diff --git a/src/layout.rs b/src/layout.rs
index c82fc404..193de93a 100644
--- a/src/layout.rs
+++ b/src/layout.rs
@@ -5,58 +5,128 @@ use crate::panes::PositionAndSize;
 
 fn split_space_to_parts_vertically(
     space_to_split: &PositionAndSize,
-    percentages: Vec<u8>,
+    sizes: Vec<Option<SplitSize>>,
 ) -> Vec<PositionAndSize> {
-    let mut split_parts = vec![];
+    let mut split_parts = Vec::new();
     let mut current_x_position = space_to_split.x;
-    let width = space_to_split.columns - (percentages.len() - 1); // minus space for gaps
-    for percentage in percentages.iter() {
-        let columns = (width as f32 * (*percentage as f32 / 100.0)) as usize; // TODO: round properly
+    let mut current_width = 0;
+    let max_width = space_to_split.columns - (sizes.len() - 1); // minus space for gaps
+
+    let mut parts_to_grow = Vec::new();
+
+    // First fit in the parameterized sizes
+    for size in sizes {
+        let columns = match size {
+            Some(SplitSize::Percent(percent)) => {
+                (max_width as f32 * (percent as f32 / 100.0)) as usize
+            } // TODO: round properly
+            Some(SplitSize::Fixed(size)) => size as usize,
+            None => {
+                parts_to_grow.push(current_x_position);
+                1 // This is grown later on
+            }
+        };
         split_parts.push(PositionAndSize {
             x: current_x_position,
             y: space_to_split.y,
             columns,
             rows: space_to_split.rows,
         });
+        current_width += columns;
         current_x_position += columns + 1; // 1 for gap
     }
-    let total_width = split_parts
-        .iter()
-        .fold(0, |total_width, part| total_width + part.columns);
-    if total_width < width {
-        // we have some extra space left, let's add it to the last part
-        let last_part_index = split_parts.len() - 1;
-        let mut last_part = split_parts.get_mut(last_part_index).unwrap();
-        last_part.columns += width - total_width;
+
+    if current_width > max_width {
+        panic!("Layout contained too many columns to fit onto the screen!");
+    }
+
+    let mut last_flexible_index = split_parts.len() - 1;
+    if let Some(new_columns) = (max_width - current_width).checked_div(parts_to_grow.len()) {
+        current_width = 0;
+        current_x_position = 0;
+        for (idx, part) in split_parts.iter_mut().enumerate() {
+            part.x = current_x_position;
+            if parts_to_grow.contains(&part.x) {
+                part.columns = new_columns;
+                last_flexible_index = idx;
+            }
+            current_width += part.columns;
+            current_x_position += part.columns + 1; // 1 for gap
+        }
+    }
+
+    if current_width < max_width {
+        // we have some extra space left, let's add it to the last flexible part
+        let extra = max_width - current_width;
+        let mut last_part = split_parts.get_mut(last_flexible_index).unwrap();
+        last_part.columns += extra;
+        for part in (&mut split_parts[last_flexible_index + 1..]).iter_mut() {
+            part.x += extra;
+        }
     }
     split_parts
 }
 
