GREENHOUSES 



ported by a truss work, thus doing away with 

 all interior posts (sometimes known as truss- 

 frame). (3) A combination of the above 

 forms (known as a combination truss-frame) 

 is used in houses so wide as to make the 

 truss-frame impractical. This is commonly 

 used in houses over 40 feet in width. 



Fig. S3. Section of combination truss-frame green- 

 house, 172 feet wide 



As has already been mentioned, all-metal 

 frame houses usually have wood sash bars 

 and glazing bars, but they are not considered 

 as parts of the framework. In these houses 

 the completed framework is entirely of metal, 

 the wooden members being fastened to the 

 frame with bolts or screws and serving only 

 to hold the glass in place. 



In many all-metal frame houses, especially 

 when the roof is supported by inside posts, it 

 is common to bolt an iron or steel sill to the 

 wall and then bolt the side posts to this sill. 



A method of erecting a modern combina- 

 tion-truss frame house, 73 feet wide and 



