diff --git a/.gitignore b/.gitignore
index a3d7314..4058a64 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,5 @@
 *.tfstate*
 .terraform/
 spec/reports/*
+
+.idea/
\ No newline at end of file
diff --git a/group/asg/main.tf b/group/asg/main.tf
index 50979db..3c2ec2e 100644
--- a/group/asg/main.tf
+++ b/group/asg/main.tf
@@ -5,13 +5,13 @@ locals {
   default_asg_tags = [
     {
       key                 = "application"
-      value               = "${var.stack_item_fullname}"
+      value               = var.stack_item_fullname
       propagate_at_launch = true
     },
     {
       key                 = "Name"
-      value               = "${length(var.asg_name_override) > 0 ? var.asg_name_override : var.stack_item_label}"
-      propagate_at_launch = "${var.propagate_name_at_launch}"
+      value               = length(var.asg_name_override) > 0 ? var.asg_name_override : var.stack_item_label
+      propagate_at_launch = var.propagate_name_at_launch
     },
     {
       key                 = "managed_by"
@@ -22,54 +22,55 @@ locals {
 }
 
 resource "aws_autoscaling_group" "asg" {
-  count = "${length(var.min_elb_capacity) > 0 || length(var.wait_for_elb_capacity) > 0 ? 0 : 1}"
+  count = length(var.min_elb_capacity) > 0 || length(var.wait_for_elb_capacity) > 0 ? 0 : 1
 
-  default_cooldown          = "${length(var.default_cooldown) > 0 ? var.default_cooldown : "300"}"
-  desired_capacity          = "${length(var.desired_capacity) > 0 ? var.desired_capacity : var.min_size}"
-  enabled_metrics           = ["${compact(var.enabled_metrics)}"]
-  force_delete              = "${var.force_delete}"
-  health_check_grace_period = "${length(var.hc_grace_period) > 0 ? var.hc_grace_period : "300"}"
+  default_cooldown          = length(var.default_cooldown) > 0 ? var.default_cooldown : "300"
+  desired_capacity          = length(var.desired_capacity) > 0 ? var.desired_capacity : var.min_size
+  enabled_metrics           = compact(var.enabled_metrics)
+  force_delete              = var.force_delete
+  health_check_grace_period = length(var.hc_grace_period) > 0 ? var.hc_grace_period : "300"
   health_check_type         = "EC2"
-  launch_configuration      = "${var.lc_id}"
-  max_size                  = "${var.max_size}"
-  metrics_granularity       = "${var.metrics_granularity}"
-  min_size                  = "${var.min_size}"
-  name                      = "${length(var.asg_name_override) > 0 ? var.asg_name_override : var.stack_item_label}"
-  placement_group           = "${var.placement_group}"
-  protect_from_scale_in     = "${var.protect_from_scale_in}"
-  suspended_processes       = ["${compact(var.suspended_processes)}"]
-  target_group_arns         = ["${compact(var.target_group_arns)}"]
-  termination_policies      = ["${compact(var.termination_policies)}"]
-  vpc_zone_identifier       = ["${compact(var.subnets)}"]
-  wait_for_capacity_timeout = "${length(var.wait_for_capacity_timeout) > 0 ? var.wait_for_capacity_timeout : "10m"}"
+  launch_configuration      = var.lc_id
+  max_size                  = var.max_size
+  metrics_granularity       = var.metrics_granularity
+  min_size                  = var.min_size
+  name                      = length(var.asg_name_override) > 0 ? var.asg_name_override : var.stack_item_label
+  placement_group           = var.placement_group
+  protect_from_scale_in     = var.protect_from_scale_in
+  suspended_processes       = compact(var.suspended_processes)
+  target_group_arns         = compact(var.target_group_arns)
+  termination_policies      = compact(var.termination_policies)
+  vpc_zone_identifier       = compact(var.subnets)
+  wait_for_capacity_timeout = length(var.wait_for_capacity_timeout) > 0 ? var.wait_for_capacity_timeout : "10m"
 
-  tags = "${concat(local.default_asg_tags, var.additional_asg_tags)}"
+  tags = concat(local.default_asg_tags, var.additional_asg_tags)
 }
 
 resource "aws_autoscaling_group" "asg_elb" {
-  count = "${length(var.min_elb_capacity) > 0 || length(var.wait_for_elb_capacity) > 0 ? 1 : 0}"
+  count = length(var.min_elb_capacity) > 0 || length(var.wait_for_elb_capacity) > 0 ? 1 : 0
 
