Name: Perma-Shelter Restorer
Type: PvE/CompetitivePvP/GeneralPvP
Category: Support
Attributes: Restoration 16 (12 + 1 + 3), Communing 13 (12 + 1), Spawning 4 (3 = 1)
Skills Set:
Shelter
Union
Sooting memories
Mend body and soul
Recuperation OR Vengeful Weapon
Life OR Weapon of Warding
Soul Twisting {Elite}
Flesh of My Flesh
Summary: The point of this build is to keep Shelter up at all times so dmg to your party is limited. Put up Life, Union, Recuperation and then kill off Union (which should be close to dead anyway) with Soul Twisting. Then cast Shelter.
When Shelter is about to die, kill it off with Soul Twisting and cast it again.
If Shelter dies too fast for this, kill off Life or Recuperation and then cast Shelter.
Shelter should always be recharged and Soul Twisting should always be active (in your list of 'effects on you' bar) before you cast shelter.
Notes & Concerns:
Secondary Mes with Mantra of Resolve might be better suited for PvP.
Credit: Some guilds I have watched. Can't remember which ones, sry.

ALTERNATE BUILD
Profession: Rit/anything
Name: Perma-Shelter with offense
Type: PvE/CompetitivePvP/GeneralPvP
Category: Support
Attributes: Communing 16 (12 + 1 + 3), Channeling 13 (12 + 1), Spawning 4 (3 + 1)
Skills Set:
Shelter
Pain
Bloodsong
Destruction or Shadowsong
Spirit Rift
Painful Bond
Soul Twisting {Elite}
Flesh of my Flesh
Summary: Again, purpose is to keep shelter up at all times. Destruction therefore is good not because of dmg (you're unlikely to be able to cast it in the middle of enemies and then have them hang around it until 30 secs are gone) but because of its 20 sec recharge. Thus, Destruction followed by Soul Twisting followed by Shelter is your ideal setup.
Spirit rift will give you some aoe dmg. You can do good dmg with this build against high level enemies because of Painful bond.
Notes & Concerns:
Credit: Other posters on Guru and myself.