Reduce those attic temperatures with
Radiant Barrier Paint

The first thing you will need to know is how much Hy-Tech #85 Barrier Coat (Radiant Barrier Paint) you will need. There are two methods you can use, the pros shortcut... or the exact method.

Shortcut: This works for most situations where the gables or hips portions are 8'-10' in height.

Length of home x width, add 20%, then divide that number by 150 for the number of gallons of paint needed to apply the recommended two coats.

The Exact Method: We need 3 measurements and we will be referencing the fig. below.
  1. The length of the house, (this is not shown in the figure but you need it later).
  2. The number for "a" in the figure which is only 1/2 of the width, of your home.
  3. And we need to know the measurement for "c" in the fig., which is the measurement from the edge of the roof to the top or "ridge".

We are going to use a calculator for this one.
(Fig. 1)

Start by measuring the length and 1/2 of the width of your house, write it down.
Now measure how high it is from the top (ridge) of your roof to where the gable end meets the house, that is measurement "b".
Do this by going outside to the gable end, slide a stiff 1" measuring tape up the wall and record the measurement from the top to where the gable meets the house, "height" Write it down, this is measurement "b" in the fig.

(Fig. of how to measure your roof area)

Now I am going to send you to a calculator on-line (a new window will open, do the calculation and close out the window to return here):
  1. You will need to put in the number for roof "height" which is "b" in Fig. 1.
  2. The number for 1/2 the width (length of base) or "a" in the Fig. 1.
  3. When you get there you will see a little box on side "c", put a ? mark in the box.

Go there and get that number "c" in the fig.,which is the measurement from the edge of the roof to the top.

Take that number "c" that you just got from the calculator, (it should be just a little higher than the number "a"), multiply that by the total length of the house, multiply that by 2 and you have the total square footage of your attic roof decking that needs to be coated.

Barrier Coat covers appx 200 square feet per gallon so take the total square footage of your attic (you just figured it), and divide it by 200, the result is how many gallons of paint you need per coat, two coats are recommended so double that amount for the total gallons you need to order.

Hy-Tech #85 Barrier Coat can be applied by brush, roller or spray. We recommend spraying using an airless spray unit. Rent an airless from your local paint store, tool rental shop, and in some areas; Home Depot stores and follow the instructions in our
How to spray Paint Tutorial, it's fast, economical, and a lot easier than you might think.