-  default_cooldown          = "${length(var.default_cooldown) > 0 ? var.default_cooldown : "300"}"
-  desired_capacity          = "${length(var.desired_capacity) > 0 ? var.desired_capacity : var.min_size}"
-  enabled_metrics           = ["${compact(var.enabled_metrics)}"]
-  force_delete              = "${var.force_delete}"
-  health_check_grace_period = "${length(var.hc_grace_period) > 0 ? var.hc_grace_period : "300"}"
-  health_check_type         = "${length(var.hc_check_type) > 0 ? var.hc_check_type : "ELB"}"
-  launch_configuration      = "${var.lc_id}"
-  load_balancers            = ["${compact(var.load_balancers)}"]
-  max_size                  = "${var.max_size}"
-  metrics_granularity       = "${var.metrics_granularity}"
-  min_elb_capacity          = "${length(var.min_elb_capacity) > 0 ? var.min_elb_capacity : "0"}"
-  min_size                  = "${var.min_size}"
-  name                      = "${length(var.asg_name_override) > 0 ? var.asg_name_override : var.stack_item_label}"
-  placement_group           = "${var.placement_group}"
-  protect_from_scale_in     = "${var.protect_from_scale_in}"
-  suspended_processes       = ["${compact(var.suspended_processes)}"]
-  target_group_arns         = ["${compact(var.target_group_arns)}"]
-  termination_policies      = ["${compact(var.termination_policies)}"]
-  vpc_zone_identifier       = ["${compact(var.subnets)}"]
-  wait_for_capacity_timeout = "${length(var.wait_for_capacity_timeout) > 0 ? var.wait_for_capacity_timeout : "10m"}"
-  wait_for_elb_capacity     = "${length(var.wait_for_elb_capacity) > 0 ? var.wait_for_elb_capacity : "0"}"
+  default_cooldown          = length(var.default_cooldown) > 0 ? var.default_cooldown : "300"
+  desired_capacity          = length(var.desired_capacity) > 0 ? var.desired_capacity : var.min_size
+  enabled_metrics           = compact(var.enabled_metrics)
+  force_delete              = var.force_delete
+  health_check_grace_period = length(var.hc_grace_period) > 0 ? var.hc_grace_period : "300"
+  health_check_type         = length(var.hc_check_type) > 0 ? var.hc_check_type : "ELB"
+  launch_configuration      = var.lc_id
+  load_balancers            = compact(var.load_balancers)
+  max_size                  = var.max_size
+  metrics_granularity       = var.metrics_granularity
+  min_elb_capacity          = length(var.min_elb_capacity) > 0 ? var.min_elb_capacity : "0"
+  min_size                  = var.min_size
+  name                      = length(var.asg_name_override) > 0 ? var.asg_name_override : var.stack_item_label
+  placement_group           = var.placement_group
+  protect_from_scale_in     = var.protect_from_scale_in
+  suspended_processes       = compact(var.suspended_processes)
+  target_group_arns         = compact(var.target_group_arns)
+  termination_policies      = compact(var.termination_policies)
+  vpc_zone_identifier       = compact(var.subnets)
+  wait_for_capacity_timeout = length(var.wait_for_capacity_timeout) > 0 ? var.wait_for_capacity_timeout : "10m"
+  wait_for_elb_capacity     = length(var.wait_for_elb_capacity) > 0 ? var.wait_for_elb_capacity : "0"
 
-  tags = "${concat(local.default_asg_tags, var.additional_asg_tags)}"
+  tags = concat(local.default_asg_tags, var.additional_asg_tags)
 }
+
diff --git a/group/asg/outputs.tf b/group/asg/outputs.tf
index 9a7eef7..35d1c18 100644
--- a/group/asg/outputs.tf
+++ b/group/asg/outputs.tf
@@ -1,9 +1,16 @@
 # Outputs
 
 output "asg_id" {
-  value = "${coalesce(join(",",aws_autoscaling_group.asg.*.id),join(",",aws_autoscaling_group.asg_elb.*.id))}"
+  value = coalesce(
+    join(",", aws_autoscaling_group.asg.*.id),
+    join(",", aws_autoscaling_group.asg_elb.*.id),
+  )
 }
 
 output "asg_name" {
-  value = "${coalesce(join(",",aws_autoscaling_group.asg.*.name),join(",",aws_autoscaling_group.asg_elb.*.name))}"
+  value = coalesce(
+    join(",", aws_autoscaling_group.asg.*.name),
+    join(",", aws_autoscaling_group.asg_elb.*.name),
+  )
 }
+
diff --git a/group/asg/variables.tf b/group/asg/variables.tf
index 0cf21c2..2628e25 100644
--- a/group/asg/variables.tf
+++ b/group/asg/variables.tf
@@ -2,109 +2,110 @@
 
 ## Resource tags
 variable "stack_item_fullname" {
-  type = "string"
+  type = string
 }
 
 variable "stack_item_label" {
-  type = "string"
+  type = string
 }
 
 variable "additional_asg_tags" {
-  type    = "list"
+  type    = list(string)
   default = []
 }
 
 ## Allow override of resource naming
 variable "asg_name_override" {
-  type = "string"
+  type = string
 }
 
 variable "propagate_name_at_launch" {
-  type    = "string"
+  type    = string
   default = "true"
 }
 