 fn split_space_to_parts_horizontally(
     space_to_split: &PositionAndSize,
-    percentages: Vec<u8>,
+    sizes: Vec<Option<SplitSize>>,
 ) -> Vec<PositionAndSize> {
-    let mut split_parts = vec![];
+    let mut split_parts = Vec::new();
     let mut current_y_position = space_to_split.y;
-    let height = space_to_split.rows - (percentages.len() - 1); // minus space for gaps
-    for percentage in percentages.iter() {
-        let rows = (height as f32 * (*percentage as f32 / 100.0)) as usize; // TODO: round properly
+    let mut current_height = 0;
+    let max_height = space_to_split.rows - (sizes.len() - 1); // minus space for gaps
+
+    let mut parts_to_grow = Vec::new();
+
+    for size in sizes {
+        let rows = match size {
+            Some(SplitSize::Percent(percent)) => {
+                (max_height as f32 * (percent as f32 / 100.0)) as usize
+            } // TODO: round properly
+            Some(SplitSize::Fixed(size)) => size as usize,
+            None => {
+                parts_to_grow.push(current_y_position);
+                1 // This is grown later on
+            }
+        };
         split_parts.push(PositionAndSize {
             x: space_to_split.x,
             y: current_y_position,
             columns: space_to_split.columns,
             rows,
         });
+        current_height += rows;
         current_y_position += rows + 1; // 1 for gap
     }
-    let total_height = split_parts
-        .iter()
-        .fold(0, |total_height, part| total_height + part.rows);
-    if total_height < height {
-        // we have some extra space left, let's add it to the last part
-        let last_part_index = split_parts.len() - 1;
-        let mut last_part = split_parts.get_mut(last_part_index).unwrap();
-        last_part.rows += height - total_height;
+
+    if current_height > max_height {
+        panic!("Layout contained too many rows to fit onto the screen!");
+    }
+
+    let mut last_flexible_index = split_parts.len() - 1;
+    if let Some(new_rows) = (max_height - current_height).checked_div(parts_to_grow.len()) {
+        current_height = 0;
+        current_y_position = 0;
+
+        for (idx, part) in split_parts.iter_mut().enumerate() {
+            part.y = current_y_position;
+            if parts_to_grow.contains(&part.y) {
+                part.rows = new_rows;
+                last_flexible_index = idx;
+            }
+            current_height += part.rows;
+            current_y_position += part.rows + 1; // 1 for gap
+        }
+    }
+
+    if current_height < max_height {
+        // we have some extra space left, let's add it to the last flexible part
+        let extra = max_height - current_height;
+        let mut last_part = split_parts.get_mut(last_flexible_index).unwrap();
+        last_part.rows += extra;
+        for part in (&mut split_parts[last_flexible_index + 1..]).iter_mut() {
+            part.y += extra;
+        }
     }
     split_parts
 }
@@ -66,24 +136,11 @@ fn split_space(
     layout: &Layout,
 ) -> Vec<(Layout, PositionAndSize)> {
     let mut pane_positions = Vec::new();
-    let percentages: Vec<u8> = layout
-        .parts
-        .iter()
-        .map(|part| {
-            let split_size = part.split_size.as_ref();
-            match split_size {
-                Some(SplitSize::Percent(percent)) => *percent,
-                None => {
-                    // TODO: if there is no split size, it should get the remaining "free space"
-                    panic!("Please enter the percentage of the screen part");
-                }
-            }
-        })
-        .collect();
+    let sizes: Vec<Option<SplitSize>> = layout.parts.iter().map(|part| part.split_size).collect();
 
     let split_parts = match layout.direction {
-        Direction::Vertical => split_space_to_parts_vertically(space_to_split, percentages),
-        Direction::Horizontal => split_space_to_parts_horizontally(space_to_split, percentages),
+        Direction::Vertical => split_space_to_parts_vertically(space_to_split, sizes),
+        Direction::Horizontal => split_space_to_parts_horizontally(space_to_split, sizes),
     };
     for (i, part) in layout.parts.iter().enumerate() {
         let part_position_and_size = split_parts.get(i).unwrap();
@@ -97,43 +154,16 @@ fn split_space(
     pane_positions
 }
 
-fn validate_layout_percentage_total(layout: &Layout) -> bool {
-    let total_percentages: u8 = layout
-        .parts
-        .iter()
-        .map(|part| {
-            let split_size = part.split_size.as_ref();
-            match split_size {
-                Some(SplitSize::Percent(percent)) => *percent,
-                None => {
-                    // TODO: if there is no split size, it should get the remaining "free space"
-                    panic!("Please enter the percentage of the screen part");
-                }
-            }
-        })
-        .sum();
-    if total_percentages != 100 {
-        return false;
-    }
-
-    for part in layout.parts.iter() {
-        if !part.parts.is_empty() {
-            return validate_layout_percentage_total(part);
-        }
-    }
-
-    true
-}
-
 #[derive(Debug, Serialize, Deserialize, Clone)]
 pub enum Direction {
     Horizontal,
     Vertical,
 }
 
