Sorry I'm new to this and trying to start my own server I'd like to buff all foundations walls doors and stone high walls but im not sure how to do it can someone please help ?

Do you want floors, roofs, stairs, other, TC?  1 = normal damage.  0 = no damage.   2 = double damage, 0.5 = half damage.

There are the main building settings:

  "Building": {
    "AllowDecay": "true",
    "ModifyBarrel": 1.0,
    "ModifyDeployed": 1.0,
    "ModifyDoor": 0.0,
    "ModifyFloor": 1.0,
    "ModifyFoundation": 0.0,
    "ModifyHighExternal": 0.0,
    "ModifyOther": 1.0,
    "ModifyRoof": 1.0,
    "ModifyStairs": 1.0,
    "ModifyToolCupboard": 1.0,
    "ModifyWall": 0.0
  },
  "Building_Grade_Multipliers": {
    "Metal": 1.0,
    "Stone": 1.0,
    "TopTier": 1.0,
    "Twigs": 1.0,
    "Wood": 1.0
  },​

You can ignore the time modifiers.  You can alter the damage from specific sources:

"BuildingBlock_Multipliers": {
"antivehicle": 0.0,
"arrow": 0.0,
"bite": 0.0,
"bleeding": 0.0,
"blunt": 0.0,
"bullet": 0.0,
"cold": 0.0,
"coldexposure": 0.0,
"decay": 1.0,
"drowned": 0.0,
"electricshock": 0.0,
"explosion": 0.0,
"fall": 0.0,
"generic": 0.0,
"heat": 0.0,
"hunger": 0.0,
"poison": 0.0,
"radiation": 0.0,
"radiationexposure": 0.0,
"slash": 0.0,
"stab": 0.0,
"suicide": 0.0,
"thirst": 0.0
},
"Bypasses": {
"Heli_bypass": "false"
},

That last one determine if the heli will bypass protection (False = heli is affected by settings, True = heli will rip buildings apart).

Merged post

Note the setting are zero for sources as I did not set them back to 1 as I copied this from a PVE server.

thanks a lot 

Do you need any further assistance?