Roofs for Farm-Buildings, 141 



are also given, not as thoroughly good roofs, but to show that, if 

 reduced cost be the object, a light roof calculated to last for 

 a number of years, and free frora many of the ol)jections to 

 iron as a heat conductor, &c., can be easily put up at a still 

 smaller cost. 



II. The employment of iron instead of timber in the framing 

 or main construction of a building is advantageous, when a 

 building exceeding 30 or 35 feet in width has to be roofed without 

 internal supports. In tlie buildings of an ordinary homestead 

 there is none that admits of such a span ; and in the case of 

 covered yards (the benefits of which are likely to be more and 

 more appreciated) although a single roof might be resorted to, 

 yet advantage may always be taken of a line of fencing for a set 

 of story-posts or columns without interfering with the yards, and 

 a series of open gables of moderate dimensions, with ornamental 

 barge-boards, may be made to present a more pleasing elevation 

 than a higher roof in one span, whilst its cost will always be less 

 whether of iron or timber. Good and efficient roofs of moderate 

 span, such as suit a farm, may be easily framed either in timber or 

 iron. On the score of appearance there will be little to choose 

 between them ; from the outside the roof-timbers are entirely 

 invisible, even in the case of an open gable being concealed by 

 a barge-board, and as to the look of the outside, tastes may well 

 differ. 



Some proprietors may be influenced by the consideration that 

 timber can be found upon the estate, but I attach no weight to 

 this, because I am fully satisfied that roofs should always be 

 framed from foreign fir, that of English growth being reserved 

 for weather-boards, fencing, and other purposes, where its warp- 

 ing will not involve serious damage to the main structure of 

 the building ; I have known numerous instances in which a new 

 roof has been required after only a few years, in consequence 

 of the injudicious saving of the few pence per foot, which re- 

 present the difference in price between English and foreign 

 timber. 



Whether a roof be framed of sound foreign fir, or of rolled and 

 wrought iron, it should, if properly treated, be nearly equally 

 durable ; on the one hand the iron will require occasional 

 painting to prevent rust (of which 40 tons are said to have been 

 scraped off the Britannia Bridge) ; on the other, if the roof- 

 covering is neglected, and the rain allowed to run down the 

 timbers, the Avood will perhaps first suffer ; but except through 

 negligence, either may be considered as practically permanent. 



Unless every part of a building is of fire-proof construction, 

 there is no special advantage in a roof framed of iron. For a fire 

 can hardly originate in the roof-timbers, whilst when a fire has 