 ## VPC parameters
 variable "subnets" {
-  type = "list"
+  type = list(string)
 }
 
 ## LC parameters
 variable "lc_id" {
-  type = "string"
+  type = string
 }
 
 ## ASG parameters
 
 variable "default_cooldown" {
-  type = "string"
+  type = string
 }
 
 variable "desired_capacity" {
-  type = "string"
+  type = string
 }
 
 variable "enabled_metrics" {
-  type = "list"
+  type = list(string)
 }
 
 variable "force_delete" {
-  type = "string"
+  type = string
 }
 
 variable "hc_check_type" {
-  type = "string"
+  type = string
 }
 
 variable "hc_grace_period" {
-  type = "string"
+  type = string
 }
 
 variable "max_size" {
-  type = "string"
+  type = string
 }
 
 variable "metrics_granularity" {
-  type = "string"
+  type = string
 }
 
 variable "min_size" {
-  type = "string"
+  type = string
 }
 
 variable "placement_group" {
-  type = "string"
+  type = string
 }
 
 variable "protect_from_scale_in" {
-  type = "string"
+  type = bool
 }
 
 variable "suspended_processes" {
-  type = "list"
+  type = list(string)
 }
 
 variable "termination_policies" {
-  type = "list"
+  type = list(string)
 }
 
 variable "wait_for_capacity_timeout" {
-  type = "string"
+  type = string
 }
 
 ## ELB parameters
 variable "load_balancers" {
-  type = "list"
+  type = list(string)
 }
 
 variable "min_elb_capacity" {
-  type = "string"
+  type = string
 }
 
 variable "target_group_arns" {
-  type = "list"
+  type = list(string)
 }
 
 variable "wait_for_elb_capacity" {
-  type = "string"
+  type = string
 }
+
diff --git a/group/asg/versions.tf b/group/asg/versions.tf
new file mode 100644
index 0000000..ac97c6a
--- /dev/null
+++ b/group/asg/versions.tf
@@ -0,0 +1,4 @@
+
+terraform {
+  required_version = ">= 0.12"
+}
diff --git a/group/lc/main.tf b/group/lc/main.tf
index d45ac9a..8a26c4f 100644
--- a/group/lc/main.tf
+++ b/group/lc/main.tf
@@ -3,13 +3,13 @@
 ## Creates security group
 resource "aws_security_group" "sg_asg" {
   description = "${var.stack_item_fullname} security group"
-  name_prefix = "${length(var.lc_sg_name_prefix_override) > 0 ? format("%s-", var.lc_sg_name_prefix_override) : format("%s-asg-", var.stack_item_label)}"
-  vpc_id      = "${var.vpc_id}"
+  name_prefix = length(var.lc_sg_name_prefix_override) > 0 ? format("%s-", var.lc_sg_name_prefix_override) : format("%s-asg-", var.stack_item_label)
+  vpc_id      = var.vpc_id
 
-  tags {
-    application = "${var.stack_item_fullname}"
+  tags = {
+    application = var.stack_item_fullname
     managed_by  = "terraform"
-    Name        = "${length(var.lc_sg_name_prefix_override) > 0 ? var.lc_sg_name_prefix_override : format("%s-asg", var.stack_item_label)}"
+    Name        = length(var.lc_sg_name_prefix_override) > 0 ? var.lc_sg_name_prefix_override : format("%s-asg", var.stack_item_label)
   }
 
   lifecycle {
@@ -19,26 +19,29 @@ resource "aws_security_group" "sg_asg" {
 
 ## Creates launch configuration
 resource "aws_launch_configuration" "lc" {
-  count = "${length(var.ebs_vol_device_name) > 0 ? 0 : 1}"
+  count = length(var.ebs_vol_device_name) > 0 ? 0 : 1
 
-  associate_public_ip_address = "${var.associate_public_ip_address}"
-  ebs_optimized               = "${var.ebs_optimized}"
-  enable_monitoring           = "${var.enable_monitoring}"
-  iam_instance_profile        = "${var.instance_profile}"
-  image_id                    = "${var.ami}"
-  instance_type               = "${var.instance_type}"
-  key_name                    = "${var.key_name}"
+  associate_public_ip_address = var.associate_public_ip_address
+  ebs_optimized               = var.ebs_optimized
+  enable_monitoring           = var.enable_monitoring
+  iam_instance_profile        = var.instance_profile
+  image_id                    = var.ami
+  instance_type               = var.instance_type
+  key_name                    = var.key_name
   name_prefix                 = "${var.stack_item_label}-"
-  placement_tenancy           = "${var.placement_tenancy}"
-  security_groups             = ["${distinct(concat(list(aws_security_group.sg_asg.id), compact(var.security_groups)))}"]
-  spot_price                  = "${var.spot_price}"
-  user_data                   = "${var.user_data}"
+  placement_tenancy           = var.placement_tenancy
+  security_groups = distinct(
+    concat([aws_security_group.sg_asg.id], compact(var.security_groups)),
+  )
+  spot_price = var.spot_price
+  user_data  = var.user_data
 
   root_block_device {
-    delete_on_termination = "${var.root_vol_del_on_term}"
-    iops                  = "${var.root_vol_type == "io1" ? var.root_vol_iops : "0" }"
-    volume_size           = "${length(var.root_vol_size) > 0 ? var.root_vol_size : "8"}"
-    volume_type           = "${var.root_vol_type}"
+    delete_on_termination = var.root_vol_del_on_term
+    iops                  = var.root_vol_type == "io1" ? var.root_vol_iops : "0"
+    volume_size           = length(var.root_vol_size) > 0 ? var.root_vol_size : "8"
+    volume_type           = var.root_vol_type
+    encrypted             = var.root_vol_encrypted
   }
 
   lifecycle {
@@ -47,39 +50,42 @@ resource "aws_launch_configuration" "lc" {
 }
 
 resource "aws_launch_configuration" "lc_ebs" {
-  count = "${length(var.ebs_vol_device_name) > 0 ? 1 : 0}"
+  count = length(var.ebs_vol_device_name) > 0 ? 1 : 0
 
