The purpose of a roof is to keep the weather out of a house, an umbrella on a wet day and a parasol on a hot day. The kind of roof that is best for a particular house will depend on many things. The preference of the owner should first be considered. Although good roofs are sometimes made of grass, palm leaves, or cedar bark, these are not commonly used in America.



The principal things to consider besides the taste of the owner in selecting a roofing material are the first cost, the appearance of the roof, how long it will last, how much maintenance or upkeep it will require, how fireproof or fire resisting it is, what insulating value it has, and most important, will it really keep the house dry even during driving heavy rains or periods of excessive snow.

How steep should the roof pitch be? That depends on the effect you want. The steepness, or pitch, of a roof will determine what type of roofing should be used. A roof composed of small pieces of material, as shingles or slate, should seldom have a slope of less than 5" rise per foot of horizontal distance covered.

One thing should be noted carefully: it is not the steep roofs that leak. When it comes to keeping out the rain, the more roof pitch the better. This has, however, practical limits; we do not want a house to look like a cathedral, and we do not want the roof area to become too large.

We may want a rather low appearance to the entire house, and a steep roof would be out of the question. Let us be reasonable about it, and if at all possible, keep the roof pitch at least as steep as 41/2" rise per foot, and preferably 5" or more; that is, if we want a roof made of shingles, slate, composition shingles, rigid asbestos shingles, or similar small pieces of material.

If a really flat appearance is desired, it will be necessary to use a built-up roof. Many roofs with a slope of less than 1/4" per foot are giving satisfactory service, but they might do better with 1/2" per foot slope. These flat roofs are what are called built-up roofs. That is, they are made of several layers of roofing felt cemented together with asphalt or coal tar pitch, and covered with a layer of gravel to keep the wind from disturbing the roof, and to keep the sunlight from causing deterioration of the asphalt and felt.

This roof depends for its effectiveness on its being one piece of impervious material. Roofs of this type should never have a roof pitch greater than about 21/2" rise per foot, as they tend to slide down the slope when they expand on hot days, and are not strong enough to pull themselves back into shape when they contract at night.

It requires more care and skill to put on a good flat roof than it does to put on a steeper roof. I do not say that a flat roof will always leak, but I have had a lot more trouble with them than I have had with steep roofs.

Local customs, the materials available, the preference and prosperity of the owner, and the type of house, will have an influence on the type of roof se-lected.

High class workmanship and meticulous care about the details are the things that make a good roof, fully as much as the choice of materials.

In wet climates where it really rains, and rather often, it is hard to beat a roof of wood shingles. These can be of cedar, redwood, or cypress; but in many sections of the country builders feel that genuine red cedar shingles cut with the grain vertical are the most satisfactory.

Flat-grained shingles are not worth putting on as they tend to split, and usually in places to permit leaks. They can be used for undercoursing when shingles are put on walls.

Remember, choice of roofing can affect how you will always feel about the house ? take your time and make a good choice.