Considerations in Constructin$ a Poultry House For California.

J. E. Dougherty, Associate Professor of Poultry Husbandry, IJniversity of California

Ttre fundamental purpose of a poultry house is to provide a comfortable and healthful environment for the fot'ls at minimum cost. Design and operation are the chief factors controlling the environment provided and the labor cost of caring ior the birds. Depreciation and cost of upkeep determine the economy of the construction and of the materials used.

A poultry house should be so designed and built that it rvill 6e abli to cope rvith the severest storms likely to occur and remain storm-tight. Can one expect high priced rvinter eggs from chilled, bedraggled hens in a house, the interioi6f which is rain'soaked by every heavy storm ?

It should have a ventilation system that rvill (1) not only Drevent moisture condensation in r'vinter, eliminate drafts, and utilize the heat produced in the house as effectively. as possible in warming the air on cold days, thus increasing ihe comfort of the-birds, (2) but also bring about rapid heat removal and maximum air movement in hot, summer weather. Heating the air increases its drying action, for every 27"-fi' F. rise in temperature d.oubles its moisture .rrrying capacity. Moisture condensation in winter makes for i cold, -uncomfortable environment and produces wet litter which must be replaced. Cold hens do not lay. Too frequent renewal of the floor litter increases the cost of opeiation. In summer, on the other hand, speedy heat removal and maximum air movement during the heat of the day should be the aim. Poor summer ventilation increases the death loss due to heat prostration and lessens prodttction in hot weather'

A poultry house should be so designed and built that it will idmit the maximum amount of winter sunlight. Sunlight convevs warmth and cheer and the beneficial ultraviolet tays which are so valuable in promoting health and the qualiiy production of eggs. lfhe University type poultry house uies a shed roof providing a high, open front.and is- faced south, in order to allorv a maximum of direct sunlight to enter.

Insulation of the roof and even of the side lvalls may prove to be of distinct economic value in making a poultry itoo." warmer in rvinter and cooler in summer to the end that more dollars worth of eggs are produced each year and fewer bifds die. The Divisions of Poultry Husbandry and Agricultural Engineering of the University ofCalifornia i.. no* engaged in a detailed study of the value.of insulation for a poirltry house as a part of extended studies in poultry house design.

A poultry house should be so designed and built for convenience oi operation that every unit of labor will be most efiectively used. A well drained, very smooth surfaced floor requires less labor to clean and keep sanitary than one thaf is rough and poorly drained. The degree of smoothness will-materially influence the labor required in cleaning.

In cJmmercial egg farming a long house has been found more convenient than individual houses because (1) one is rvorking under cover most of the time and (2) a litter carrier catt be used to advantage in cleaning droppings boards, gathering eggs, feeding, etc', (3) rtrnning water and. electric light can be installed at least cost, (4) operations are moie concentrated, etc. In designing a long poultry house, therefore, these operating conveniences must be considered and their utilization within feasible lim.its taken care of. The roof, for example, must be made strong enough to support a litter carrier load of 500 lbs., the doors prop6rly localed and hung for the most convenient use of a iu.ii"r.- The droppings board and carrier must also be made to work togelhei most efiectively in expediting the cleaning of the droppings.

A poultry house should be so. designed and built as to make the lirgest return on the investment. In designing the University type poultry house and determining on materials best adapted to its construction, the health and comfort of the hen lvere given first consideration. Then convenience or the saving of time and effort so that more work could be accomplishe-<l per man hour of labor rvas considered and the third consideration was the effect of the construction and of the materials used on both the initial cost and the rate of depreciation.

It has been found to be practicable to reduce the floor space allorved per hen from 3% tq,. ft- _in the case of the light breeds to 2 sq. ft. as the number of birds kept togeth_er in-one unit is increased from 50 or less to 200 or more. In the. case of the dual purpose breeds, one foot more is allowed per bird than for birds like Leghorns because they are larger and require more room.

To illustrate why the floor space per hen must be large in small pens and ian be reduced as the size of the Pen is increased, let us consider a house 14 feet deep and 50 feet long divided into five pens, each contailing 4O. T-eghorns. Thd average floor space per hen in each 10x14 ft. pen-is 3l sq. ft. If trvo of these pens were thrown together by removing a partition, each bird would have,two pens to use instead of one and have twice as much floor space to wander over. If three pens were thrown together, each bird would have three timei as much floor space as it had in the original pen and so on. lt is evident, then, that increasing thJsize bi ttre pen increases the total floor space available to each bird. Because of this fact the average floor space per bird can be reducecl a certain amount rvithout harm to the stock since each bird will have a much larger floor space to exercise in than it had in the smaller pen. While crowding is detrimental, giving birds more house room than they can efiectively use increases investment and operating costs. Reducing the floor.space Per hen by increasing the size of the pen decreases the cost of construction per hen capacity until the minimurn is reached. If this minimum is adhered to there is no saving in enlarging the pen unduly and there may be a loss dtte to increased hazard frcm disease, etc.

It is not enottgh, holtrever, to consider only floor space in determining the hen capacity of a poultry house or pen within that house. Sufficient roosting space must also be provided. For light breeds such as Leghorns eight linear inches is the optimum amount of roosting space per bird. The roosts themselves should be 12 inches on centers, the rear roo-st 9 inches from the wall and the front roost 5 to 6 inches from the front edge of the droppings board. The number of birds will determine the number of roosts re-_ quired and the number of roosts will determine the size of ' droppings board and how convenient it will be to reach across to clean.

