diff --git a/cdk/lib/__snapshots__/prism.test.ts.snap b/cdk/lib/__snapshots__/prism.test.ts.snap
index 1a870e97..0f17da1c 100644
--- a/cdk/lib/__snapshots__/prism.test.ts.snap
+++ b/cdk/lib/__snapshots__/prism.test.ts.snap
@@ -79,7 +79,7 @@ exports[`The PrismEc2App stack matches the snapshot 1`] = `
   "Resources": {
     "AutoScalingGroupPrismASG36691601": {
       "Properties": {
-        "HealthCheckGracePeriod": 500,
+        "HealthCheckGracePeriod": 900,
         "HealthCheckType": "ELB",
         "LaunchTemplate": {
           "LaunchTemplateId": {
diff --git a/cdk/lib/prism.ts b/cdk/lib/prism.ts
index 32310671..75f969d7 100644
--- a/cdk/lib/prism.ts
+++ b/cdk/lib/prism.ts
@@ -109,6 +109,6 @@ export class Prism extends GuStack {
 		// Similarly the pattern does not offer support for extending the default ASG grace period via props
 		const cfnAsg = pattern.autoScalingGroup.node
 			.defaultChild as CfnAutoScalingGroup;
-		cfnAsg.healthCheckGracePeriod = 500;
+		cfnAsg.healthCheckGracePeriod = Duration.minutes(15).toSeconds();
 	}
 }