-  associate_public_ip_address = "${var.associate_public_ip_address}"
-  ebs_optimized               = "${var.ebs_optimized}"
-  enable_monitoring           = "${var.enable_monitoring}"
-  iam_instance_profile        = "${var.instance_profile}"
-  image_id                    = "${var.ami}"
-  instance_type               = "${var.instance_type}"
-  key_name                    = "${var.key_name}"
+  associate_public_ip_address = var.associate_public_ip_address
+  ebs_optimized               = var.ebs_optimized
+  enable_monitoring           = var.enable_monitoring
+  iam_instance_profile        = var.instance_profile
+  image_id                    = var.ami
+  instance_type               = var.instance_type
+  key_name                    = var.key_name
   name_prefix                 = "${var.stack_item_label}-"
-  placement_tenancy           = "${var.placement_tenancy}"
-  security_groups             = ["${distinct(concat(list(aws_security_group.sg_asg.id), compact(var.security_groups)))}"]
-  spot_price                  = "${var.spot_price}"
-  user_data                   = "${var.user_data}"
+  placement_tenancy           = var.placement_tenancy
+  security_groups = distinct(
+    concat([aws_security_group.sg_asg.id], compact(var.security_groups)),
+  )
+  spot_price = var.spot_price
+  user_data  = var.user_data
 
   root_block_device {
-    delete_on_termination = "${var.root_vol_del_on_term}"
-    iops                  = "${var.root_vol_type == "io1" ? var.root_vol_iops : "0" }"
-    volume_size           = "${length(var.root_vol_size) > 0 ? var.root_vol_size : "0"}"
-    volume_type           = "${var.root_vol_type}"
+    delete_on_termination = var.root_vol_del_on_term
+    iops                  = var.root_vol_type == "io1" ? var.root_vol_iops : "0"
+    volume_size           = length(var.root_vol_size) > 0 ? var.root_vol_size : "0"
+    volume_type           = var.root_vol_type
   }
 
   ebs_block_device {
-    delete_on_termination = "${var.ebs_vol_del_on_term}"
-    device_name           = "${var.ebs_vol_device_name}"
-    encrypted             = "${length(var.ebs_vol_snapshot_id) > 0 ? "" : var.ebs_vol_encrypted}"
-    iops                  = "${var.ebs_vol_type == "io1" ? var.ebs_vol_iops : "0" }"
-    snapshot_id           = "${var.ebs_vol_snapshot_id}"
-    volume_size           = "${length(var.ebs_vol_snapshot_id) > 0 ? "0" : var.ebs_vol_size}"
-    volume_type           = "${var.ebs_vol_type}"
+    delete_on_termination = var.ebs_vol_del_on_term
+    device_name           = var.ebs_vol_device_name
+    encrypted             = length(var.ebs_vol_snapshot_id) > 0 ? "" : var.ebs_vol_encrypted
+    iops                  = var.ebs_vol_type == "io1" ? var.ebs_vol_iops : "0"
+    snapshot_id           = var.ebs_vol_snapshot_id
+    volume_size           = length(var.ebs_vol_snapshot_id) > 0 ? "0" : var.ebs_vol_size
+    volume_type           = var.ebs_vol_type
   }
 
   lifecycle {
     create_before_destroy = true
   }
 }
+
diff --git a/group/lc/outputs.tf b/group/lc/outputs.tf
index 71b97af..5271632 100644
--- a/group/lc/outputs.tf
+++ b/group/lc/outputs.tf
@@ -1,9 +1,13 @@
 # Outputs
 
 output "lc_id" {
-  value = "${coalesce(join(",",aws_launch_configuration.lc.*.id),join(",",aws_launch_configuration.lc_ebs.*.id))}"
+  value = coalesce(
+    join(",", aws_launch_configuration.lc.*.id),
+    join(",", aws_launch_configuration.lc_ebs.*.id),
+  )
 }
 
 output "sg_id" {
-  value = "${aws_security_group.sg_asg.id}"
+  value = aws_security_group.sg_asg.id
 }
+
diff --git a/group/lc/variables.tf b/group/lc/variables.tf
index 12939b8..79d30d9 100644
--- a/group/lc/variables.tf
+++ b/group/lc/variables.tf
@@ -2,108 +2,114 @@
 
 ## Resource tags
 variable "stack_item_fullname" {
-  type = "string"
+  type = string
 }
 
 variable "stack_item_label" {
-  type = "string"
+  type = string
 }
 
 ## Allow override of resource naming
 variable "lc_sg_name_prefix_override" {
-  type = "string"
+  type = string
 }
 
 ## VPC parameters
 variable "vpc_id" {
-  type = "string"
+  type = string
 }
 
 ## LC parameters
 variable "associate_public_ip_address" {
-  type = "string"
+  type = string
 }
 
 variable "ami" {
-  type = "string"
+  type = string
 }
 
 variable "ebs_optimized" {
-  type = "string"
+  type = string
 }
 
 variable "ebs_vol_del_on_term" {
-  type = "string"
+  type = string
 }
 
 variable "ebs_vol_device_name" {
-  type = "string"
+  type = string
 }
 
 variable "ebs_vol_encrypted" {
-  type = "string"
+  type = string
 }
 
 variable "ebs_vol_snapshot_id" {
-  type = "string"
+  type = string
 }
 
 variable "ebs_vol_iops" {
-  type = "string"
+  type = string
 }
 
 variable "ebs_vol_size" {
-  type = "string"
+  type = string
 }
 
 variable "ebs_vol_type" {
-  type = "string"
+  type = string
 }
 
 variable "enable_monitoring" {
-  type = "string"
+  type = string
 }
 
 variable "instance_profile" {
-  type = "string"
+  type = string
 }
 
 variable "instance_type" {
-  type = "string"
+  type = string
 }
 
 variable "key_name" {
-  type = "string"
+  type = string
 }
 
 variable "placement_tenancy" {
-  type = "string"
+  type = string
 }
 
 variable "root_vol_del_on_term" {
-  type = "string"
+  type = string
 }
 
 variable "root_vol_iops" {
-  type = "string"
+  type = string
 }
 
 variable "root_vol_size" {
-  type = "string"
+  type = string
 }
 
 variable "root_vol_type" {
-  type = "string"
+  type = string
+}
+
+variable "root_vol_encrypted" {
+  type = bool
+  default = false
 }
 
