<p>I'm trying to call the SQL statement below but get the following error:</p>

<blockquote>
  <p>System.Data.SqlClient.SqlException: Conversion failed when converting
  the varchar value '+@buildingIDs+' to data type int.</p>
</blockquote>

<pre><code>@"SELECT id, startDateTime, endDateTime 
    FROM tb_bookings 
   WHERE buildingID IN ('+@buildingIDs+') 
     AND startDateTime &lt;= @fromDate";
</code></pre>

<p><code>buildingID</code> is an <code>int</code> type column in the db. Will I need to pass the IDs as an array of ints?</p>

It's trying to compare an int with the string value '+@buildingsIDs+'
So it tries to convert the string to convert it to an int and fails.
So do the following:
```
buildingsIDs = "1, 5, 6";
@"SELECT id, startDateTime, endDateTime From tb_bookings WHERE buildingID IN (" + buildingIDs + ") AND startDateTime <= @fromDate";
```