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Table of Contents

12. Basement.—Economy and practical sense suggest a basement under the entire school building, for it allows of many advantageous combinations of arrangement and the use of every foot of available space. By keeping the basement floor well up to the grade line, with not more than three feet of excavation, and with a ceiling not less than ten feet in the clear, ample room for the distribution of plumbing pipes and heating ducts is provided. A well-considered basement, with good means of ventilation and good lighting, provides means of ventilation and under-drainage and is one of the most efficient means for preventing the rise of moisture in the walls and ground air rising into class rooms and corridors.

The schoolhouse basement is of incalculable benefit to the community, since advanced ideas in education have made it more than a coal hole and a repository for all the trash and junk that accumulates during the school term. Instead of being a catch-all, the basement now serves as a work-shop for the boys who have adopted vocational training as part of their school work. The girls, too, utilize the basement for their sewing and cooking rooms. The vocational training departments of the consolidated schools have proved popular innovations, and it is believed stand largely for the increased interest in general school work.

13. Drainage.—It is important in connection with the foundations of school buildings to see that means are taken to prevent as far as possible the conveying of moisture from the earth through capillary attraction and the subsequent conditions, "sweating" and cellar-like atmosphere so noticeable when the school is opened in the morning. It is a mistaken idea that if both floor and walls of a basement are thoroughly cemented, no water can get into it. Contrary to the belief of a great many people, it is not impervious to water, and under a comparatively slight pressure water will readily find its way through well-mixed concrete, unless waterproofed by some waterproofing compound. Unless, therefore, those who introduce basement floors into school buildings have placed the building on high land, with the ground sloping from it rapidly in all directions, they must encircle it with a drain as indicated in Fig. 1.

Drainage should be done with ordinary field tile, laid with slightly open joints, having the upper joints covered with a 2" strip of waterproofed paper or a layer of loose straw about 6" deep before being refilled with earth. The water finds its way into the drain from the bottom of the drain. The gravel, straw or waterproofed strips of paper over the top joints are to prevent the surrounding soil and small gravel entering the tile from the top. This should always be placed a little lower in the ground than the footings, so that the water line will never reach the walls for any length of time. It is never well to run drains under a basement floor, especially if they connect with a sewer. A drain outside will relieve all pressure from surface water. In extreme cases it is proper to place the drain about six or eight feet outside the foundation walls, and then, if the tiles are sufficiently large, and the pipes have sufficient fall to its outlet, the rain water down pipes from the roof can be connected to the drain with hub and spigot tile pipe with cemented joints.

15. Damp Course.—There should be a damp course of some suitable material, such as slate set in Portland cement mortar, asphalt or a coating of plastic cement having a strong bituminous base, or a layer of water-proof paper, bedded in the walls of basement or piers, otherwise dampness will find its way into walls above by capilliary action.

16. Class Rooms.—The comfort and health of a school depends largely on the proper arrangement of its class rooms. They may be regarded as the units of which a school building is composed, to which the other rooms are subsidiary.

17. Elementary School Rooms.—The standard size of elementary school rooms should be six hundred and thirty (630) square feet of floor area, with a ceiling height of not less than twelve (12) feet. The most satisfactory dimensions of such a room are:—

18. Schedule of Average Sizes of Class Rooms.—

			Rows of desks.
For 24 pupils:—	19' x 24' x 11'-0"		4
For 28 pupils:—	19' x 26' x 11'-4"		4
For 30 pupils:—	23' x 24' x 12'-0"		5
For 35 pupils:—	23' x 27' x 12'-0"		5
For 40 pupils:—	23' x 30' x 12'-0"		5
For 42 pupils:—	23' x 30' x 12'-4"	Primary.	6
	24' x 28' x 13'-0"	Grade.	6
For 48 pupils:—	23' x 33' x 12'-8"	Primary.	6
	24' x 32' x 13'-0"	Grade.	6

19. Desk Spacing.—Where four or five rows of desks are placed the above arrangement will permit of desks 1'-9" wide with aisles between of 18" having 3'-6" passage along window side. 4' passage on wall at pupils' blackboard with not less than 8' clear space at teacher's end and 4' behind rear desks.

