Does the calculator subtract door and window openings automatically?

Yes, entering your opening dimensions allows the calculator to net them out of the gross wall area before converting to a brick or block count, since ignoring openings is one of the most common reasons owners over-order material. Make sure you enter every significant opening, including ventilators and smaller windows, since these add up across a full house. Leaving openings out of your input will inflate your estimate and lead to unused material sitting on site.