Proper storage of Milgard products is essential in ensuring they remain damage-free as they await final installation. Below are some helpful considerations for storing units in high temperatures in addition to guidance on product labels.
Vinyl windows and doors of any color should not be stored directly in the sun as it can cause temperatures >150º in less than 1 hour.
Units should be stored in a shaded area and on a flat base, as stated on the product label.
If you must stack units, offset the product to allow adequate ventilation, and do not stack more than five units deep. Suppose you store five or more 4040 picture windows in a row with no ventilation space. In that case, the Low-E glass will trap heat between units and act as an oven, accelerating temperature damage.
The most significant concern of high heat and direct sunlight exposure is the concentrated solar heat build-up on the vinyl frame. Temperatures of >150ºF can cause distortion, bubbling, and shrinkage. 150ºF+ surface temperatures are common in units not stored vertically and in direct sunlight. In these conditions, damaging surface temperatures can be reached in under 1 hour.