diff --git a/apps/ui/templates/room.html b/apps/ui/templates/room.html
new file mode 100644
index 0000000..2db761c
--- /dev/null
+++ b/apps/ui/templates/room.html
@@ -0,0 +1,484 @@
+<!DOCTYPE html>
+<html lang="de">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Raum - Home Automation</title>
+    <style>
+        * {
+            margin: 0;
+            padding: 0;
+            box-sizing: border-box;
+        }
+
+        body {
+            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
+            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
+            min-height: 100vh;
+            padding: 20px;
+        }
+
+        .container {
+            max-width: 1200px;
+            margin: 0 auto;
+        }
+
+        .header {
+            background: rgba(255, 255, 255, 0.95);
+            border-radius: 12px;
+            padding: 20px;
+            margin-bottom: 20px;
+            box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
+        }
+
+        .back-button {
+            background: none;
+            border: none;
+            color: #667eea;
+            font-size: 16px;
+            cursor: pointer;
+            padding: 8px 0;
+            margin-bottom: 12px;
+            display: inline-block;
+            text-decoration: none;
+        }
+
+        .back-button:hover {
+            text-decoration: underline;
+        }
+
+        h1 {
+            color: #333;
+            font-size: 28px;
+            margin-bottom: 8px;
+        }
+
+        .room-info {
+            color: #666;
+            font-size: 14px;
+        }
+
+        .devices-grid {
+            display: grid;
+            grid-template-columns: repeat(2, 1fr);
+            gap: 16px;
+        }
+
+        @media (min-width: 600px) {
+            .devices-grid {
+                grid-template-columns: repeat(3, 1fr);
+            }
+        }
+
+        @media (min-width: 900px) {
+            .devices-grid {
+                grid-template-columns: repeat(4, 1fr);
+            }
+        }
+
+        .device-card {
+            background: rgba(255, 255, 255, 0.95);
+            border-radius: 12px;
+            padding: 16px;
+            cursor: pointer;
+            transition: all 0.2s ease;
+            box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
+            min-height: 120px;
+            display: flex;
+            flex-direction: column;
+            text-decoration: none;
+            color: inherit;
+        }
+
+        .device-card:hover {
+            transform: translateY(-4px);
+            box-shadow: 0 4px 16px rgba(0, 0, 0, 0.2);
+        }
+
+        .device-card:active {
+            transform: translateY(-2px);
+        }
+
+        .device-header {
+            display: flex;
+            align-items: center;
+            gap: 12px;
+            margin-bottom: 12px;
+        }
+
+        .device-icon {
+            font-size: 24px;
+        }
+
+        .device-title {
+            font-size: 16px;
+            font-weight: 600;
+            color: #333;
+            flex: 1;
+            line-height: 1.3;
+        }
+
+        .device-state {
+            margin-top: auto;
+        }
+
+        .state-primary {
+            font-size: 20px;
+            font-weight: 600;
+            color: #667eea;
+            margin-bottom: 4px;
+        }
+
+        .state-secondary {
+            font-size: 14px;
+            color: #666;
+        }
+
+        .state-badge {
+            display: inline-block;
+            padding: 4px 12px;
+            border-radius: 12px;
+            font-size: 13px;
+            font-weight: 500;
+        }
+
+        .state-badge.on {
+            background: #34c759;
+            color: white;
+        }
+
+        .state-badge.off {
+            background: #e0e0e0;
+            color: #666;
+        }
+
+        .state-badge.open {
+            background: #ff9500;
+            color: white;
+        }
+
+        .state-badge.closed {
+            background: #34c759;
+            color: white;
+        }
+
+        .loading {
+            text-align: center;
+            color: white;
+            font-size: 18px;
+            padding: 40px;
+        }
+
+        .error {
+            background: rgba(255, 59, 48, 0.9);
+            color: white;
+            padding: 16px;
+            border-radius: 8px;
+            text-align: center;
+            margin-bottom: 20px;
+        }
+
+        .no-devices {
+            background: rgba(255, 255, 255, 0.95);
+            border-radius: 12px;
+            padding: 40px;
+            text-align: center;
+            color: #666;
+        }
+    </style>
+</head>
+<body>
+    <div class="container">
+        <div class="header">
+            <a href="/rooms" class="back-button">← Zurück zu Räumen</a>
+            <h1 id="room-name">Raum wird geladen...</h1>
+            <div class="room-info" id="room-info"></div>
+        </div>
+        
+        <div id="error-container"></div>
+        <div id="loading" class="loading">Lade Geräte...</div>
+        <div id="devices-grid" class="devices-grid" style="display: none;"></div>
+        <div id="no-devices" class="no-devices" style="display: none;">
+            Keine Geräte in diesem Raum gefunden.
