Roof insulation on the cheap?

[kf4zht]

Here's the story. I rent a house in Statesboro, GA, where I go to school. It gets very hot here, typically 95+ and high humidity. The house we rent has a 2 car garage, but do the the way it faces and the lack of a vent fan of any kind it gets hot very quick and is unbearable to be in during the day. It is usually hotter than out in the sun.

We want to insulate it, but as we are college students, and its a rental we don't have that much to put into it. Right now there is no insulation of any kind. The ceiling is open rafter, 2x6s I think. It slopes up in one direction to meet the roofline of the house. The walls are standard 2x4 with plywood sheeting on them. Right now we are just looking at doing the ceiling, I have a feeling that the hot sun on a black roof with no insulation is the big part of our problem. Our landlord is fine with almost anything we do to the house, as long as it is structurally sound and done correctly.

Now I priced out R-19 batted as about 40-50 cents a square foot, R30 was about 70-80 cents.

I saw the attic foil stuff, would that work on its own?

Also I know we need a fan, also to clear out welding fumes in the winter when we close it up. Who makes a good fan we can install in the top area, preferably a good value?

 

[gesoffen]

WHen you say open rafter, do you mean there is no drywall on what would be the joists or do you mean there are no joists (i.e. a cathedral style ceiling)? If you mean the former, you'd have to drywall the underside of the joists and insulate on top. If you mean the latter, you'll can insulate the rafter cavities but you have to be very careful to allow a ventilation path between the insulation and the underside of the roof sheathing in order to prevent ice daming, mold/mildew/condensation damage ,etc (assuming this is a traditional hot roof design).

Short summary is there is nothing cheap to do unless you get the materials free.

 

[kbs2244]

The first and cheapest thing to do is get some of the old style "whitewash" and paint the roof.
It is just lime and water. Should be no EPA type problems.
It will wash off in the heavy fall rains.
Greenhouses used to do this in the summer, until motorized shade systems became popular.
As a second step, try some of the square "mushroom" type roof vents near the high side.
You will need to cut a 8 inch hole in the roof.
They will let the hot air out and keep the rain out.
The third step would be the foil.

 

[kf4zht]

WHen you say open rafter, do you mean there is no drywall on what would be the joists or do you mean there are no joists (i.e. a cathedral style ceiling)? If you mean the former, you'd have to drywall the underside of the joists and insulate on top. If you mean the latter, you'll can insulate the rafter cavities but you have to be very careful to allow a ventilation path between the insulation and the underside of the roof sheathing in order to prevent ice daming, mold/mildew/condensation damage ,etc (assuming this is a traditional hot roof design).

Short summary is there is nothing cheap to do unless you get the materials free.

No drywall on what would have been the joists. There was some thin (maybe 1/4') sheeting on it when we moved in. We removed it to capture the space in the ceiling, it was sagging badly and the garage has a low roof. Having the paneling in place made the garage seem very very small.

The foil seems to be a good option on paper. It is cheap, easy to do without making a mess of all the equipment in the garage, quick (do it at night) and may even help increase the light in the garage. I do not know how well it would work on its own, but the theory seems sound as long as we add proper venting for the hot air.

Has anyone used just the foil on its own?

 

[ddawg16]

I would go with the vent first....Just giving the heat an escape route will do wonders.

 

[UnionWelder]

paint the roof with white reflective roof paint worked in my shed

 

[Snowbound]

A fellow on theBuick forum I frequent has an electric ventilation fan in the attic and flips the switch a couple hours before heading out to work in the garage. Pulls all the hot air out and cools off the space.

Even sheeting the ceiling with drywall made a HUGE difference in my garage, just keeping the hot air up in the attic and out of the garage. I don't have the attic insulated yet. If I stand under the attic access hatch you can feel the hot air pouring out of there.

Get some of that foil and staple it up to the rafters and tape all the seems with foiltape. I bet you will see a difference. Add the roof vents too.

Brian

 

[UnionWelder]

power attic vent from lowes was 60 bucks little 1/25 hp motor and temp control built in..

 

[kbs2244]

The square one are less then $15.00
For $60.00 he could put in 4 and not have to worry about wireing.