14 N. H. Agricultural Experiment Station [Bulletin 303 



HOUSE ** 1 3 HOUSE » 1 4 HOUSE ^1 5 HOUSE « 1 6 



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Fig. 6. A series of floor temperature readings taken with the thermocouples 

 between night and morning in the four kinds of floors used, during a drop in 

 outside temperature from +10°F. to — 14°F. 



as far as variations are concerned, but no improvement in floor surface 

 temperatures under the brooder. Hence, this is considered to be the 

 point of declining eiRciency of insulation. 



It has become evident from a study of the above curves that differ- 

 ent sources and degrees of exposure are in effect on brooder house floors. 

 Ground temperature, ice formed under the house, outside temperature 

 penetrating "banking-up" material, leaks in "banking-up" material, 

 room temperature above the floor and floor drafts are the important 

 sources of cold which gain entrance to the floor surface under the 

 brooder. 



The amount of exposure of the upper floor surface to the tempera- 

 ture of the air in the house also has an effect on this brooder floor con- 

 dition. For about one-third of the daylight hours, absorption of heat 

 from the sun's rays may benefit temperature conditions on the floor. 

 As this occurs at the time chicks are out on the litter, its value cannot 

 be other than beneficial and it is available at an appropriate time. 



For 16 hours, approximately, the effect of the air in the house will 

 be in the opposite direction and exert a lowering influence on the floor- 

 under-brooder temperature. A hold-over advantage after the eight 

 hours of sunshine is believed to play a part in keeping this temperature 

 on the upward trend until the midnight period, by which time this has 

 been overcome by the opposite action of the house air after sundown. 

 High wind pressures, when they occur, counteract the sun 's action. 



