diff --git a/sacc/sacc.py b/sacc/sacc.py
index 7ef40eb..935fe9e 100644
--- a/sacc/sacc.py
+++ b/sacc/sacc.py
@@ -8,7 +8,7 @@
 from astropy.table import Table
 
 from .tracers import BaseTracer
-from .windows import BaseWindow, BandpowerWindow
+from .windows import BaseWindow, BandpowerWindow, TopHatWindow
 from .covariance import BaseCovariance, concatenate_covariances
 from .utils import unique_list
 from .data_types import standard_types, DataPoint
@@ -970,13 +970,8 @@ def get_bandpower_windows(self, indices):
                              "tracers and data type) or get windows "
                              "later.")
         ws = ws[0]
-        if not isinstance(ws, BandpowerWindow):
-            warnings.warn("No bandpower windows associated to these data")
-            return None
-        else:
-            w_inds = np.array(self._get_tags_by_index(['window_ind'],
-                                                      indices)[0])
-            return ws.get_section(w_inds)
+        w_inds = np.array(self._get_tags_by_index(['window_ind'], indices)[0])
+        return ws.get_section(w_inds)
 
     def get_ell_cl(self, data_type, tracer1, tracer2,
                    return_cov=False, return_ind=False):
@@ -1200,12 +1195,13 @@ def add_ell_cl(self, data_type, tracer1, tracer2, ell, x,
         None
 
         """
-        if isinstance(window, BandpowerWindow):
-            if len(ell) != window.nv:
+        if isinstance(window, (BandpowerWindow, TopHatWindow)):
+            nv = window.nv if isinstance(window, BandpowerWindow) else len(window.min)
+            if len(ell) != nv:
                 raise ValueError("Input bandpowers are misshapen")
-            tag_extra = range(window.nv)
+            tag_extra = range(nv)
             tag_extra_name = "window_ind"
-            window_use = [window for i in range(window.nv)]
+            window_use = [window for i in range(nv)]
         else:
             tag_extra = None
             tag_extra_name = None
diff --git a/sacc/windows.py b/sacc/windows.py
index 4f7fcec..7085159 100644
--- a/sacc/windows.py
+++ b/sacc/windows.py
@@ -1,3 +1,5 @@
+import warnings
+
 import numpy as np
 from astropy.table import Table
 
@@ -78,6 +80,23 @@ def from_tables(cls, table_list):
             windows.update(subclass.from_table(table))
         return windows
 
+    def get_section(self, indices):
+        """Get part of this window function corresponding to the input
+        indices.
+
+        Parameters
+        ----------
+        indices: int or array_like
+            Indices to return.
+
+        Returns
+        -------
+        window: `Window`
+            A `Window object.
+        """
+        warnings.warn("No bandpower windows associated to these data")
+        return None
+
 
 class TopHatWindow(BaseWindow, window_type='TopHat'):
     """A window function that is constant between two values.
@@ -158,6 +177,8 @@ def from_table(cls, table):
         """
         return {row['id']: cls(row['min'], row['max']) for row in table}
 
+    def get_section(self, indices):
+        return self.__class__(self.min[indices], self.max[indices])
 
 class LogTopHatWindow(TopHatWindow, window_type='LogTopHat'):
     """A window function that is log-constant between two values.
@@ -317,17 +338,4 @@ def from_table(cls, table):
         return {table.meta['SACCNAME']: cls(table['values'], table['weight'])}
 
     def get_section(self, indices):
-        """Get part of this window function corresponding to the input
-        indices.
-
-        Parameters
-        ----------
-        indices: int or array_like
-            Indices to return.
-
-        Returns
-        -------
-        window: `Window`
-            A `Window object.
-        """
         return self.__class__(self.values, self.weight[:, indices])