diff --git a/lib/wibox/layout/flex.lua b/lib/wibox/layout/flex.lua
index d2330031..47d983c4 100644
--- a/lib/wibox/layout/flex.lua
+++ b/lib/wibox/layout/flex.lua
@@ -23,7 +23,7 @@ end
 -- @param height The available height.
 function flex:layout(context, width, height)
     local result = {}
-    local pos,spacing = 0,self._spacing or 0
+    local pos,spacing = 0, self._spacing
     local num = #self.widgets
     local total_spacing = (spacing*(num-1))
 
@@ -88,7 +88,7 @@ function flex:fit(context, orig_width, orig_height)
             #self.widgets * self._max_widget_size)
     end
 
-    local spacing = ((self._spacing or 0)*(#self.widgets-1))
+    local spacing = self._spacing * (#self.widgets-1)
 
     if self.dir == "y" then
         return used_in_other, used_in_dir + spacing
@@ -106,15 +106,19 @@ end
 -- maximum width for horizontal and maximum height for vertical).
 -- @param val The maximum size of the widget.
 function flex:set_max_widget_size(val)
-    self._max_widget_size = val
-    self:emit_signal("widget::layout_changed")
+    if self._max_widget_size ~= val then
+        self._max_widget_size = val
+        self:emit_signal("widget::layout_changed")
+    end
 end
 
 --- Add spacing between each layout widgets
 -- @param spacing Spacing between widgets.
 function flex:set_spacing(spacing)
-    self._spacing = spacing
-    self:emit_signal("widget::layout_changed")
+    if self._spacing ~= spacing then
+        self._spacing = spacing
+        self:emit_signal("widget::layout_changed")
+    end
 end
 
 function flex:reset()
@@ -134,6 +138,7 @@ local function get_layout(dir)
 
     ret.dir = dir
     ret.widgets = {}
+    ret:set_spacing(0)
 
     return ret
 end
diff --git a/spec/wibox/layout/flex_spec.lua b/spec/wibox/layout/flex_spec.lua
index 9f0e698a..ac83500a 100644
--- a/spec/wibox/layout/flex_spec.lua
+++ b/spec/wibox/layout/flex_spec.lua
@@ -4,6 +4,7 @@
 ---------------------------------------------------------------------------
 
 local flex = require("wibox.layout.flex")
+local base = require("wibox.widget.base")
 local utils = require("wibox.test_utils")
 local p = require("wibox.widget.base").place_widget_at
 
@@ -76,6 +77,59 @@ describe("wibox.layout.flex", function()
             end)
         end)
     end)
+
+    describe("emitting signals", function()
+        local layout_changed
+        before_each(function()
+            layout:connect_signal("widget::layout_changed", function()
+                layout_changed = layout_changed + 1
+            end)
+            layout_changed = 0
+        end)
+
+        it("add", function()
+            local w1, w2 = base.empty_widget(), base.empty_widget()
+            assert.is.equal(layout_changed, 0)
+            layout:add(w1)
+            assert.is.equal(layout_changed, 1)
+            layout:add(w2)
+            assert.is.equal(layout_changed, 2)
+            layout:add(w2)
+            assert.is.equal(layout_changed, 3)
+        end)
+
+        it("reset", function()
+            assert.is.equal(layout_changed, 0)
+            layout:add(base.make_widget())
+            assert.is.equal(layout_changed, 1)
+            layout:reset()
+            assert.is.equal(layout_changed, 2)
+        end)
+
+        it("set_spacing", function()
+            assert.is.equal(layout_changed, 0)
+            layout:set_spacing(0)
+            assert.is.equal(layout_changed, 0)
+            layout:set_spacing(5)
+            assert.is.equal(layout_changed, 1)
+            layout:set_spacing(2)
+            assert.is.equal(layout_changed, 2)
+            layout:set_spacing(2)
+            assert.is.equal(layout_changed, 2)
+        end)
+
+        it("set_max_widget_size", function()
+            assert.is.equal(layout_changed, 0)
+            layout:set_max_widget_size(nil)
+            assert.is.equal(layout_changed, 0)
+            layout:set_max_widget_size(20)
+            assert.is.equal(layout_changed, 1)
+            layout:set_max_widget_size(20)
+            assert.is.equal(layout_changed, 1)
+            layout:set_max_widget_size(nil)
+            assert.is.equal(layout_changed, 2)
+        end)
+    end)
 end)
 
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