+        </div>
+    </div>
+
+    <script>
+        // API configuration from backend
+        window.API_BASE = '{{ api_base }}';
+        
+        // Helper function to construct API URLs
+        function api(url) {
+            return `${window.API_BASE}${url}`;
+        }
+
+        // Get room name from URL
+        const pathParts = window.location.pathname.split('/');
+        const roomName = decodeURIComponent(pathParts[pathParts.length - 1]);
+
+        // Device type to icon mapping
+        const deviceIcons = {
+            'light': '💡',
+            'thermostat': '🌡️',
+            'contact': '🚪',
+            'temp_humidity_sensor': '🌡️',
+            'relay': '🔌',
+            'outlet': '🔌',
+            'cover': '🪟'
+        };
+
+        // Device states
+        const deviceStates = {};
+
+        // SSE connection
+        let eventSource = null;
+
+        async function loadRoom() {
+            const loading = document.getElementById('loading');
+            const grid = document.getElementById('devices-grid');
+            const noDevices = document.getElementById('no-devices');
+            const errorContainer = document.getElementById('error-container');
+            const roomNameEl = document.getElementById('room-name');
+            const roomInfoEl = document.getElementById('room-info');
+
+            try {
+                // Load layout
+                const layoutResponse = await fetch(api('/layout'));
+                if (!layoutResponse.ok) {
+                    throw new Error(`Layout API error: ${layoutResponse.status}`);
+                }
+                const layoutData = await layoutResponse.json();
+
+                // Find the room
+                const room = layoutData.rooms.find(r => r.name === roomName);
+                if (!room) {
+                    throw new Error(`Raum "${roomName}" nicht gefunden`);
+                }
+
+                // Update header
+                roomNameEl.textContent = room.name;
+                roomInfoEl.textContent = `${room.devices.length} Gerät${room.devices.length !== 1 ? 'e' : ''}`;
+
+                // Load devices
+                const devicesResponse = await fetch(api('/devices'));
+                if (!devicesResponse.ok) {
+                    throw new Error(`Devices API error: ${devicesResponse.status}`);
+                }
+                const devicesData = await devicesResponse.json();
+
+                // Create device lookup
+                const deviceMap = {};
+                devicesData.forEach(device => {
+                    deviceMap[device.device_id] = device;
+                });
+
+                // Filter devices for this room
+                const roomDevices = room.devices
+                    .map(deviceId => deviceMap[deviceId])
+                    .filter(device => device != null);
+
+                loading.style.display = 'none';
+
+                if (roomDevices.length === 0) {
+                    noDevices.style.display = 'block';
+                    return;
+                }
+
+                // Load initial states
+                await loadDeviceStates(roomDevices.map(d => d.device_id));
+
+                // Render devices
+                grid.style.display = 'grid';
+                roomDevices.forEach(device => {
+                    const card = createDeviceCard(device);
+                    grid.appendChild(card);
+                });
+
+                // Start SSE for live updates
+                connectRealtime();
+
+            } catch (error) {
+                console.error('Error loading room:', error);
+                loading.style.display = 'none';
+                errorContainer.innerHTML = `
+                    <div class="error">
+                        ⚠️ Fehler beim Laden: ${error.message}
+                    </div>
+                `;
+            }
+        }
+
+        async function loadDeviceStates(deviceIds) {
+            try {
+                // Load states for all devices
+                const statePromises = deviceIds.map(async deviceId => {
+                    try {
+                        const response = await fetch(api(`/devices/${deviceId}/state`));
+                        if (response.ok) {
+                            const state = await response.json();
+                            deviceStates[deviceId] = state;
+                        }
+                    } catch (e) {
+                        console.warn(`Failed to load state for ${deviceId}:`, e);
+                    }
+                });
+                await Promise.all(statePromises);
+            } catch (error) {
+                console.error('Error loading device states:', error);
+            }
+        }
+
+        function createDeviceCard(device) {
+            const card = document.createElement('a');
+            card.className = 'device-card';
+            card.href = `/device/${device.device_id}`;
+            card.dataset.deviceId = device.device_id;
+
+            const header = document.createElement('div');
+            header.className = 'device-header';
+
+            const icon = document.createElement('div');
+            icon.className = 'device-icon';
+            icon.textContent = deviceIcons[device.type] || '📱';
+
+            const title = document.createElement('div');
+            title.className = 'device-title';
+            title.textContent = device.name;
+
+            header.appendChild(icon);
+            header.appendChild(title);
+