The low walls of a poultry house readily lend themselves to placing siding lumber vertically and to the use of short lengths of lumber. When placed vertically and well nailed, vertical siding will support much of the weight of the rooi so that the studding can be spaced farther aplrt than could be done if the siding were placed horizontllly. Surfaced tongue and groove lumber laid vertically is, tlierefore, recommended for the exterior walls of a poultry house.

Tongue an4 groove flooring, for example. that would be unfit to use in building a good floor beiause of the short lengths and such defects aJ slash grain, pitch pockets and small, .tight knots, makes excellent siding foi a p,oultry house if laid vertically s_o that rain will ,ur,"do*r, ttri lointt and not across them. Such low grade flooring whic'h has been sorted out of the better gracl-es as inferioi because of the defects indicated, may sell-for less than common, rough 1x12 inch bo.ar.ds i y_et- the defects in this flooring 'd; ;%a rn any .way_ injure it for use in siding poultry h6uses. It lays up well and makes a tight wall. It is surfaced so that it takes less material_ and libor to paint it than ao ,ough boards. It offers a less favorable 'environment for par?- sites. Floor.in-g of this kind is also less expensive,'as a 1u.le, than shiplap of equal grade and the tongue and groove .;ornt rs tighter than the lap joint.

To increase air circulation in hot weather, openings in the rear wall near the floor have been found'veiy teipfuf. The windows in the rear wall below the droppirig, U'o"ra in the University type house, therefore, ..r". . doible pur- pose. They light the floor under the droppings board Lnd w-hen they are opened on hot, summer days, the circulation of air over the floor and through the house is materially increased. This adds to the coirfbrt of the birds.

The ultra-violet rays in sunlight, as previously pointed out, have been found to possess propertils similai tb those of vitamin D in bringing about i normal utilization of the calcium and phosphorous consumed in the ration. therebv preventing rickets, aiding in the fullest production of eggs of good.shell quality,_and promoting heaith. Sunlight, hJirever, wh.ich passes through ordiniry window gi-ass loses. most of its value in this respect beciuse windoi, glass fil- ters out nearly all of these beneficial ultrajviolet ravs. Clean, loosely -*oven muslin probably trr".-itr-.;;ri;;;- able solar ultra-violet light, for the Kansas Station (1926) found.that 33 per cent of the ultra-violet rays ln sunt;ght passed throu-gh medium weight muslin w[ereas 25 ler cent passed through cel-o-glass and only l0 per cent pasied through glass cloth. The heavier the- muslin used. however, and the more filled the pores of the cloth become with dust and dirt, the more impervious it undoubtedly is td the ultra-violet rays of the sun. Muslin is also ,,6t .rr.rn dut'able. for it tears and rots when exposed to the weathe'i and must be replaced every two or three years.

These facts have given rise to a widespread demand for a durable substitute for glass- and muslin that would prove effective- over long periods in transmitting the ultra-i,iolet rays, ot the sun rnto a poultry house. There are now on the market q,uite a number of these products which are being more or less extensively used and in the comparative mer-_ its of which poultrymen are keenly interested-.

The U. S. Bureau of Standards and the Iowa Experiment S.tation have completed tests of a number of these ;1;;.-;;i;: strtutes and their findings show that these materEh trarrs- mit the ultra-violet partbf direct sunlight about as follows:

)creen _glass .. . .Approximately I5/o Cel-o-glass Aff roxima tetv ZOm Glass fabric .Approxim "trti SOi.-;h;; ;; Glasscloth ....i. .Apprqximarci;--i% flgxograss . .Abb,.;i;;tiilv z\f. Window glass : .Approxim "t tv tim Cel-o-glass, screen glass and similar proa;.i; ;;; *la"i, coatrng garvanrzed rvindow screen cloth with a cellulosl preparation such as cellulose acetate. Glass cloth, Fil;;: glass, glass fabric dnd similar products consist of a loose_ ly woven muslin coated with a'paraffin preparation. ., Roofing paper is one of the most eclnomical materiars rnar can be used tor a.poultry house roof. If a good grade of. 3 ply pap.er is used.^and i[ is coated every 2-or 3 -v."il wrth a good quality of asphalt- roofing paint co"tal"ing asbestos. it should last indehnitely insof-aias deterioratioi of the p-aper itself is.concerned. :f'tr. .iog"" : ,,Save tho sur_ face- and you save all", applies .u.., rnor.- f"r"ibfy to , ;;|e, roof than it does to lum6er.

!"yils roofing paper up and down the roof so that the strlps ot paper extend across the roofing boards rather than p.arallel to them insures ob-taining u ,rior. solid naiiin;-;i the paper. When the roofing is-laid far"il.i tolil'?";i boards, so many roofing,nails"are driveri "for. tog.tfr., i"io one board throughout the entire length of that i;;;; ;i;;; lr, rs very apt to split and the nails are loosened. A Iap mav atso occur at a crack between boards unless this possibii_ ity is consid,ered and.prevented befo." n"gi""i"giJia"|'il; paper. With the strips of roofing paper ixtend-ine up and dog'n the roof, the lihe of naits iotd^ing """h l;; ."i.;; across the boards and the nails are suffiiiently f"; ,p";-i; each board so,that there is much less risk'of .i!";r;; boards,; The lafii.ithould be laid in -ii" o,...,,on ot the heavlest wrnds; then these winds will not blow against the l?ps and tend to tear the paper loose.

.*Thi: papgr was presented 6efbre the annual convention ot the State Lumbermen's Association at the palace Hotel, San Francisco, November 8, l9D, as a part of the "eri"ulj tural program put on by the University of California.----

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