Starting my garage project - heat and insulation (door)

[mooch91]

All,

I'm an automotive enthusiast and I love spending time in the garage, and I'm going to be starting my garage project to get my space fully functional.

For background, I have a 900 sq ft 3-car attached garage in a house built in 2008 (well built, I might add). I'm located in central PA. I keep one truck, one SUV, and one car in the garage year-round.

The attic space above the garage is well insulated, as are the walls. The garage is fully finished and painted, with baseboard moldings and all. I have two drains in the garage floor (which should be good as I like washing my cars in the winter, looking to eventually be able to do this in the garage).

The garage is always about 20-25 degrees warmer than outside conditions in the winter. It never gets to freezing (32), but it gets close (38) on days where we have sub-freezing temperatures for a stretch. Most of the time it's a little too cool to work comfortably in the winter (and too warm to work comfortably in the hottest part of summer).

My first step is heat and insulation. I have one 16' and one 8' Clopay door. I called Clopay today to find out that they are their entry-level insulated doors, with an R-value of 6.3. There are foam boards on the back of the door, but they don't appear to be very thick (there's at least 1/4" of additional depth in the door cavities and the foam flops a bit.

I have on order the brush seals for the inside edge of the doors. The doors are well fitted, and the seals on the outside are tight, but the door does move a little in the wind and I can see some daylight near the bottom corners of the doors. For $100, I thought this would be a sensible upgrade.

I am seriously contemplating a mini-split heat pump for the garage, but I'm concerning myself with the insulation first, particularly the door.

The cost of two new doors is much higher than my budget allows, so I am looking for those who have experience adding insulation to an already insulated door.

Would you remove the current foam panels and replace them with something thicker (higher R-value)?

Would you add the "bubble wrap" Reflectix roll insulation (looks like it could be cut to fit neatly in to the cavities) as an alternative?

Or just go with the heat the way it is?

Thanks in advance for any thoughts.

 

[gnpenning]

This past week there has been a thread on reflectix insulation, you should read.

The current insulation is about as good as you are going to get in that style of door.

On the vertical track you have some stand off brackets that have adjustments to move your door closer to the weather strip. Some are riveted and need to be drilled out and new carriage bolts installed. Also depending on your rollers you may need to upgrade them to make up for some play between the track. DO NOT UNBOLT THE BOTTOM ROLLER BRACKET WHILE THE SPRINGS ARE UNDER TENSION. A new bottom seal that is longer may help with the daylight in your corners.

When you pull your vehicles in, the heat off the motor is helping to keep the garage warm year round. A mini split will help year round.

 

[Firebrick43]

Reflective insulation is only useful if it reflects back into an airspace. The foil face, if faced back into the garage, would do some good. If you place it anywhere else or paint then the reflective surface does nothing. The bubble part is little more than a condensation blanket. The r values stated are as whimsical and truthful as unicorn farts.

I personally would use a foil faced polyiso insulation for the best performance. As thick as would fit and use some foam adheasive to secure in the cavities. Green hinges, brush seals, and a new bottom seal will do even more.

A mini split with a low cutout temp is probably as good as solution as any for your garage.

 

[BoostAddiction]

I think that the level of insulation you have (and despite the manufacturer's claims, it likely isn't anywhere near R6) is probably fine for a garage door- and that the real low-hanging fruit is sealing.

The brush seals are a start, and if you have the right kind of door hardware, the Green Hinges are a great solution to keeping the door tight against the seals.

I have a similar space, and with "insulated" doors, and some OK sealing, my 2-ton minisplit does a fantastic job, in both cooling and heating.

 

[NUTTSGT]

I have some wood wedges on the doors of my garage. Keep in mind they don't get opened very often and the wedges need to be removed before opening. I stick them in the door latches which also have locks so it's a 1-2-3 details to open the door. The wedges do help close the gap up between the door and door frame.

When you add the polyiso, like Firebrick mentioned and I would also recommend, that you may need to bevel the edges or leave gaps for insulation as the door goes up.