In the small house the designer has the choice of either placing these roofs above the second floor or placing the second floor within the roof. Where the former is selected he sets for himself a very difficult architectural problem—that of trying to make the proportions of a house limited in ground area fit under a roof placed too high. This has rarely been solved with any satisfaction, for in nearly all cases the house looks too high and stilted. The comparative drawings show how true this is. Notice how house _A_ and _B_ look stilted, while house _C_ has a charm which no manner of designing would ever add to the former. Is it not a fact to be reckoned with that the small house is best solved architecturally if the second floor is placed within the roof? Economy of material is certainly secured in this way, and the construction is greatly simplified. The chief difficulties are to properly ventilate these rooms under the roof, and to give them good lighting without making too many and too large dormers. This is a hard problem, but it has been solved successfully. The Dutch gambrel roof was developed for this purpose, and there has been no doubt as to its beauty, except when wrongly used by placing it above the second story or poking the second floor through it in one long, single dormer. [Illustration: VARIATIONS OF DESIGN DEVELOPED FROM THE FEW FUNDAMENTAL STRUCTURAL MOTIFS] It is quite evident from the above how important the roof designing is in the small house. It goes without saying that the simplest arrangement of roofs is the cheapest to build and the easiest to maintain. Every valley means a leak at some later date, for as careful as may be the builder, the history of roof valleys shows that they leak sooner or later. The designer cannot freely mix his roofs either. Gambrel roofs, hip roofs, and gabled roofs do not go together harmoniously, without considerable study, and as a general rule they should not be required to do so. The usual methods of construction of these types of roofs are indicated well enough in the drawings and need no explanation. The ridge-poles in all cases are not of any structural importance, but act as alignments for rafters. For this reason they are made only an inch thick. Hip rafters have much the same function in hip roofs. Whenever valley rafters are needed, these must be designed like floor girders. If dormers are built into the roof, it is customary to double the rafters around the openings. Where gable dormers are constructed, one of the valley rafters must be extended to the ridge-pole, or else the rafters will collapse. [Illustration: GAMBREL ROOF CONSTRUCTION] [Illustration: CONSTRUCTION OF GABLE ROOF] [Illustration: HIP ROOF CONSTRUCTION] [Illustration] [Illustration: CONSTRUCTION OF A DORMER]