diff --git a/src/house.h b/src/house.h
new file mode 100644
--- /dev/null
+++ b/src/house.h
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+/* $Id$ */
+
+/** @file house.h definition of HouseSpec and accessors */
+
+#ifndef HOUSE_H
+#define HOUSE_H
+
+#include "strings_type.h"
+#include "cargo_type.h"
+#include "economy_type.h"
+#include "date_type.h"
+#include "house_type.h"
+
+/** Simple value that indicates the house has reached the final stage of
+ * construction. */
+static const byte TOWN_HOUSE_COMPLETED = 3;
+
+enum {
+	HOUSE_NO_CLASS   = 0,
+	NEW_HOUSE_OFFSET = 110,
+	HOUSE_MAX        = 512,
+	INVALID_HOUSE_ID = 0xFFFF,
+
+	/* There can only be as many classes as there are new houses, plus one for
+	 * NO_CLASS, as the original houses don't have classes. */
+	HOUSE_CLASS_MAX  = HOUSE_MAX - NEW_HOUSE_OFFSET + 1,
+};
+
+enum BuildingFlags {
+	TILE_NO_FLAG         =       0,
+	TILE_SIZE_1x1        = 1U << 0,
+	TILE_NOT_SLOPED      = 1U << 1,
+	TILE_SIZE_2x1        = 1U << 2,
+	TILE_SIZE_1x2        = 1U << 3,
+	TILE_SIZE_2x2        = 1U << 4,
+	BUILDING_IS_ANIMATED = 1U << 5,
+	BUILDING_IS_CHURCH   = 1U << 6,
+	BUILDING_IS_STADIUM  = 1U << 7,
+	BUILDING_HAS_1_TILE  = TILE_SIZE_1x1 | TILE_SIZE_2x1 | TILE_SIZE_1x2 | TILE_SIZE_2x2,
+	BUILDING_HAS_2_TILES = TILE_SIZE_2x1 | TILE_SIZE_1x2 | TILE_SIZE_2x2,
+	BUILDING_2_TILES_X   = TILE_SIZE_2x1 | TILE_SIZE_2x2,
+	BUILDING_2_TILES_Y   = TILE_SIZE_1x2 | TILE_SIZE_2x2,
+	BUILDING_HAS_4_TILES = TILE_SIZE_2x2,
+};
+DECLARE_ENUM_AS_BIT_SET(BuildingFlags)
+
+enum HouseZonesBits {
+	HZB_BEGIN     = 0,
+	HZB_TOWN_EDGE = 0,
+	HZB_TOWN_OUTSKIRT,
+	HZB_TOWN_OUTER_SUBURB,
+	HZB_TOWN_INNER_SUBURB,
+	HZB_TOWN_CENTRE,
+	HZB_END,
+};
+assert_compile(HZB_END == 5);
+
+DECLARE_POSTFIX_INCREMENT(HouseZonesBits)
+
+enum HouseZones {                  ///< Bit  Value       Meaning
+	HZ_NOZNS             = 0x0000,  ///<       0          This is just to get rid of zeros, meaning none
+	HZ_ZON1              = 1U << HZB_TOWN_EDGE,    ///< 0..4 1,2,4,8,10  which town zones the building can be built in, Zone1 been the further suburb
+	HZ_ZON2              = 1U << HZB_TOWN_OUTSKIRT,
+	HZ_ZON3              = 1U << HZB_TOWN_OUTER_SUBURB,
+	HZ_ZON4              = 1U << HZB_TOWN_INNER_SUBURB,
+	HZ_ZON5              = 1U << HZB_TOWN_CENTRE,  ///<  center of town
+	HZ_ZONALL            = 0x001F,  ///<       1F         This is just to englobe all above types at once
+	HZ_SUBARTC_ABOVE     = 0x0800,  ///< 11    800        can appear in sub-arctic climate above the snow line
+	HZ_TEMP              = 0x1000,  ///< 12   1000        can appear in temperate climate
+	HZ_SUBARTC_BELOW     = 0x2000,  ///< 13   2000        can appear in sub-arctic climate below the snow line
+	HZ_SUBTROPIC         = 0x4000,  ///< 14   4000        can appear in subtropical climate
+	HZ_TOYLND            = 0x8000   ///< 15   8000        can appear in toyland climate
+};
+DECLARE_ENUM_AS_BIT_SET(HouseZones)
+
+enum HouseExtraFlags {
+	NO_EXTRA_FLAG            =       0,
+	BUILDING_IS_HISTORICAL   = 1U << 0,  ///< this house will only appear during town generation in random games, thus the historical
+	BUILDING_IS_PROTECTED    = 1U << 1,  ///< towns and AI will not remove this house, while human players will be able to
+	SYNCHRONISED_CALLBACK_1B = 1U << 2,  ///< synchronized callback 1B will be performed, on multi tile houses
+	CALLBACK_1A_RANDOM_BITS  = 1U << 3,  ///< callback 1A needs random bits
+};
+
+DECLARE_ENUM_AS_BIT_SET(HouseExtraFlags)
+
+struct HouseSpec {
+	/* Standard properties */
+	Year min_year;                     ///< introduction year of the house
+	Year max_year;                     ///< last year it can be built
+	byte population;                   ///< population (Zero on other tiles in multi tile house.)
+	byte removal_cost;                 ///< cost multiplier for removing it
+	StringID building_name;            ///< building name
+	uint16 remove_rating_decrease;     ///< rating decrease if removed
+	byte mail_generation;              ///< mail generation multiplier (tile based, as the acceptances below)
+	byte cargo_acceptance[3];          ///< acceptance level for the cargo slots
+	CargoID accepts_cargo[3];          ///< 3 input cargo slots
+	BuildingFlags building_flags;      ///< some flags that describe the house (size, stadium etc...)
+	HouseZones building_availability;  ///< where can it be built (climates, zones)
+	bool enabled;                      ///< the house is available to build (true by default, but can be disabled by newgrf)
+
+	/* NewHouses properties */
+	HouseID substitute_id;             ///< which original house this one is based on
+	struct SpriteGroup *spritegroup;   ///< pointer to the different sprites of the house
+	HouseID override;                  ///< which house this one replaces
+	uint16 callback_mask;              ///< House callback flags
+	byte random_colour[4];             ///< 4 "random" colours
+	byte probability;                  ///< Relative probability of appearing (16 is the standard value)
+	HouseExtraFlags extra_flags;       ///< some more flags
+	HouseClassID class_id;             ///< defines the class this house has (grf file based) @See HouseGetVariable, prop 0x44
+	byte animation_frames;             ///< number of animation frames
+	byte animation_speed;              ///< amount of time between each of those frames
+	byte processing_time;              ///< Periodic refresh multiplier
+	byte minimum_life;                 ///< The minimum number of years this house will survive before the town rebuilds it
+
+	/* grf file related properties*/
+	uint8 local_id;                    ///< id defined by the grf file for this house
+	const struct GRFFile *grffile;     ///< grf file that introduced this house
+
+	/**
+	 * Get the cost for removing this house
+	 * @return the cost (inflation corrected etc)
+	 */
+	Money GetRemovalCost() const;
+
+};
+
+extern HouseSpec _house_specs[];
+
+static inline HouseSpec *GetHouseSpecs(HouseID house_id)
+{
+	assert(house_id < HOUSE_MAX);
+	return &_house_specs[house_id];
+}
+
+#endif /* HOUSE_H */