What the work is
Ducts in an unconditioned attic leak into the hottest space in the house. Every cubic foot that escapes is cooling you generated, paid for, and then threw away, and it also pulls hot attic air back in through the return side.
We find the leaks, seal the joints and boots with mastic rather than cloth tape, and repair or replace runs that are crushed, disconnected or too small to carry what the system is trying to push through them.
This is often the fix for the room that will not cool, and it costs a fraction of the bigger system that gets recommended instead.
How we find them: pressurise the duct system and look for where it will not hold, then confirm by hand at the joints and boots. The usual offenders are boots at the register, where the duct meets the ceiling, and the plenum connections at the equipment.
The other half of the job is balance. Sealing a leaky system changes the pressure everywhere in it, so registers that were roughly right can end up over- or under-served. We measure the rooms afterwards and adjust, because a sealed system that now overcools the front bedroom has moved the problem rather than fixed it.
What is included
- The leaks found and shown to you before they are sealed
- Mastic on joints, boots and plenums
- Crushed or disconnected runs repaired or replaced
- The registers checked for what they actually deliver afterwards
- Room registers measured after sealing, and dampers adjusted
What is not
- Cloth duct tape, which fails in an attic and is why some of these joints are open in the first place
- Full duct replacement, which is a separate quote after we have looked
What to ask anyone quoting this, us included
- Where were the leaks, and can you show me?
- What are you sealing them with?
- Will you measure the room afterwards?
- Will you measure the rooms after you seal?
- How did you find the leaks?