WOOD-AND-IRON BUILDINGS 79 



In cottage work the posts or verticals should not be further apart 

 than five feet, but in buildings such as sheds they may be placed 

 much further apart. 



If the woodwork be creosoted, the life of a wood and iron 

 building will be considerably lengthened. 



The Iron Work. — The iron sheathing consists of sheets of corrugated 

 iron, which are usually continuous from foundation to eaves (Figs. 

 109 and 112). The sheets of iron are nailed to the horizontals of 

 the wooden frame-work with galvanised iron screws, each of which 

 is provided with a galvanised iron washer and also a lead washer. As 

 is done in the case of roofs, the lead washer is placed below the 

 galvanised iron one. 



For corrugated iron sheets up to 8 feet in length, one rail between 

 roof-plate and foundation-plate is sufficient, but for sheets longer than 

 this, two rails should be provided to which, as well as to the roof- 

 and foundation-plates, the iron may be nailed. 



As in roof work the sheets of iron are fixed so that both edges of 

 alternate sheets lap over on top of the sheets between them. Thus 

 there is an upper and an under sheet alternately, similar to the arrange- 

 ment shown in Fig. 60. It is desirable that the corrugated iron 

 should be nailed to each horizontal by screws passing through alternate 

 corrugation ridges. It will be found, however, that this method of spacing 

 the screws does not always work out so that we get a screw passing 

 through the joint at each end of a sheet. To effect this object it is occa- 

 sionally allowable to leave two adjacent corrugation ridges un-nailed. 



Doors and Windows in Corrugated Iron Buildings. — The manner in 

 which doors and windows are fitted into corrugated iron buildings is 

 dealt with in the next chapter. 



Wood-lined Iron Buildings. — In order to make iron buildings less 

 hot in summer and less cold in winter they may be wood-lined. For 

 this purpose ceiling boards, nailed to the inner faces of the timbers 

 composing the framing, are generally used. 



Brick-lined Iron Buildings. — With the above object in view, a 

 brick lining may be adopted in place of the wood lining 

 mentioned in the above paragraph. The bricks are laid on their 

 faces, so as to fill up the rectangular spaces between the horizontals 

 and verticals of the timber framework. The brickwork is 4£ inches 

 thick, stretcher bond being employed. 



