Identify weakness in roof trusses

[miketheman2k]

I've recently moved into a bungalow and the surveyor told me the roof trusses could do with more bracing than they currently have. Pics attached of the current structure. The questions I have are:

- where is the weakness in this?

- what could the result be of leaving it?

- what would I need to fix it?

Thanks in advance.

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[theoldun]

Truss shown on drawing is a Fan truss, although you have not drawn in the bottom chord.
Fan trusses are used for longer than average roof spans..
Appears from the poor photos that there are no longitude braces or wind braces. Can not see whether there are any lateral braces to gable wall.
The weakness is that if you are in an exposed wind zone area, a freak gust of wind could repeat could lay your gable wall and roof down flat like a pack of cards as you are only relying on tile battens for bracing.
It is time consuming job but easy to fix, if you know how, but unfortunately most local small builders would not have a clue
Regards oldun.

 

[catlad]

What you need is some 4"x1" rough sawn timber as long as possible they should have gone in when the house was built and they would have used approx 16' lengths but you will not get those in your loft now, so use the longest you can get in and put four screws in each truss.

 

[ricky101]

Hi,

You might find these pictures /link of use, though not exactly the same as your 'fan' truss

http://www.uwe.port.ac.uk/roof/trussedrafters/section5.htm

https://www.google.co.uk/search?q=r...et-it-right-roofing%2F1032261.article;520;268