Unfortunately, most furnace filters are slid in place without an airtight seal, which allows air to pass around the filters. This problem is worse for the higher-efficiency MERV filters because of the increase in air resistance.
Common Cause is a network of people working to help rebalance cultural values to create a more equitable, sustainable and democratic society. 1  We are all shaped by our culture.
There are four causes: 1  Material cause, or the elements out of which an object is created; 2  Efficient cause, or the means by which it is created; 3  Formal cause, or the expression of what it is;  Final cause, or the end for which it is.