Where 6 rows of desks are placed the spacing in a room 23' wide will be as follows:

1'-9" width of desk.

1'-4" space between desks.

2'-10" passage at window side.

3'-0" passage at inner wall.

In this latter case it will be seen that the dimensions of passages are somewhat restricted and that a room 24' wide could be better spaced. In rural schools where room heaters are used some of the desks will necessarily be omitted.

20. Height of Rooms.—No class room shall be less than 12' high throughout, except in rural school rooms for less than 29 pupils, where the height may be 11' throughout. Rooms partly ceiled on collars should be 10' high to wall plate, and 13' to ceiling. The flat ceiling should extend over at least half the area of the room. In no case may a class room be left open to the ridge.

These sizes apply to all rooms taught by one teacher. While the height of ceilings is less than that recommended by some authorities, it is a safe and economical standard for elementary schools, especially for rooms above the first floor.

One of the objections which will be urged against making the ceilings twelve feet in height is that it will deprive the pupils of air space and make the problem of ventilation more difficult. This objection may be fully answered when it is stated that any air space above twelve feet six inches in height is of no use as regards ventilation, since it remains unaffected by movements of the lower air in the room; nor is it required for light. Further, pupils need the same amount of fresh air per minute, whether they are in a large or small room, consequently after the initial supply is vitiated the same amount must be introduced in either case.

Where forced ventilation is used the only difference would be supplying a room twelve feet high and one twelve inches higher, and this difference is so small as to be negligible. As an offset to any further comments it may be well to indicate the advantages to be gained by lowering the ceilings and increasing the floor area of the class rooms.

In the first place the cost of the building should be considered. Every foot saved in the height of the building will reduce the cost much more than a casual calculation would indicate. Every foot added to the height of a class room adds so much expense in keeping it in repair, and especially in heating it, also heavier walls, higher chimneys and vent flues and longer stairways are required.

From the hygienic point of view there is no special disadvantage for boys, but it is an added hardship on adolescent girls. In case of fire there is also increased danger in high ceilings.

21. Seating Capacity.—The seating capacity of each class room with a twelve foot ceiling shall be determined by allowing not less than eighteen (18) feet of floor space for each pupil. The above-mentioned size of class room is recommended. However, class rooms having fifteen feet of floor space to each two hundred cubic feet of air space will be approved.

SIZE OF SINGLE DESKS

Height of seat.	Back to front.	Across width.	Age Accommodated.
12"	21"	19"	5 years to 8
13"	22"	19"	8 years to 12
14"	24"	21"	10 years to 15
15"	26"	21"	12 years to 18
16"	27"	24"	16 years to 20

22. Width of Class Room.—The width, where unilateral lighting is used should never exceed twice the distance from the floor to the top of the windows.

23. Lighting of Class Rooms.—Sunless rooms are apt to be dark and cheerless and recent experiments seem to show that contagious disease is mostly spread, not by germs flying in the air, but by direct carriers such as insects, food, drink, or mucous. Colds seem to be passed from one child to another through minute drops of mucous which are sprayed into the air in coughing or sneezing. The best way to avoid contagion is to flood every corner of the room with sunshine and so render these drops sterile.

In Ontario during the winter season twilight begins comparatively early in the afternoon. Where the shadows are long at noon and where cloudy, dark days are of frequent occurrence, it is probably a good plan to place the school building half way between the points of the compass so that all rooms may have sunlight during some part of the day.

24. Light Area Required.—School experts seem to agree that each class room requires an amount of window surface equal to one fourth of the floor area of the class room exclusive of mullions, sash, meeting rails and transoms. To ensure efficient lighting of the desks and blackboards by merely supplying the required amount of glass area is not enough. The position of the windows themselves have a great influence upon the complete lighting.

25. Unilateral Lighting.—Most authorities agree that class rooms should be lighted from the left side of the pupil only. With unilateral lighting it is far easier to arrange for adequate blackboard space and to place it opposite the light. Light from behind the teacher or pupils should under no circumstances be allowed. The glare of the light directly in the faces of pupils will cause discomfort and injury.

