Last week we buttoned up the back bedroom and nearly finished off the back bathroom. This week, well, not much happened around the house. Over the weekend, Oceana’s parents and grandmother flew in to Miami to stay with Oceana’s sister, Isla, for a few days. We headed down to Miami for a few days to visit and to campervan in their driveway. We brought along Teak who enjoyed way too much play time with their two dogs. It was a nice visit and good to see everyone again.
A/C lines sweating
Do you remember the problem we were having with the A/C lines sweating in the small attic space over the master bathroom? Well, I finally figured out the cause and implemented a working solution. To recap, there’s a tiny attic space over the master bathroom which is sandwiched between the front and back bedrooms. In this attic space are the linesets that service the two air conditioning units for the bedrooms. The lines were dripping with condensation enough to where it was causing issues with the drywall. I ended up cutting out a bunch of drywall and insulating the lines. That really helped, but it didn’t solve the problem.
I watched the changing humidity
To understand what was happening, I installed multiple hygrometers in the attic and other areas of the bathroom and bedrooms. After watching the humidity in various areas for a few weeks, I started to get a feel for how the house changed in humidity. What I saw was that around 10am, when the sun hit that part of the roof over the attic for the first time that day, the humidity spiked in the attic. The gauge would max out at 100% and the framing up there would feel slightly damp. It seems like when the sun hits the roof, it causes the framing to sweat. That brings up the humidity in the attic area. Since it’s a tiny closed in attic, there’s no ventilation to get rid of the moisture, so it builds up and condenses on the easiest/coldest thing – the A/C linesets.
No ventilation
That means that the linesets sweating doesn’t really have much to do with the linesets but more so with ventilation. For instance, I ran the same linesets in the main attic without extra insulation and they are not sweating. The main attic has good ventilation.
The solution
Here’s my solution: I found a humidity activated relay switch and set it up to control a small 4″ fan. I’m going to duct the intake in from the back bedroom and then cut some slots in the access door over the A/C unit to let the air escape. I’ll have ductwork from the fan to the far side of the attic space to push cool, dry air to the furthest points of the attic and from there it will go out the return in the attic access door and back into the bedroom. So as the attic starts to sweat, the humidistat kicks the fan on which moves enough air in the attic to keep it dried out. I’ve had this system set up and running for a month or two now and there have been no further issues. That was a tough one! I’m looking forward to getting the drywall in the bathroom put back up and painted so we can have a normal nice bathroom again.
That’s all, folks
That’s all for this week. I’ll be picking up the corian sink today so I’m hopeful that the back bathroom will be wrapped up this week. As always, thanks for following along. Enjoy a few pictures of teak before you go.
HELLO