If your house needs a new roof, you may save some money by doing the job yourself, if:
* You're an experienced carpenter.
* You can work comfortably at heights for a long time.
* The roof isn't too steep, and there aren't a lot of angles and planes formed by dormers and gables.
* You have the stamina, patience, and time to do the job as it should be done.
First check to see if you need a building permit. Then be sure to follow the manufacturer's application instructions all the way. Do not take short cuts to save time. If you follow the rules, you should get an attractive, weathertight, durable roof.
To determine the slope of your roof, measure how many inches the roof rises for each foot it runs. Slopes of 4 to 5 inches per horizontal foot are the easiest and safest for do-it-yourselfers. Steeper slopes are difficult and risky. Lower slopes call for special procedures.
Since roofing shingles are sold by the square, determine the number of squares needed to do the job. One square covers 100 square feet. Multiply the length of the roof by the width. Add 10 percent for waste and divide the total by 100.
Basic reroofing tools include gloves, carpenter's apron, hammer, roofing nails, utility knife, cementing trowel, tape measure, and chalk line. A tall, sturdy ladder and secure scaffolding are essential for safety. A safety harness is also recommended.
For safety, secure ladders at both the top and bottom, and be certain they are well away from any power lines. Wear rubber-soled construction-type shoes. Lift only light loads, and work on the roof only when it is dry.
Apply shingles on clear, warm days, but not when it is hot, rainy, windy, or below 40 degrees F. Place the shingles and tools where they won't slide off the roof, and keep the roof free of debris.
For further information, ask your local building-materials supplier, or send 50 cents to the Asphalt Roof Manufacturers Association, PO Box 3248, Grand Central Station, New York, N.Y. 10163.