diff --git a/app/models/spree/variant.rb b/app/models/spree/variant.rb
index 1b2b085de1..8f61819708 100644
--- a/app/models/spree/variant.rb
+++ b/app/models/spree/variant.rb
@@ -79,6 +79,8 @@ module Spree
     after_create :create_stock_items
     after_create :set_position
 
+    before_save :convert_variant_weight_to_decimal
+
     around_destroy :destruction
 
     # default variant scope only lists non-deleted variants
@@ -243,5 +245,9 @@ module Spree
 
       self.unit_value = 1.0
     end
+
+    def convert_variant_weight_to_decimal
+      self.weight = weight.to_d
+    end
   end
 end
diff --git a/spec/models/spree/variant_spec.rb b/spec/models/spree/variant_spec.rb
index 548f82e1d8..73a1f79660 100644
--- a/spec/models/spree/variant_spec.rb
+++ b/spec/models/spree/variant_spec.rb
@@ -525,6 +525,38 @@ module Spree
           expect(product.master).to be_valid
         end
       end
+
+      context "when the product's unit is non-weight" do
+        before do
+          product.update_attribute :variant_unit, 'volume'
+          product.reload
+          variant.reload
+        end
+
+        it "sets weight to decimal before save if it's integer" do
+          variant.weight = 1
+          variant.save!
+          expect(variant.weight).to eq 1.0
+        end
+
+        it "sets weight to 0.0 before save if it's nil" do
+          variant.weight = nil
+          variant.save!
+          expect(variant.weight).to eq 0.0
+        end
+
+        it "sets weight to 0.0 if input is a non numerical string" do
+          variant.weight = "BANANAS!"
+          variant.save!
+          expect(variant.weight).to eq 0.0
+        end
+
+        it "sets weight to correct decimal value if input is numerical string" do
+          variant.weight = "2"
+          variant.save!
+          expect(variant.weight).to eq 2.0
+        end
+      end
     end
 
     describe "unit value/description" do