 variable "security_groups" {
-  type = "list"
+  type = list(string)
 }
 
 variable "spot_price" {
-  type = "string"
+  type = string
 }
 
 variable "user_data" {
-  type = "string"
+  type = string
 }
+
diff --git a/group/lc/versions.tf b/group/lc/versions.tf
new file mode 100644
index 0000000..ac97c6a
--- /dev/null
+++ b/group/lc/versions.tf
@@ -0,0 +1,4 @@
+
+terraform {
+  required_version = ">= 0.12"
+}
diff --git a/group/main.tf b/group/main.tf
index b95cbd8..5292804 100644
--- a/group/main.tf
+++ b/group/main.tf
@@ -1,31 +1,27 @@
 # AWS Auto Scaling Configuration
 
-## Set Terraform version constraint
-terraform {
-  required_version = "> 0.8.0"
-}
-
 ## Creates cloudconfig fragments for tagging
-data "aws_region" "current" {}
+data "aws_region" "current" {
+}
 
 data "template_file" "name" {
-  template = "${var.instance_based_naming_enabled == "true" ? file("${path.module}/templates/name.tpl") : ""}"
+  template = var.instance_based_naming_enabled == "true" ? file("${path.module}/templates/name.tpl") : ""
 
-  vars {
-    name_prefix = "${length(var.instance_name_prefix) > 0 ? var.instance_name_prefix : var.stack_item_label}"
-    region      = "${data.aws_region.current.name}"
+  vars = {
+    name_prefix = length(var.instance_name_prefix) > 0 ? var.instance_name_prefix : var.stack_item_label
+    region      = data.aws_region.current.name
   }
 }
 
 data "template_file" "tags" {
-  count = "${length(keys(var.instance_tags))}"
+  count = length(keys(var.instance_tags))
 
-  template = "${element(keys(var.instance_tags),count.index) != "" ? file("${path.module}/templates/tag.tpl") : ""}"
+  template = element(keys(var.instance_tags), count.index) != "" ? file("${path.module}/templates/tag.tpl") : ""
 
-  vars {
-    key    = "${element(keys(var.instance_tags),count.index)}"
-    region = "${data.aws_region.current.name}"
-    value  = "${lookup(var.instance_tags,element(keys(var.instance_tags),count.index))}"
+  vars = {
+    key    = element(keys(var.instance_tags), count.index)
+    region = data.aws_region.current.name
+    value  = var.instance_tags[element(keys(var.instance_tags), count.index)]
   }
 }
 
@@ -35,95 +31,96 @@ data "template_cloudinit_config" "cloud_config" {
 
   part {
     content_type = "text/cloud-config"
-    content      = "${var.user_data}"
+    content      = var.user_data
   }
 
   part {
     content_type = "text/cloud-config"
-    content      = "${data.template_file.name.rendered}"
+    content      = data.template_file.name.rendered
     merge_type   = "list(append)+dict(recurse_array)+str()"
   }
 
   part {
     content_type = "text/cloud-config"
-    content      = "#cloud-config\nruncmd:\n${join("",data.template_file.tags.*.rendered)}"
+    content      = "#cloud-config\nruncmd:\n${join("", data.template_file.tags.*.rendered)}"
     merge_type   = "list(append)+dict(recurse_array)+str()"
   }
 }
 
 ## Creates launch configuration & security group
 module "lc" {
-  source = "lc"
+  source = "./lc"
 
   ### Resource labels
-  stack_item_fullname        = "${var.stack_item_fullname}"
-  stack_item_label           = "${var.stack_item_label}"
-  lc_sg_name_prefix_override = "${var.lc_sg_name_prefix_override}"
+  stack_item_fullname        = var.stack_item_fullname
+  stack_item_label           = var.stack_item_label
+  lc_sg_name_prefix_override = var.lc_sg_name_prefix_override
 