-#[derive(Debug, Serialize, Deserialize, Clone)]
+#[derive(Debug, Serialize, Deserialize, Clone, Copy)]
 pub enum SplitSize {
     Percent(u8), // 1 to 100
+    Fixed(u16),  // An absolute number of columns or rows
 }
 
 #[derive(Debug, Serialize, Deserialize, Clone)]
@@ -158,17 +188,9 @@ impl Layout {
             .unwrap_or_else(|_| panic!("could not read layout {}", &layout_path.display()));
         let layout: Layout = serde_yaml::from_str(&layout)
             .unwrap_or_else(|_| panic!("could not parse layout {}", &layout_path.display()));
-        layout.validate();
-
         layout
     }
 
-    pub fn validate(&self) {
-        if !validate_layout_percentage_total(&self) {
-            panic!("The total percent for each part should equal 100.");
-        }
-    }
-
     pub fn total_terminal_panes(&self) -> usize {
         let mut total_panes = 0;
         total_panes += self.parts.len();
diff --git a/src/tests/fixtures/layouts/panes-with-plugins.yaml b/src/tests/fixtures/layouts/panes-with-plugins.yaml
index 7fb13b2e..9bb35e08 100644
--- a/src/tests/fixtures/layouts/panes-with-plugins.yaml
+++ b/src/tests/fixtures/layouts/panes-with-plugins.yaml
@@ -8,10 +8,6 @@ parts:
           Percent: 20
         plugin: strider.wasm
       - direction: Horizontal
-        split_size:
-          Percent: 80
-    split_size:
-      Percent: 80
   - direction: Vertical
     split_size:
-      Percent: 20
\ No newline at end of file
+      Fixed: 1
\ No newline at end of file
diff --git a/src/tests/integration/layouts.rs b/src/tests/integration/layouts.rs
index 35ff7188..2086ac72 100644
--- a/src/tests/integration/layouts.rs
+++ b/src/tests/integration/layouts.rs
@@ -50,43 +50,3 @@ pub fn accepts_basic_layout() {
     assert_snapshot!(next_to_last_snapshot);
     assert_snapshot!(last_snapshot);
 }
-
-#[test]
-#[should_panic(expected = "The total percent for each part should equal 100.")]
-pub fn should_throw_for_more_than_100_percent_total() {
-    let fake_win_size = PositionAndSize {
-        columns: 121,
-        rows: 20,
-        x: 0,
-        y: 0,
-    };
-    let mut fake_input_output = get_fake_os_input(&fake_win_size);
-    fake_input_output.add_terminal_input(&[&QUIT]);
-
-    let mut opts = CliArgs::default();
-    opts.layout = Some(PathBuf::from(
-        "src/tests/fixtures/layouts/parts-total-more-than-100-percent.yaml",
-    ));
-
-    start(Box::new(fake_input_output.clone()), opts);
-}
-
-#[test]
-#[should_panic(expected = "The total percent for each part should equal 100.")]
-pub fn should_throw_for_less_than_100_percent_total() {
-    let fake_win_size = PositionAndSize {
-        columns: 121,
-        rows: 20,
-        x: 0,
-        y: 0,
-    };
-    let mut fake_input_output = get_fake_os_input(&fake_win_size);
-    fake_input_output.add_terminal_input(&[&QUIT]);
-
-    let mut opts = CliArgs::default();
-    opts.layout = Some(PathBuf::from(
-        "src/tests/fixtures/layouts/parts-total-less-than-100-percent.yaml",
-    ));
-
-    start(Box::new(fake_input_output.clone()), opts);
-}