If you are considering replacing your old windows with new PVC windows, it is more than likely that you will also need a lintel installed. This should be done before the new windows are measured in case the brickwork needs to be altered. Quite often, the brickwork in traditional homes was laid across the timber windows, which meant that it did not matter if the brickwork above the window did not line up with the mortar joints. When installing a new lintel, it must sit across the brickwork above the window to support the weight above. This means alterations to the brickwork may be necessary. However, with proper planning and execution, installing a lintel should not be a difficult task. As always, if you have any doubts or concerns, it is best to consult with a professional before undertaking any work on your home.