have ran it in my games- then again, I usually use monsters that have at least 10ft. reach and give them spiked chains to cover as much distance as they can.

[Zombimode]

If the monster has 15ft. reach and a weapon (say, a longsword), their reach would extend an extra 5ft., but the damage would be that of the weapon, not his natural attack ( I am assuming your monster has natural attacks if it has a 15ft. reach).

This is not true. Only weapons with the reach special increase the reach of a creature. A fire giant without manufactured weapons has a reach of 10 ft. and can attack targets with its slam that are one or two squares away (with the exception of the four out-most corners which are NOT covered by 10 ft. natural reach; small or medium creature with reach weapons are the exception).
If he picks up his large greatsword he still has a reach of 10 ft. with the sword.

[montoya]

We have been doing at if a creature has reach it cannot attack inside its range. I guess we are wrong.

[Zombimode]

Yes, natural reach does not create save spaces. In other words, a higher natural reach is purely an upside.

[Firest Kathon]

The rules are in the combat (http://www.d20pfsrd.com/gamemastering/combat#TOC-Big-And-Little-Creatures-In-Combat) chapter.

Unlike when someone uses a reach weapon, a creature with greater than normal natural reach (more than 5 feet) still threatens squares adjacent to it. [...] Large or larger creatures using reach weapons can strike up to double their natural reach but can't strike at their natural reach or less.