diff --git a/packages/shared/src/errors/error-codes.ts b/packages/shared/src/errors/error-codes.ts
index b245726..d70609d 100644
--- a/packages/shared/src/errors/error-codes.ts
+++ b/packages/shared/src/errors/error-codes.ts
@@ -14,6 +14,8 @@
  * code families —
  *   - `4000`–`4099`: request validation
  *   - `4010`–`4019`: authentication
+ *   - `4020`–`4029`: conflicting/invalid state transition
+ *   - `4030`–`4039`: authorization (caller authenticated, but not allowed to)
  *   - `4040`–`4049`: not found
  *   - `5000`–`5099`: internal/unexpected
  *
@@ -32,6 +34,10 @@ export enum ErrorCode {
   INVALID_CREDENTIALS = 4010,
   /** Request required a session cookie/JWT that is missing, invalid, or stale. */
   NOT_AUTHENTICATED = 4011,
+  /** `POST /house` or `POST /house/join` attempted while the profile already belongs to a household. */
+  ALREADY_HAS_HOUSE = 4020,
+  /** A household action reserved to its admin (delete the household, remove a member) attempted by a non-admin member. */
+  NOT_HOUSE_ADMIN = 4030,
   /** No route/resource matches the request. */
   NOT_FOUND = 4040,
   /** The profile making the request has no household yet (`houseId` is `null`). */
@@ -40,6 +46,8 @@ export enum ErrorCode {
   DIET_NOT_FOUND = 4042,
   /** One or more `allergyIds` don't match any reference `Allergy` row. */
   ALLERGY_NOT_FOUND = 4043,
+  /** `POST /house/join`'s `inviteCode` doesn't match any household. */
+  INVITE_CODE_NOT_FOUND = 4044,
   /** Unexpected/unhandled failure — the catch-all, always logged server-side. */
   INTERNAL_ERROR = 5000,
 }
diff --git a/packages/shared/src/index.ts b/packages/shared/src/index.ts
index 8f20709..95aa7b9 100644
--- a/packages/shared/src/index.ts
+++ b/packages/shared/src/index.ts
@@ -4,6 +4,7 @@
 // detail specific to one side.
 
 export * from "./errors/error-codes.js";
+export * from "./schemas/account.js";
 export * from "./schemas/auth.js";
 export * from "./schemas/household.js";
 export * from "./schemas/profile.js";
diff --git a/packages/shared/src/schemas/account.ts b/packages/shared/src/schemas/account.ts
new file mode 100644
index 0000000..a8a9f77
--- /dev/null
+++ b/packages/shared/src/schemas/account.ts
@@ -0,0 +1,15 @@
+import { z } from "zod";
+
+// See schemas/auth.ts for the shared client/server validation rationale.
+
+/**
+ * Payload accepted by `DELETE /auth/me`. Deleting an account is
+ * irreversible, so it's gated behind re-entering the current password —
+ * same idea as `loginSchema`'s password field (presence only, the API does
+ * the real `argon2.verify`), not a fresh set of complexity rules.
+ */
+export const deleteAccountSchema = z.object({
+  password: z.string().min(1, "Le mot de passe est requis"),
+});
+/** Inferred TS type for {@link deleteAccountSchema}'s validated output. */
+export type DeleteAccountInput = z.infer<typeof deleteAccountSchema>;
diff --git a/packages/shared/src/schemas/household.ts b/packages/shared/src/schemas/household.ts
index bd138aa..df95e94 100644
--- a/packages/shared/src/schemas/household.ts
+++ b/packages/shared/src/schemas/household.ts
@@ -10,3 +10,17 @@ export const renameHouseSchema = z.object({
 });
 /** Inferred TS type for {@link renameHouseSchema}'s validated output. */
 export type RenameHouseInput = z.infer<typeof renameHouseSchema>;
+
+/** Payload accepted by `POST /house` — same naming rule as renaming one. */
+export const createHouseSchema = z.object({
+  name: z.string().trim().min(1, "Le nom du foyer est requis").max(100),
+});
+/** Inferred TS type for {@link createHouseSchema}'s validated output. */
+export type CreateHouseInput = z.infer<typeof createHouseSchema>;
+
+/** Payload accepted by `POST /house/join`. Invite codes are always 8 characters — see `house.service.ts`'s generator. */
+export const joinHouseSchema = z.object({
+  inviteCode: z.string().trim().length(8, "Le code d'invitation doit contenir 8 caractères"),
+});
+/** Inferred TS type for {@link joinHouseSchema}'s validated output. */
+export type JoinHouseInput = z.infer<typeof joinHouseSchema>;
diff --git a/packages/shared/src/types/household.ts b/packages/shared/src/types/household.ts
index 32b7c93..d519ede 100644
--- a/packages/shared/src/types/household.ts
+++ b/packages/shared/src/types/household.ts
@@ -1,9 +1,27 @@
 /**
- * A household, as returned by `GET /house/current` / `PATCH /house/current`.
- * Unlike `DietView`/`AllergyView` this isn't reference data — it's the
- * current user's own household.
+ * One member of a household, as embedded in {@link HouseView}. Deliberately
+ * a small subset of `SafeUserProfile` — just enough for the household
+ * settings page's member list (name + who's the admin), not the member's
+ * own email/diet/etc.
+ */
+export interface HouseMemberView {
+  id: number;
+  firstName: string;
+  lastName: string;
+}
+
+/**
+ * A household, as returned by `GET /house/current` / `PATCH /house/current`
+ * / `POST /house` / `POST /house/join`. Unlike `DietView`/`AllergyView`
+ * this isn't reference data — it's the current user's own household.
  */
 export interface HouseView {
   id: number;
   name: string;
+  /** FK to the member who administers this household (created it, or inherited adminship — see `house.service.ts`'s `leaveCurrentHouse`). */
+  adminId: number;
+  /** Shareable code another user enters via `POST /house/join` to become a member. */
+  inviteCode: string;
+  /** Every member of this household, including the caller. */
+  members: HouseMemberView[];
 }