144 Roofs for Farm-Buildings. 



This makes a 2;ood incombustible roof, and with occasional painting, or some 

 preservative jjrocess, will last I'or a considerable time. The disadvantages are, 

 that lying hollow it soon buckles ; and in case of repair, it is difficult to make 

 a sound job without disturbing a great deal of the roofing. 



No, 4. — This roof is formed in a similar manner to the foregoing, but laid 

 on rafters, 31x2 in. (instead of purlins), 1 ft. 9 in. apart, rounded 

 on the edge. 2 purlins, 4} x 3i in. lUdge, 7 x lu in. 

 The cost of which is 51Z. 8s. M.* 



By the means of the rafters, the iron is dressed round them, and gives the 

 appearance of an Italian roof. This gives a stronger roof than the other ; the 

 sheets of iron being in less lengths are not so liable to buckle, and are easily 

 removed. 



No. 5. — A roof similar to No. 3, but formed of eight wrought-iron principals, of 



the following scantlings : — f in. diameter round iron tie and king 



rods, i in. "T-strutts, 4 in. area. | in. X-principals, 5 in. area. 



Purlins, 4^ x 2 in. Wall-plates, ridge and iron covering as before. 



The cost of which is 59^. 158. 3cZ.* 



No. 6. — Wrought iron principals as last, and covered as described in No. 4, 

 but with purlins, 4 x 3 in. 

 The cost of which is 63Z. 5s. Id. 



It will be thus clearly seen that the cost is increased from 12Z. to 15?. by 

 the use of iron instead of wood principals. 



No. 7. — A segmental roof formed of corrugated iron, No. 24 guage, Avith 

 eight f in. diameter tie and king rods. 

 The cost of which is 47/. ISs. 7c?.* 



The detail shows 14 squares in this instance, a segmental roof having more 

 surlace. 



The disadvantages of corrugated roofs are their liabihty to decay, their 

 extreme ugliness, and the difficulty in forming skylights, if so desired. 



No. 8, for Pantiling. — A roof constructed of six wood principals of the following 

 scantlings : — Tie-beam, 10 x 4 in. Principals, 6 x 4 in. Braces, 

 4 X 22 in. 2X5 in. straps and f in. bolts at feet of principals. 

 Wrought iron Iving-rod, 1 in. in diameter, and cast-iron head. 

 Wall-plates, 41 x 3 in. Ilidge, 7 x I5 in. Eafters, 1 ft. apart, 

 4 X 2^ in., on purlins, 8x4 in., and covered with pantiling, laid 

 dry on stout laths. 

 The cost of which is 44?. 12s. lOtZ.* 



Detail shows 12 j squares ; pantiling having no waste, not requiring very 

 much eaves or a very high slope. 



This I consider a cheap roof; very substantial and capable of easy repair ; 

 forming a warm covering to cattle-sheds, and one which may 

 be recommended wherever the appearance of pantiles is not ob- 

 jected to. 



No. 9, the same with iron introduced. — A roof formed of eight wrought-iron 

 principals of the ibllowing scantling : — 1 in. diameter tie and king 



* See for details of cost, pp. \\(>, 147. 



