The photo below is of an installed length of aluminum semi-rigid duct which is located in the space between the roof and the suspended ceiling (with ceiling tiles). It branches off from the insulated rigid trunk of heating ductwork also located up that that area. From that main rigid branch the other end of the flex is connected to the ceiling register (or diffuser whichever it's typically called) installed into the suspended ceiling approximately a distance of only 4-5 feet. However, the original installer chose to use an excessively long length of this flex duct, probably a good 12-14 feet, to connect between the two points (the photograph clearly shows the indirect routing, how it snakes and curls up and around and then back down). My plan is to cut the flex shorter and reinstall between the two points. My inquiry here is what's a good method to measure the distance between the two offset points so that when I cut the flex I don't cut it too short but yet don't end up with it still unnecessarily longer than it needs to be, so the expandable "accordian" aspect of the flex material is stretched out to it's maximum reasonable/proper more ideal intended installation expansion.

We bought a 1350 square foot house a couple of months ago. The house was built 1994, and it has a Trane central air conditioning unit that's 4 years old. We have no complaints except in the Master Bedroom. It feels warmer than the rest of the house. I've moved an outdoor thermometer from room to room, and the temperature registers the same throughout the house, but anyone who enters the room can tell the difference in temperature. That makes no sense! Yesterday, we had a gentleman come out who works for a heating and cooling company. He was nice enough to come on his day off and analyze the problem for us. He had a gadget that gauged how much air was blowing from the vents. The vent in the laundry room (closest vent to the unit) was blowing at twice the recommended amount. (He told us the recommended amount was about 500. I don't remember what the unit of measure was.) The vent in the kitchen (the next closest room to the unit) was blowing at about 3 times that recommended amount. The living room (off the kitchen) was blowing above normal as well. All of the other rooms (except one family member's bedroom which does not feel hotter than the others) were blowing right at 500. The family member's bedroom was blowing at about 315, but the temperature feels fine in that room. The gentleman who came out had originally thought dampers might do the trick, but after measuring the air flow, he said he thinks Master Bedroom needs another line off the trunk so that he could add an air vent in the room. The Master Bedroom is 11X17, and it has just one air vent. However, the living room is much larger than that and has a vaulted ceiling, but just one air vent and is quite comfortable. The Master Bedroom is the only room in the house that faces South. Don't know if that matters. I've tried closing the blinds and black out curtains to keep it cooler, but that hasn't helped. Any thoughts or suggestions on what might be done or something we could do ourselves to make the Master Bedroom more comfortable without adding a window unit air conditioner? Thank you!