   ### VPC parameters
-  vpc_id = "${var.vpc_id}"
+  vpc_id = var.vpc_id
 
   ### LC parameters
-  ami                         = "${var.ami}"
-  associate_public_ip_address = "${var.associate_public_ip_address}"
-  ebs_optimized               = "${var.ebs_optimized}"
-  ebs_vol_del_on_term         = "${var.ebs_vol_del_on_term}"
-  ebs_vol_device_name         = "${var.ebs_vol_device_name}"
-  ebs_vol_encrypted           = "${var.ebs_vol_encrypted}"
-  ebs_vol_iops                = "${var.ebs_vol_iops}"
-  ebs_vol_size                = "${var.ebs_vol_size}"
-  ebs_vol_snapshot_id         = "${var.ebs_vol_snapshot_id}"
-  ebs_vol_type                = "${var.ebs_vol_type}"
-  enable_monitoring           = "${var.enable_monitoring}"
-  instance_profile            = "${var.instance_profile}"
-  instance_type               = "${var.instance_type}"
-  key_name                    = "${var.key_name}"
-  placement_tenancy           = "${var.placement_tenancy}"
-  root_vol_del_on_term        = "${var.root_vol_del_on_term}"
-  root_vol_iops               = "${var.root_vol_iops}"
-  root_vol_size               = "${var.root_vol_size}"
-  root_vol_type               = "${var.root_vol_type}"
-  security_groups             = ["${var.security_groups}"]
-  spot_price                  = "${var.spot_price}"
-  user_data                   = "${data.template_cloudinit_config.cloud_config.rendered}"
+  ami                         = var.ami
+  associate_public_ip_address = var.associate_public_ip_address
+  ebs_optimized               = var.ebs_optimized
+  ebs_vol_del_on_term         = var.ebs_vol_del_on_term
+  ebs_vol_device_name         = var.ebs_vol_device_name
+  ebs_vol_encrypted           = var.ebs_vol_encrypted
+  ebs_vol_iops                = var.ebs_vol_iops
+  ebs_vol_size                = var.ebs_vol_size
+  ebs_vol_snapshot_id         = var.ebs_vol_snapshot_id
+  ebs_vol_type                = var.ebs_vol_type
+  enable_monitoring           = var.enable_monitoring
+  instance_profile            = var.instance_profile
+  instance_type               = var.instance_type
+  key_name                    = var.key_name
+  placement_tenancy           = var.placement_tenancy
+  root_vol_del_on_term        = var.root_vol_del_on_term
+  root_vol_iops               = var.root_vol_iops
+  root_vol_size               = var.root_vol_size
+  root_vol_type               = var.root_vol_type
+  root_vol_encrypted          = var.root_vol_encrypted
+  security_groups             = var.security_groups
+  spot_price                  = var.spot_price
+  user_data                   = data.template_cloudinit_config.cloud_config.rendered
 }
 
 ## Creates auto scaling group
 module "asg" {
-  source = "asg"
+  source = "./asg"
 
   ### Resource tags
-  stack_item_label         = "${var.stack_item_label}"
-  stack_item_fullname      = "${var.stack_item_fullname}"
-  asg_name_override        = "${var.asg_name_override}"
-  propagate_name_at_launch = "${var.propagate_name_at_launch}"
+  stack_item_label         = var.stack_item_label
+  stack_item_fullname      = var.stack_item_fullname
+  asg_name_override        = var.asg_name_override
+  propagate_name_at_launch = var.propagate_name_at_launch
 
   ### VPC parameters
-  subnets = ["${var.subnets}"]
+  subnets = var.subnets
 
   ### LC parameters
-  lc_id = "${module.lc.lc_id}"
+  lc_id = module.lc.lc_id
 
   ### ASG parameters
-  default_cooldown          = "${var.default_cooldown}"
-  desired_capacity          = "${var.desired_capacity}"
-  enabled_metrics           = ["${var.enabled_metrics}"]
-  force_delete              = "${var.force_delete}"
-  hc_check_type             = "${var.hc_check_type}"
-  hc_grace_period           = "${var.hc_grace_period}"
-  max_size                  = "${var.max_size}"
+  default_cooldown          = var.default_cooldown
+  desired_capacity          = var.desired_capacity
+  enabled_metrics           = var.enabled_metrics
+  force_delete              = var.force_delete
+  hc_check_type             = var.hc_check_type
+  hc_grace_period           = var.hc_grace_period
+  max_size                  = var.max_size
   metrics_granularity       = "1Minute"
-  min_size                  = "${var.min_size}"
-  placement_group           = "${var.placement_group}"
-  protect_from_scale_in     = "${var.protect_from_scale_in}"
-  suspended_processes       = ["${var.suspended_processes}"]
-  termination_policies      = ["${var.termination_policies}"]
-  wait_for_capacity_timeout = "${var.wait_for_capacity_timeout}"
-  additional_asg_tags       = "${var.additional_asg_tags}"
+  min_size                  = var.min_size
+  placement_group           = var.placement_group
+  protect_from_scale_in     = var.protect_from_scale_in
+  suspended_processes       = var.suspended_processes
+  termination_policies      = var.termination_policies
+  wait_for_capacity_timeout = var.wait_for_capacity_timeout
+  additional_asg_tags       = var.additional_asg_tags
 
   ### ELB parameters
-  load_balancers        = ["${var.load_balancers}"]
-  min_elb_capacity      = "${var.min_elb_capacity}"
-  target_group_arns     = ["${var.target_group_arns}"]
-  wait_for_elb_capacity = "${var.wait_for_elb_capacity}"
+  load_balancers        = var.load_balancers
+  min_elb_capacity      = var.min_elb_capacity
+  target_group_arns     = var.target_group_arns
+  wait_for_elb_capacity = var.wait_for_elb_capacity
 }
diff --git a/group/outputs.tf b/group/outputs.tf
index 847616b..c4a3c9e 100644
--- a/group/outputs.tf
+++ b/group/outputs.tf
@@ -1,17 +1,18 @@
 # Outputs
 
 output "asg_id" {
-  value = "${module.asg.asg_id}"
+  value = module.asg.asg_id
 }
 
 output "asg_name" {
-  value = "${module.asg.asg_name}"
+  value = module.asg.asg_name
 }
 
 output "lc_id" {
-  value = "${module.lc.lc_id}"
+  value = module.lc.lc_id
 }
 
 output "sg_id" {
-  value = "${module.lc.sg_id}"
+  value = module.lc.sg_id
 }
+
diff --git a/group/variables.tf b/group/variables.tf
index 720e288..e416387 100644
--- a/group/variables.tf
+++ b/group/variables.tf
@@ -2,76 +2,76 @@
 
