Not all compression-seal designs perform alike – it’s all in the hardware The key factor in a compression-seal profile de- sign is the type and amount of hardware applied. Multi-point locking is the most effective method of creating consistent pressure all around the sash and frame. The hardware is positioned on both the sash and frame so the gasket is compressed. With continuous and adequate pressure on the gasket, fairly equal contact between the sash and frame can be established and maintained. In fact, with multi-point locking, some windows with compression seals can be so effective they require pressure equalization – allowing air into the system at higher performance levels so any water that enters the system is capable of draining at an adequate rate. The bonus of multi-point locking is the added security against forced entry. “Very simply, knowledge is power,” Clavel added. “Having a good understanding of compres- sion-seal technology, how it works and what it of- fers to the entire project in the way of overall energy performance, is a definite advantage for an architect or engineer.” The Canadian Design and Construction Report — Spring 2013 – 55