diff --git a/CHANGES.md b/CHANGES.md
index 159ceee7..8a9d7e6e 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -4,8 +4,22 @@ Notable changes between versions.
 
 ## Latest
 
+* Add Terraform v0.15.x support ([#974](https://github.com/poseidon/typhoon/pull/974))
+  * Continue to support Terraform v0.13.x and v0.14.4+
 * Update Cilium from v1.9.5 to [v1.9.6](https://github.com/cilium/cilium/releases/tag/v1.9.6)
 
+### AWS
+
+* Reduce the default `disk_size` from 40GB to 30GB ([#983](https://github.com/poseidon/typhoon/pull/983))
+
+### Azure
+
+* Reduce the default `disk_size` from 40GB to 30GB ([#983](https://github.com/poseidon/typhoon/pull/983))
+
+### Google Cloud
+
+* Reduce the default `disk_size` from 40GB to 30GB ([#983](https://github.com/poseidon/typhoon/pull/983))
+
 ### Addons
 
 * Update kube-state-metrics from v2.0.0-rc.1 to [v2.0.0](https://github.com/kubernetes/kube-state-metrics/releases/tag/v2.0.0)
diff --git a/aws/fedora-coreos/kubernetes/variables.tf b/aws/fedora-coreos/kubernetes/variables.tf
index 95a09e26..de7d7acd 100644
--- a/aws/fedora-coreos/kubernetes/variables.tf
+++ b/aws/fedora-coreos/kubernetes/variables.tf
@@ -55,7 +55,7 @@ variable "os_stream" {
 variable "disk_size" {
   type        = number
   description = "Size of the EBS volume in GB"
-  default     = 40
+  default     = 30
 }
 
 variable "disk_type" {
diff --git a/aws/fedora-coreos/kubernetes/workers/variables.tf b/aws/fedora-coreos/kubernetes/workers/variables.tf
index aadb4ade..034ad350 100644
--- a/aws/fedora-coreos/kubernetes/workers/variables.tf
+++ b/aws/fedora-coreos/kubernetes/workers/variables.tf
@@ -48,7 +48,7 @@ variable "os_stream" {
 variable "disk_size" {
   type        = number
   description = "Size of the EBS volume in GB"
-  default     = 40
+  default     = 30
 }
 
 variable "disk_type" {
diff --git a/aws/flatcar-linux/kubernetes/variables.tf b/aws/flatcar-linux/kubernetes/variables.tf
index d38f8aa9..e0a71504 100644
--- a/aws/flatcar-linux/kubernetes/variables.tf
+++ b/aws/flatcar-linux/kubernetes/variables.tf
@@ -55,7 +55,7 @@ variable "os_image" {
 variable "disk_size" {
   type        = number
   description = "Size of the EBS volume in GB"
-  default     = 40
+  default     = 30
 }
 
 variable "disk_type" {
diff --git a/aws/flatcar-linux/kubernetes/workers/variables.tf b/aws/flatcar-linux/kubernetes/workers/variables.tf
index a4dbab75..abb8c2b5 100644
--- a/aws/flatcar-linux/kubernetes/workers/variables.tf
+++ b/aws/flatcar-linux/kubernetes/workers/variables.tf
@@ -48,7 +48,7 @@ variable "os_image" {
 variable "disk_size" {
   type        = number
   description = "Size of the EBS volume in GB"
-  default     = 40
+  default     = 30
 }
 
 variable "disk_type" {
diff --git a/azure/fedora-coreos/kubernetes/variables.tf b/azure/fedora-coreos/kubernetes/variables.tf
index d5191047..de04d6c3 100644
--- a/azure/fedora-coreos/kubernetes/variables.tf
+++ b/azure/fedora-coreos/kubernetes/variables.tf
@@ -54,7 +54,7 @@ variable "os_image" {
 variable "disk_size" {
   type        = number
   description = "Size of the disk in GB"
-  default     = 40
+  default     = 30
 }
 
 variable "worker_priority" {
diff --git a/azure/flatcar-linux/kubernetes/variables.tf b/azure/flatcar-linux/kubernetes/variables.tf
index 07694d0f..6e0e3714 100644
--- a/azure/flatcar-linux/kubernetes/variables.tf
+++ b/azure/flatcar-linux/kubernetes/variables.tf
@@ -60,7 +60,7 @@ variable "os_image" {
 variable "disk_size" {
   type        = number
   description = "Size of the disk in GB"
-  default     = 40
+  default     = 30
 }
 