 ## Resource tags
 variable "stack_item_fullname" {
-  type        = "string"
+  type        = string
   description = "Long form descriptive name for this stack item. This value is used to create the 'application' resource tag for resources created by this stack item."
 }
 
 variable "stack_item_label" {
-  type        = "string"
+  type        = string
   description = "Short form identifier for this stack. This value is used to create the 'Name' resource tag for resources created by this stack item, and also serves as a unique key for re-use."
 }
 
 variable "asg_name_override" {
-  type        = "string"
+  type        = string
   description = "A string to override the ASG name"
   default     = ""
 }
 
 variable "lc_sg_name_prefix_override" {
-  type        = "string"
+  type        = string
   description = "A string to override the ASG name"
   default     = ""
 }
 
 variable "propagate_name_at_launch" {
-  type        = "string"
+  type        = string
   description = "A string to override the ASG name"
   default     = "true"
 }
 
 ## VPC parameters
 variable "subnets" {
-  type        = "list"
+  type        = list(string)
   description = "A list of subnet IDs to launch resources in"
 }
 
 variable "vpc_id" {
-  type        = "string"
+  type        = string
   description = "ID of the target VPC."
 }
 
 ## LC parameters
 variable "ami" {
-  type        = "string"
+  type        = string
   description = "Amazon Machine Image (AMI) to associate with the launch configuration."
 }
 
 variable "associate_public_ip_address" {
-  type        = "string"
+  type        = string
   description = "Flag for associating public IP addresses with instances managed by the auto scaling group."
   default     = ""
 }
 
 variable "ebs_optimized" {
-  type        = "string"
+  type        = string
   description = "Flag to enable EBS optimization."
   default     = "false"
 }
 
 variable "ebs_vol_del_on_term" {
-  type        = "string"
+  type        = string
   description = "Whether the volume should be destroyed on instance termination."
   default     = "true"
 }
 
 variable "ebs_vol_device_name" {
-  type        = "string"
+  type        = string
   description = "The name of the device to mount."
   default     = ""
 }
 
 variable "ebs_vol_encrypted" {
-  type        = "string"
+  type        = string
   description = "Whether the volume should be encrypted or not. Do not use this option if you are using 'snapshot_id' as the encrypted flag will be determined by the snapshot."
   default     = ""
 }
@@ -81,55 +81,55 @@ http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/EBSVolumeTypes.html
 For the best per-I/O latency experience, we recommend that you provision an IOPS-to-GiB ratio greater than 2:1. For example, a 2,000 IOPS volume should be smaller than 1,000 GiB.
 */
 variable "ebs_vol_iops" {
-  type        = "string"
+  type        = string
   description = "The amount of provisioned IOPS"
   default     = "2000"
 }
 
 variable "ebs_vol_size" {
-  type        = "string"
+  type        = string
   description = "The size of the volume in gigabytes."
   default     = ""
 }
 
 variable "ebs_vol_snapshot_id" {
-  type        = "string"
+  type        = string
   description = "The Snapshot ID to mount."
   default     = ""
 }
 
 variable "ebs_vol_type" {
-  type        = "string"
+  type        = string
   description = "The type of volume. Valid values are 'standard', 'gp2' and 'io1'."
   default     = "gp2"
 }
 
 variable "enable_monitoring" {
-  type        = "string"
+  type        = string
   description = "Flag to enable detailed monitoring."
   default     = ""
 }
 
 variable "instance_based_naming_enabled" {
-  type        = "string"
+  type        = string
   description = "Flag to enable instance-id based name tagging."
   default     = ""
 }
 
 variable "instance_name_prefix" {
-  type        = "string"
+  type        = string
   description = "Sring to prepend instance-id based name tags with."
   default     = ""
 }
 
 variable "instance_profile" {
-  type        = "string"
+  type        = string
   description = "IAM instance profile to associate with the launch configuration."
   default     = ""
 }
 
 variable "instance_tags" {
-  type        = "map"
+  type        = map(string)
   description = "Map of tags to add to isntances."
 
   default = {
@@ -138,24 +138,24 @@ variable "instance_tags" {
 }
 
 variable "instance_type" {
-  type        = "string"
+  type        = string
   description = "EC2 instance type to associate with the launch configuration."
 }
 
 variable "key_name" {
-  type        = "string"
+  type        = string
   description = "SSH key pair to associate with the launch configuration."
   default     = ""
 }
 
 variable "placement_tenancy" {
-  type        = "string"
+  type        = string
   description = "The tenancy of the instance. Valid values are 'default' or 'dedicated'."
   default     = "default"
 }
 
 variable "root_vol_del_on_term" {
-  type        = "string"
+  type        = string
   description = "Whether the volume should be destroyed on instance termination."
   default     = "true"
 }
@@ -165,145 +165,151 @@ http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/EBSVolumeTypes.html
 For the best per-I/O latency experience, we recommend that you provision an IOPS-to-GiB ratio greater than 2:1. For example, a 2,000 IOPS volume should be smaller than 1,000 GiB.
 */
 variable "root_vol_iops" {
-  type        = "string"
+  type        = string
   description = "The amount of provisioned IOPS"
   default     = "2000"
 }
 
 variable "root_vol_size" {
-  type        = "string"
+  type        = string
   description = "The size of the volume in gigabytes."
   default     = ""
 }
 
 variable "root_vol_type" {
-  type        = "string"
+  type        = string
   description = "The type of volume. Valid values are 'standard', 'gp2' and 'io1'."
   default     = "gp2"
 }
 
