CONSTRUCTION TECHNOLOGY

Contraction Methods



Contraction Methods

Introduction

The construction industry is not, as commonly considered, a stereotyped industry with only traditional and conventional technologies. Firms in the construction industry have adopted new management practices, cost strategies, changes in design and new technologies related to materials, equipment and components.(Gann, 2002, 226-31) Although innovation in construction takes place incrementally, over the long term technological and organizational changes amount to dramatic transformations. Since the 1950s, these transformations include changes in materials, industrialization (standardization and prefabrication), use of IT in design and in construction (automation and robotics) and changes in supply chain management.

Cocntruction methods

Stick frame

This is the most common construction method used in the U.S.  In stick frame construction, the majority of the structural pieces are small and so the building is made up of very many of these small pieces (ie sticks) placed fairly close together which combine to achieve the overall strength.  These pieces are usually wood, but sometimes are steel. As the pieces get larger and the distance between them greater, it is no longer called stick framing, and instead becomes post and beam system.  Of course, various combinations of the two are also possible.

Stick frame construction is popular because the most common technique, platform framing, allows the use of many standardized pieces of wood and can be done relatively easily and rapidly.  In platform framing, each floor is built separately, one on top of another, and then the roof is added on the top.  The downside of stick framing is that the framing pieces only serve to hold the building up: they don't insulate, keep out rain or resist wind, so other materials must be added to perform those functions.  Typically plywood or a comparable sheet good (like OSB) is used to provide stiffness against wind loads, and some insulating material is filled in-between the 2x4s to give heat resisting, and then entire exterior is covered in a water resistant siding.

Post and Beam and Timber Frame

A post and beam structure differs from a standard "stick frame" structure in that rather than using smaller size lumber like 2x4s or 2x6s spaced 16 or 24 inches apart, it uses more sizable lumber like 4x4s and 6x6s or larger spaced 4 feet or more apart.  Structurally, timber framing is a post and beam method, and although traditional timber framing didn't use nails, there is not a significant difference between  the two. The biggest difference in in  implication: in timber framing the large dimensional pieces of lumber are usually left exposed, while a in a post and beam they may or may not be exposed.

Timber frame or post and beam structures are very commonly used in strawbale, cob and light clay buildings.  Timber framing is also combined with SIPs, although this is obviously overkill since building with SIPs generally requires few structural members.

There are various claims out there that timber framing uses less wood than stick framing, but it does not appear that this happens very often in ...