 variable "worker_priority" {
diff --git a/docs/fedora-coreos/aws.md b/docs/fedora-coreos/aws.md
index 95dc563f..7ff78185 100644
--- a/docs/fedora-coreos/aws.md
+++ b/docs/fedora-coreos/aws.md
@@ -211,7 +211,7 @@ Reference the DNS zone id with `aws_route53_zone.zone-for-clusters.zone_id`.
 | controller_type | EC2 instance type for controllers | "t3.small" | See below |
 | worker_type | EC2 instance type for workers | "t3.small" | See below |
 | os_stream | Fedora CoreOS stream for compute instances | "stable" | "testing", "next" |
-| disk_size | Size of the EBS volume in GB | 40 | 100 |
+| disk_size | Size of the EBS volume in GB | 30 | 100 |
 | disk_type | Type of the EBS volume | "gp2" | standard, gp2, io1 |
 | disk_iops | IOPS of the EBS volume | 0 (i.e. auto) | 400 |
 | worker_target_groups | Target group ARNs to which worker instances should be added | [] | [aws_lb_target_group.app.id] |
diff --git a/docs/fedora-coreos/azure.md b/docs/fedora-coreos/azure.md
index 15dfeb55..8401fb14 100644
--- a/docs/fedora-coreos/azure.md
+++ b/docs/fedora-coreos/azure.md
@@ -241,7 +241,7 @@ Reference the DNS zone with `azurerm_dns_zone.clusters.name` and its resource gr
 | worker_count | Number of workers | 1 | 3 |
 | controller_type | Machine type for controllers | "Standard_B2s" | See below |
 | worker_type | Machine type for workers | "Standard_DS1_v2" | See below |
-| disk_size | Size of the disk in GB | 40 | 100 |
+| disk_size | Size of the disk in GB | 30 | 100 |
 | worker_priority | Set priority to Spot to use reduced cost surplus capacity, with the tradeoff that instances can be deallocated at any time | Regular | Spot |
 | controller_snippets | Controller Fedora CoreOS Config snippets | [] | [example](/advanced/customization/#usage) |
 | worker_snippets | Worker Fedora CoreOS Config snippets | [] | [example](/advanced/customization/#usage) |
diff --git a/docs/fedora-coreos/google-cloud.md b/docs/fedora-coreos/google-cloud.md
index 7fd62f7a..c4548730 100644
--- a/docs/fedora-coreos/google-cloud.md
+++ b/docs/fedora-coreos/google-cloud.md
@@ -216,7 +216,7 @@ resource "google_dns_managed_zone" "zone-for-clusters" {
 | controller_type | Machine type for controllers | "n1-standard-1" | See below |
 | worker_type | Machine type for workers | "n1-standard-1" | See below |
 | os_stream | Fedora CoreOS stream for compute instances | "stable" | "stable", "testing", "next" |
-| disk_size | Size of the disk in GB | 40 | 100 |
+| disk_size | Size of the disk in GB | 30 | 100 |
 | worker_preemptible | If enabled, Compute Engine will terminate workers randomly within 24 hours | false | true |
 | controller_snippets | Controller Fedora CoreOS Config snippets | [] | [examples](/advanced/customization/) |
 | worker_snippets | Worker Fedora CoreOS Config snippets | [] | [examples](/advanced/customization/) |
diff --git a/docs/flatcar-linux/aws.md b/docs/flatcar-linux/aws.md
index 785848d6..49d459e3 100644
--- a/docs/flatcar-linux/aws.md
+++ b/docs/flatcar-linux/aws.md
@@ -211,7 +211,7 @@ Reference the DNS zone id with `aws_route53_zone.zone-for-clusters.zone_id`.
 | controller_type | EC2 instance type for controllers | "t3.small" | See below |
 | worker_type | EC2 instance type for workers | "t3.small" | See below |
 | os_image | AMI channel for a Container Linux derivative | "flatcar-stable" | flatcar-stable, flatcar-beta, flatcar-alpha |
-| disk_size | Size of the EBS volume in GB | 40 | 100 |
+| disk_size | Size of the EBS volume in GB | 30 | 100 |
 | disk_type | Type of the EBS volume | "gp2" | standard, gp2, io1 |
 | disk_iops | IOPS of the EBS volume | 0 (i.e. auto) | 400 |
 | worker_target_groups | Target group ARNs to which worker instances should be added | [] | [aws_lb_target_group.app.id] |
diff --git a/docs/flatcar-linux/azure.md b/docs/flatcar-linux/azure.md
index 6a18726d..749247dc 100644
--- a/docs/flatcar-linux/azure.md
+++ b/docs/flatcar-linux/azure.md
@@ -229,7 +229,7 @@ Reference the DNS zone with `azurerm_dns_zone.clusters.name` and its resource gr
 | controller_type | Machine type for controllers | "Standard_B2s" | See below |
 | worker_type | Machine type for workers | "Standard_DS1_v2" | See below |
 | os_image | Channel for a Container Linux derivative | "flatcar-stable" | flatcar-stable, flatcar-beta, flatcar-alpha |
-| disk_size | Size of the disk in GB | 40 | 100 |
+| disk_size | Size of the disk in GB | 30 | 100 |
 | worker_priority | Set priority to Spot to use reduced cost surplus capacity, with the tradeoff that instances can be deallocated at any time | Regular | Spot |
 | controller_snippets | Controller Container Linux Config snippets | [] | [example](/advanced/customization/#usage) |
 | worker_snippets | Worker Container Linux Config snippets | [] | [example](/advanced/customization/#usage) |
diff --git a/docs/flatcar-linux/google-cloud.md b/docs/flatcar-linux/google-cloud.md
index 78f765ef..875cfb6e 100644
--- a/docs/flatcar-linux/google-cloud.md
+++ b/docs/flatcar-linux/google-cloud.md
@@ -236,7 +236,7 @@ resource "google_dns_managed_zone" "zone-for-clusters" {
 | worker_count | Number of workers | 1 | 3 |
 | controller_type | Machine type for controllers | "n1-standard-1" | See below |
 | worker_type | Machine type for workers | "n1-standard-1" | See below |
-| disk_size | Size of the disk in GB | 40 | 100 |
+| disk_size | Size of the disk in GB | 30 | 100 |
 | worker_preemptible | If enabled, Compute Engine will terminate workers randomly within 24 hours | false | true |
 | controller_snippets | Controller Container Linux Config snippets | [] | [example](/advanced/customization/) |
 | worker_snippets | Worker Container Linux Config snippets | [] | [example](/advanced/customization/) |
diff --git a/google-cloud/fedora-coreos/kubernetes/variables.tf b/google-cloud/fedora-coreos/kubernetes/variables.tf
index c3d2d700..e0e9c3a4 100644
--- a/google-cloud/fedora-coreos/kubernetes/variables.tf
+++ b/google-cloud/fedora-coreos/kubernetes/variables.tf
@@ -60,7 +60,7 @@ variable "os_stream" {
 variable "disk_size" {
   type        = number
   description = "Size of the disk in GB"
-  default     = 40
+  default     = 30
 }
 