+variable "root_vol_encrypted" {
+  type = bool
+  default = false
+}
+
 variable "security_groups" {
-  type        = "list"
+  type        = list(string)
   description = "A list of associated security group IDs"
   default     = []
 }
 
 variable "spot_price" {
-  type        = "string"
+  type        = string
   description = "The price to use for reserving spot instances."
   default     = ""
 }
 
 variable "user_data" {
-  type        = "string"
+  type        = string
   description = "Instance initialization data to associate with the launch configuration."
   default     = ""
 }
 
 ## ASG parameters
 variable "additional_asg_tags" {
-  type        = "list"
+  type        = list(string)
   description = "Additional tags to apply at the ASG level, if any"
   default     = []
 }
 
 variable "default_cooldown" {
-  type        = "string"
+  type        = string
   description = "The amount of time, in seconds, after a scaling activity completes before another scaling activity can start."
   default     = ""
 }
 
 variable "desired_capacity" {
-  type        = "string"
+  type        = string
   description = "The number of Amazon EC2 instances that should be running in the group."
   default     = ""
 }
 
 variable "enabled_metrics" {
-  type        = "list"
+  type        = list(string)
   description = "A list of metrics to collect. The allowed values are 'GroupMinSize', 'GroupMaxSize', 'GroupDesiredCapacity', 'GroupInServiceInstances', 'GroupPendingInstances', 'GroupStandbyInstances', 'GroupTerminatingInstances', 'GroupTotalInstances'."
   default     = []
 }
 
 variable "force_delete" {
-  type        = "string"
+  type        = string
   description = "Flag to allow deletion of the auto scaling group without waiting for all instances in the pool to terminate."
   default     = "false"
 }
 
 variable "hc_check_type" {
-  type        = "string"
+  type        = string
   description = "Type of health check performed by the auto scaling group. Valid values are 'ELB' or 'EC2'."
   default     = ""
 }
 
 variable "hc_grace_period" {
-  type        = "string"
+  type        = string
   description = "Time allowed after an instance comes into service before checking health."
   default     = ""
 }
 
 variable "max_size" {
-  type        = "string"
+  type        = string
   description = "Maximum number of instances allowed by the auto scaling group."
 }
 
 variable "min_size" {
-  type        = "string"
+  type        = string
   description = "Minimum number of instance to be maintained by the auto scaling group."
 }
 
 variable "placement_group" {
-  type        = "string"
+  type        = string
   description = "The name of the placement group into which you'll launch your instances, if any."
   default     = ""
 }
 
 variable "protect_from_scale_in" {
-  type        = "string"
+  type        = bool
   description = "Allows setting instance protection. The autoscaling group will not select instances with this setting for terminination during scale in events."
-  default     = ""
+  default     = false
 }
 
 variable "suspended_processes" {
-  type        = "list"
+  type        = list(string)
   description = "A list of processes to suspend for the AutoScaling Group. The allowed values are 'Launch', 'Terminate', 'HealthCheck', 'ReplaceUnhealthy', 'AZRebalance', 'AlarmNotification', 'ScheduledActions', 'AddToLoadBalancer'. Note that if you suspend either the 'Launch' or 'Terminate' process types, it can prevent your autoscaling group from functioning properly."
   default     = []
 }
 
 variable "termination_policies" {
-  type        = "list"
+  type        = list(string)
   description = "A list of policies to decide how the instances in the auto scale group should be terminated. The allowed values are 'OldestInstance', 'NewestInstance', 'OldestLaunchConfiguration', 'ClosestToNextInstanceHour', 'Default'."
   default     = []
 }
 
 variable "wait_for_capacity_timeout" {
-  type        = "string"
+  type        = string
   description = "A maximum duration that Terraform should wait for ASG managed instances to become healthy before timing out."
   default     = ""
 }
 
 ## ELB parameters
 variable "load_balancers" {
-  type        = "list"
+  type        = list(string)
   description = "List of load balancer names to associate with the auto scaling group."
   default     = []
 }
 
 variable "min_elb_capacity" {
-  type        = "string"
+  type        = string
   description = "Minimum number of healthy instances attached to the ELB that must be maintained during updates."
   default     = ""
 }
 
 variable "target_group_arns" {
-  type        = "list"
+  type        = list(string)
   description = "A list of 'aws_alb_target_group' ARNs, for use with Application Load Balancing"
   default     = []
 }
 
 variable "wait_for_elb_capacity" {
-  type        = "string"
+  type        = string
   description = "Setting this will cause Terraform to wait for exactly this number of healthy instances in all attached load balancers on both create and update operations. (Takes precedence over 'min_elb_capacity' behavior.)"
   default     = ""
 }
+
diff --git a/group/versions.tf b/group/versions.tf
new file mode 100644
index 0000000..ac97c6a
--- /dev/null
+++ b/group/versions.tf
@@ -0,0 +1,4 @@
+
+terraform {
+  required_version = ">= 0.12"
+}