diff --git a/include/coreinit/expandedheap.h b/include/coreinit/expandedheap.h
index 90e7222..2a532db 100644
--- a/include/coreinit/expandedheap.h
+++ b/include/coreinit/expandedheap.h
@@ -11,57 +11,104 @@
 extern "C" {
 #endif
 
-typedef struct MEMExpandedHeap MEMExpandedHeap;;
+typedef struct MEMExpandedHeap MEMExpandedHeap;
+typedef struct MEMExpandedHeapBlock MEMExpandedHeapBlock;
+typedef struct MEMExpandedHeapBlockList MEMExpandedHeapBlockList;
 
-struct MEMExpandedHeap
-{
-};
-UNKNOWN_SIZE(MEMExpandedHeap);
-
-typedef enum MEMExpHeapMode
+typedef enum MEMExpandedHeapMode
 {
    MEM_EXP_HEAP_MODE_FIRST_FREE     = 0,
    MEM_EXP_HEAP_MODE_NEAREST_SIZE   = 1,
-} MEMExpHeapMode;
+} MEMExpandedHeapMode;
 
-typedef enum MEMExpHeapDirection
+typedef enum MEMExpandedHeapDirection
 {
    MEM_EXP_HEAP_DIR_FROM_TOP        = 0,
    MEM_EXP_HEAP_DIR_FROM_BOTTOM     = 1,
-} MEMExpHeapDirection;
+} MEMExpandedHeapDirection;
+
+struct MEMExpandedHeapBlock
+{
+   uint32_t attribs;
+   uint32_t blockSize;
+   MEMExpandedHeapBlock *prev;
+   MEMExpandedHeapBlock *next;
+   uint16_t tag;
+   UNKNOWN(0x02);
+};
+CHECK_OFFSET(MEMExpandedHeapBlock, 0x00, attribs);
+CHECK_OFFSET(MEMExpandedHeapBlock, 0x04, blockSize);
+CHECK_OFFSET(MEMExpandedHeapBlock, 0x08, prev);
+CHECK_OFFSET(MEMExpandedHeapBlock, 0x0c, next);
+CHECK_OFFSET(MEMExpandedHeapBlock, 0x10, tag);
+CHECK_SIZE(MEMExpandedHeapBlock, 0x14);
+
+struct MEMExpandedHeapBlockList
+{
+   MEMExpandedHeapBlock *head;
+   MEMExpandedHeapBlock *tail;
+};
+CHECK_OFFSET(MEMExpandedHeapBlockList, 0x00, head);
+CHECK_OFFSET(MEMExpandedHeapBlockList, 0x04, tail);
+CHECK_SIZE(MEMExpandedHeapBlockList, 0x08);
+
+struct MEMExpandedHeap
+{
+   MEMHeapHeader header;
+   MEMExpandedHeapBlockList freeList;
+   MEMExpandedHeapBlockList usedList;
+   uint16_t groupId;
+   uint16_t attribs;
+};
+CHECK_OFFSET(MEMExpandedHeap, 0x00, header);
+CHECK_OFFSET(MEMExpandedHeap, 0x40, freeList);
+CHECK_OFFSET(MEMExpandedHeap, 0x48, usedList);
+CHECK_OFFSET(MEMExpandedHeap, 0x50, groupId);
+CHECK_OFFSET(MEMExpandedHeap, 0x52, attribs);
+CHECK_SIZE(MEMExpandedHeap, 0x54);
 
 MEMExpandedHeap *
-MEMCreateExpHeapEx(MEMExpandedHeap *heap, uint32_t size, uint16_t flags);
+MEMCreateExpHeapEx(MEMExpandedHeap *heap,
+                   uint32_t size,
+                   uint16_t flags);
 
 MEMExpandedHeap *
 MEMDestroyExpHeap(MEMExpandedHeap *heap);
 
 void *
-MEMAllocFromExpHeapEx(MEMExpandedHeap *heap, uint32_t size, int alignment);
+MEMAllocFromExpHeapEx(MEMExpandedHeap *heap,
+                      uint32_t size,
+                      int alignment);
 
 void
-MEMFreeToExpHeap(MEMExpandedHeap *heap, uint8_t *block);
+MEMFreeToExpHeap(MEMExpandedHeap *heap,
+                 uint8_t *block);
 
-MEMExpHeapMode
-MEMSetAllocModeForExpHeap(MEMExpandedHeap *heap, MEMExpHeapMode mode);
+MEMExpandedHeapMode
+MEMSetAllocModeForExpHeap(MEMExpandedHeap *heap,
+                          MEMExpandedHeapMode mode);
 
-MEMExpHeapMode
+MEMExpandedHeapMode
 MEMGetAllocModeForExpHeap(MEMExpandedHeap *heap);
 
 uint32_t
 MEMAdjustExpHeap(MEMExpandedHeap *heap);
 
 uint32_t
-MEMResizeForMBlockExpHeap(MEMExpandedHeap *heap, uint8_t *address, uint32_t size);
+MEMResizeForMBlockExpHeap(MEMExpandedHeap *heap,
+                          uint8_t *address,
+                          uint32_t size);
 
 uint32_t
 MEMGetTotalFreeSizeForExpHeap(MEMExpandedHeap *heap);
 
 uint32_t
-MEMGetAllocatableSizeForExpHeapEx(MEMExpandedHeap *heap, int alignment);
+MEMGetAllocatableSizeForExpHeapEx(MEMExpandedHeap *heap,
+                                  int alignment);
 
 uint16_t
-MEMSetGroupIDForExpHeap(MEMExpandedHeap *heap, uint16_t id);
+MEMSetGroupIDForExpHeap(MEMExpandedHeap *heap,
+                        uint16_t id);
 
 uint16_t
 MEMGetGroupIDForExpHeap(MEMExpandedHeap *heap);
@@ -72,7 +119,7 @@ MEMGetSizeForMBlockExpHeap(uint8_t *addr);
 uint16_t
 MEMGetGroupIDForMBlockExpHeap(uint8_t *addr);
 
-MEMExpHeapDirection
+MEMExpandedHeapDirection
 MEMGetAllocDirForMBlockExpHeap(uint8_t *addr);
 
 #ifdef __cplusplus