two weights are required to balance one sash (upper or lower).
It is always more accurate to weigh your sashes (a bathroom scales will do) and input the weights into the calculator. We will calculate the weights for you, but you can overwrite that with your actual weights.
Give your sashes a reference and we will print it on your delivery note.
The value of A must be less than B + C – 25mm.
It is important to check that your sash window box can accommodate the weight sections of either 40mm, 45mm or 50mm.
It is also important to check that your sash window box can accommodate the length of the weights we calculate. Steel weights are longer than lead weights. The Lengths stated are subject to a tolerance of +/1 3mm