Friday, June 19, 2009

Attic Mayhem

Simply put, your roof and attic are the most important parts of your house - anything else is just extra stuff holding the roof and attic up. The whole purpose for a house is to be a place to live in that will protect you and your stuff from the weather, and your attic and roof are what does almost all of the protecting. The roof keeps rain out of your attic, and your attic keeps the house at a reasonable temperature.
The attic keeps the heat in your house during winter, and the heat out during summer. The attic will get extremely hot during the summer, from the sun heating up those dark-colored asphalt based shingles. It will retain that heat long into the night, forcing you to run your A/C a lot longer. There are three solutions to this problem:

1) Vent the attic, get that hot air out of there.

There are many ways to vent your attic, and it can get pretty complicated if your roof is a complex shape. If your roof was properly built in the first place, it's designed so that cold air comes in from the soffits (vents under the overhang of your roof) and flows out through a vent at the top of the roof, allowing a constant "wash" of cold air over the underside of the roof. If you have a crappy old house, like I do, you might just need to install vents and an exhaust fan. Click here for some pictures and demonstrations about what I am describing. This is also important for keeping moisture out of the attic.

If you have mold, mildew, and rusting nails in the attic, it's probably not venting moisture well enough.

2) Insulate the attic, or separating your living area from the inferno over your head.

This is the most important part of your house to insulate. Here is where the heat of the sun is kept out during summer, and the heat from your heater is kept in during winter. Different areas have different standards for how much insulation goes into your attic, for example, in Maryland the standards are:

- Attic: (Green: R-49) (Std: R-38)
- Floor: (Green: R-30) (Std: R-25)
- Exterior walls: (Green: R-18 to R-22) (Std: 13)
- Unventilated Crawl spaces: (Green: R-25) (Std: R-19)
- Basement walls: (Green: R-25) (Std R-11)

You can see that the attic calls for the highest R-value of insulation in the house.

You have a lot of options for how to insulate the attic, If your attic is pretty open and square, like mine, you can use rolls of fiberglass, or you can use blow-in insulation (for those hard to reach areas, or if you're too lazy to roll out the fiberglass). Another option is spray-in insulation, it's expensive but is supposed to be the most effective.

You don't want to compress the insulation once it is in, the air inside the insulation is one of the things that gives it such great insulating properties.

Use a mask when laying fiberglass, and rub all exposed skin with baby powder before starting work, it makes the glass much less likely to stick to you and saves you tons of itching. I tried this, it works.

3)Reject heat before it even gets into the attic.

Don't use black shingles, they soak up the sun. If you already have them, many companies offer a aluminum-based silver paint that not only protects your roof, but helps reflect heat away from your house.

If your roof is the right shape, it will reflect and focus the heat onto your neighbors house, causing it to explode. Wear eye protection.

Now, if you're one of those idiots who bought a really small house with no space to store anything (like myself), then you probably want to turn your unfinished attic into storage space. That is what I chose to do, because the roof is so low you can't even stand up in the middle of the attic - turning it into living space would be pointless, wasteful, and cruel to your guests if you turn it into a guest room. I went to Home Depot (boo) and grabbed the cheapest flat wood I could find that would still hold my weight - half inch OSB (chip board) at $5.22 per 4x8 sheet. I had them chop it in half into 2x8 sheets to make it easier to transport and manage (it's free to have them cut your wood).
My house is divided into two sections, the addition, and the old house. The addition has proper 2x6 supports and is very sturdy. I simply put the OSB down and nailed it in place, sometimes notching the edges to allow a wire through. The old house has 3x3 beams, and is not even remotely sturdy. There are many solutions, but I just wanted storage space. So I made supports by cutting a 2x4 to fit and screwed one end into the joist (the 3x3 beam I was going to be standing on) and screwed the other end into a rafter (the slanted beams holding up the roof deck). Then I notched the OSB to fit around the new supports.

Now I have a floor I can walk on and store stuff on in the attic.

My friend Mark did most of the measuring and cutting for me, everyone needs a Mark. They may be out of stock of Mark at Harbor Freight, check back in the future.


DeLocus System: Blog Division said...

Try upgrading to a solar roof vent. Let the sun that is heating the attic do all the work for you. You get a lowered electric bill and a tax credit!

Anonymous said...

We have a spare mark, would you like him?