93 



same to build a battened double-boarded wall with unmatched boards, 

 solid together with paper between, as it does to make two single walls of 

 matched boards with one lining of paper and the space stuffed with straw. 



Double-boarded walls can be used to good advantage by stuffing the 

 space with straw and separating the inside boards one-half to one inch, 

 thus allowing a change of air within the straw-packed enclosure. Such 

 construction is necessary only in the coldest regions, and then only on 

 the exposed sides. In addition to being expensive this double construc- 

 tion with straw packing is objectionable mainly because it furnishes a 

 breeding place for lice and mites. For this reason the sides of the house 

 that are in contact with the roosting and nesting compartment should 

 always be made smooth and tight. 



When the roosts are placed in the back of the pen it is well to protect 

 the fowls from the extreme cold by double-boarding, above mentioned, 

 or by an arrangement as shown in the illustrations (Figs. 50 and 58, 

 61, 64), in which there is an open air passage between the two walls 

 from about 2 feet above the floor to part way up the rafters above. This 

 construction allows a circulation of air between the two walls and pre- 

 vents the cold air on the north from penetrating to the inner chamber, 

 thereby providing greater comfort to the fowls when on the roosts. In 

 the latter instance, summer ventilation can be greatly perfected by using 

 long, narrow trap doors in the rear wall which open near the plate into 

 the air space between the double walls, and allow a passage of air up 

 through this air shute above the roosting room or below the nests into 

 the pen, without creating a draught on the fowls, as shown in Figs. 58, 

 61, and 64. 



The rear wall should be as low as is consistent with needed head room. 

 The low back not only makes the construction cheaper, but by reducing 

 the volume of air and minimizing the northern vertical exposure the 

 house is made warmer. 



Front walls may be of comparatively loose construction if the back 

 wall, ends, roof and floor are tight. Slow change of air takes place 

 when only the front wall is of open construction. This is on the principle 

 that it is difficult for air to enter and leave the house through the same 

 opening. The front wall, for the most part, will be used for windows 

 and cloth- or wire-covered openings. 



Ceiling 



It is seldom desirable to ceil the roof of a poultry house because of the 

 demand for economy in construction. This is especially true iri 

 the shed-type house. In building the gable or combination roof, however, 



