Flitch beam
The word 'flitch' refers to a plank of timber, cut lengthways from a tree trunk. It is related to the word 'flesh'.
A flitch beam is a compound beam commonly used in loft conversions and other timber-frame structures where longer spans are required than solid timber is able to provide.
Flitch beams consist of a steel plate sandwiched between two solid timber members and bolted together. Further alternating layers of timber and steel can be used as required to increase the strength of the beam.
The benefit of using flitch beams is that they are lighter and cheaper than using only steel, and allow fixing of the surrounding timber framework using nails or screws. As they are significantly stronger than timber beams they require less depth than a timber-only beam of the same strength.
In contemporary construction, the use of flitch beams has fallen into decline. This is largely due to the high cost of labour involved in their manufacture, and the introduction of high-strength engineered lumber and glulam beams. However, they can still be used to offer design versatility, and in renovation works where a structure needs to be altered or strengthened without increasing its depth or underlying construction.
TRADA have developed the TRADA Flitch Beam Designer, a software program that allows users to design flitch beams using current British timber and steel codes.
[edit] Find out more
[edit] Related articles on Designing Buildings Wiki
Featured articles and news
Conservation in the heritage cities of Venice and Liverpool.
Which room is the most fun to design? Find out the 'Grand Designs' presenter's unusual choice in our interview.
Full suite of speakers are announced for this year's BSRIA Briefing event.
Book your place for the Architectural Technology Awards 2018.
There are many ways of classifying types of building. Have a look at our range of building articles.
BSRIA have launched the 'major update' of the go-to design framework guide for building services.
How to get results with building life cycle assessment.
Government publishes a prospectus inviting proposals for new 'garden communities'.
The Morandi motorway bridge in Genoa collapses during rainstorm while undergoing maintenance works.
'Developed design' is a phrase coined by the RIBA for their 2013 Plan of Work. But what does it actually mean?
New green paper published aiming to rebalance the relationship between landlords and residents and tackle stigma.