 variable "worker_preemptible" {
diff --git a/google-cloud/fedora-coreos/kubernetes/workers/variables.tf b/google-cloud/fedora-coreos/kubernetes/workers/variables.tf
index 7d19f3a1..ae30443f 100644
--- a/google-cloud/fedora-coreos/kubernetes/workers/variables.tf
+++ b/google-cloud/fedora-coreos/kubernetes/workers/variables.tf
@@ -48,7 +48,7 @@ variable "os_stream" {
 variable "disk_size" {
   type        = number
   description = "Size of the disk in GB"
-  default     = 40
+  default     = 30
 }
 
 variable "preemptible" {
diff --git a/google-cloud/flatcar-linux/kubernetes/variables.tf b/google-cloud/flatcar-linux/kubernetes/variables.tf
index e23a304b..91af7df7 100644
--- a/google-cloud/flatcar-linux/kubernetes/variables.tf
+++ b/google-cloud/flatcar-linux/kubernetes/variables.tf
@@ -54,7 +54,7 @@ variable "os_image" {
 variable "disk_size" {
   type        = number
   description = "Size of the disk in GB"
-  default     = 40
+  default     = 30
 }
 
 variable "worker_preemptible" {
diff --git a/google-cloud/flatcar-linux/kubernetes/workers/variables.tf b/google-cloud/flatcar-linux/kubernetes/workers/variables.tf
index b430c6c8..36e2e910 100644
--- a/google-cloud/flatcar-linux/kubernetes/workers/variables.tf
+++ b/google-cloud/flatcar-linux/kubernetes/workers/variables.tf
@@ -42,7 +42,7 @@ variable "os_image" {
 variable "disk_size" {
   type        = number
   description = "Size of the disk in GB"
-  default     = 40
+  default     = 30
 }
 
 variable "preemptible" {