+            const stateDiv = document.createElement('div');
+            stateDiv.className = 'device-state';
+            updateDeviceCardState(stateDiv, device);
+
+            card.appendChild(header);
+            card.appendChild(stateDiv);
+
+            return card;
+        }
+
+        function updateDeviceCardState(stateDiv, device) {
+            const state = deviceStates[device.device_id];
+            if (!state) {
+                stateDiv.innerHTML = '<div class="state-secondary">Status unbekannt</div>';
+                return;
+            }
+
+            let html = '';
+
+            switch (device.type) {
+                case 'light':
+                    if (state.power) {
+                        const powerState = state.power === 'on';
+                        html = `<span class="state-badge ${powerState ? 'on' : 'off'}">${powerState ? 'An' : 'Aus'}</span>`;
+                        if (powerState && state.brightness != null) {
+                            html += `<div class="state-secondary">${state.brightness}% Helligkeit</div>`;
+                        }
+                    }
+                    break;
+
+                case 'thermostat':
+                    if (state.current_temp != null) {
+                        html = `<div class="state-primary">${state.current_temp.toFixed(1)}°C</div>`;
+                        if (state.target_temp != null) {
+                            html += `<div class="state-secondary">Ziel: ${state.target_temp}°C</div>`;
+                        }
+                    }
+                    break;
+
+                case 'contact':
+                    if (state.contact != null) {
+                        const isOpen = state.contact === 'open';
+                        html = `<span class="state-badge ${isOpen ? 'open' : 'closed'}">${isOpen ? 'Offen' : 'Geschlossen'}</span>`;
+                    }
+                    break;
+
+                case 'temp_humidity_sensor':
+                    if (state.temperature != null) {
+                        html = `<div class="state-primary">${state.temperature.toFixed(1)}°C</div>`;
+                        if (state.humidity != null) {
+                            html += `<div class="state-secondary">${state.humidity}% Luftfeuchte</div>`;
+                        }
+                    }
+                    break;
+
+                case 'relay':
+                case 'outlet':
+                    if (state.power) {
+                        const powerState = state.power === 'on';
+                        html = `<span class="state-badge ${powerState ? 'on' : 'off'}">${powerState ? 'An' : 'Aus'}</span>`;
+                    }
+                    break;
+
+                case 'cover':
+                    if (state.position != null) {
+                        html = `<div class="state-primary">${state.position}%</div>`;
+                        html += `<div class="state-secondary">Position</div>`;
+                    }
+                    break;
+
+                default:
+                    html = '<div class="state-secondary">Kein Status</div>';
+            }
+
+            stateDiv.innerHTML = html;
+        }
+
+        function connectRealtime() {
+            try {
+                eventSource = new EventSource(api('/realtime'));
+
+                eventSource.onmessage = (event) => {
+                    try {
+                        const data = JSON.parse(event.data);
+                        
+                        // Update device state
+                        if (data.device_id && data.payload) {
+                            deviceStates[data.device_id] = data.payload;
+                            
+                            // Update card if visible
+                            const card = document.querySelector(`[data-device-id="${data.device_id}"]`);
+                            if (card) {
+                                const stateDiv = card.querySelector('.device-state');
+                                const devicesResponse = fetch(api('/devices')).then(r => r.json()).then(devices => {
+                                    const device = devices.find(d => d.device_id === data.device_id);
+                                    if (device) {
+                                        updateDeviceCardState(stateDiv, device);
+                                    }
+                                });
+                            }
+                        }
+                    } catch (e) {
+                        console.warn('Failed to parse SSE event:', e);
+                    }
+                };
+
+                eventSource.onerror = (error) => {
+                    console.error('SSE connection error:', error);
+                    // Auto-reconnect after 5 seconds
+                    setTimeout(() => {
+                        if (eventSource) {
+                            eventSource.close();
+                            connectRealtime();
+                        }
+                    }, 5000);
+                };
+
+            } catch (error) {
+                console.error('Failed to connect to realtime events:', error);
+            }
+        }
+
+        // Cleanup on page unload
+        window.addEventListener('beforeunload', () => {
+            if (eventSource) {
+                eventSource.close();
+            }
+        });
+
+        // Load room on page load
+        document.addEventListener('DOMContentLoaded', loadRoom);
+    </script>
+</body>
+</html>