26. Breeze Windows.—It is sometimes deemed expedient to place one or more "breeze windows" high up at the back of the room for ventilation purposes only, to obtain a through draft, and protect these from the direct rays of the sun. There is no objection to this.

27. Bilateral Lighting.—The question is often asked: Why not have windows on both sides of a class room, for it is not possible to get too much well diffused light in a class room? Until very recently school buildings were constructed this way, and it is still very hard to convince some people that lighting from one side only is better than lighting from both sides.

28. Objections to Bilateral Lighting.—Suppose we consider a class room with East and West exposure, with the same number of windows on each side, located in the same relative positions. At 10. a.m. the light is stronger from the East than from the West, and the line where the light from each side is equally strong is well toward the west of the room, this line will shift towards the East side the rest of the day, reaching the center at noon. But at any time in the day there are always two shadows on the hand and pen. These shadows are of equal intensity only at this shifting line of equal light. To the left or right of this changing line one shadow is always stronger, and hence it is impossible to seat all pupils so as to give them equally good light for writing. There is no desk in the whole room where double shadows of the hand and pen may not be seen. For this reason it is impossible to seat all the pupils in a class room with bilateral lighting without imposing some slight hardship on all, and a serious hindrance on something less than half of them. There are other reasons why bilateral lighting is not to be preferred. The best place for the blackboard is opposite the source of light, and hence it should be placed on the wall of one side of the class room. A common custom has been to place the blackboards between the windows on both sides. Such a setting has been responsible for an untold amount of eye strain, headaches and habits of inattention. It is rational to conclude, then, that if unilateral lighting were not in accordance with the demands of hygiene it would still be wise to locate all the windows on one side, so that the other may be used for blackboards.

29. Sky-lighting.—Contrary to the usual belief, light coming from above the desks introduces more disturbing shadows than that coming from the left. For this reason alone lateral lighting is generally preferable in class rooms to sky-lighting, though the latter is often helpful in cities where tall buildings obstruct the light, or where troublesome reflections from outside of buildings are likely to overstimulate and fatigue the eyes.

30. Prismatic Glass.—In cases of existing schools where the class rooms are unsatisfactorily lighted, the illumination of the room can be greatly increased by the use of prismatic sheet glass, by means of which the light rays are caught up and thrown horizontally across the room. Care should be exercised to see that the glass is correctly set in position relative to its prisms so as to get best results.

31. Position of Windows.—In placing the windows it is of great importance, first that there should not be large space of wall showing between the back of the room and the first window: secondly, that there should be no wide piers between the windows to cast heavy shadows across the room. It is not possible to construct brick, tile or stone piers of sufficient strength in a building of any height that will not interfere considerably with the light. In order to meet these objections successfully, iron mullions may be used. (See Fig. No. 4.) In this way it is possible to assemble a cluster of windows together, at the same time supplying sufficient strength and more light.

32. Window Mullions.—Assuming the standard size class room to be 24' x 32' x 12'—twenty-four feet wide, thirty-two feet long, and twelve feet in height—the glass area to be equal to one-fourth of the floor area, we have one hundred and ninety-two square feet (192 sq. ft.) of glass area to place in a wall that is thirty-two feet long. If the windows are set four feet from the floor line and the tops of the windows extend to within six inches of the ceiling of the class room the height of the windows would be eight feet. Thus to get the amount of window surface demanded by the rule, twenty-four feet in length of this wall must be glass. This would leave only eight linear feet of wall space unused. The height of the window sill plays an important part in the question of lighting.

In the first place it should not be below the level of the tops of the desks, neither should they be so high that children are unable to see out. There is a dreary appearance given to a room where the window sills are too high, also a loss in lighting. School experts seem to agree that window sills set three feet six inches from the floor line to three feet nine inches, and four feet, should be regarded as a maximum height.

34. Exposed Beamed Ceilings.—Coved ceilings and exposed beams should be omitted in class rooms. They obstruct free circulation of air and form dead air pockets at the ceiling line.