Bowed Cross Members

[deanalewis]

Hey Folks,

I had a surveyor out to view a property I am planning to buy and they mentioned bowing Cross Members not on the Purlins indicating excessive weight and to get a structural survey.

Are my right in thinking that they are likely just covering their arse and someone just just rested something heavy on the cross members. Like I mean the idea of those chunks of timber is to stop the roof pulling apart so how could they bow would they not be under horizontal stress with anything the purlins pulling them to keep it rigid?

Anyway what type of cost is involved in putting a few more cross members across the roof. Is it just case of throwing an extra few along additional purlins to give it strength?

 

[Wayners]

I've jacked up joists and screwed cross beams across to straighten.
Also added timbers supports and bolted timber to the sides to strengthen.

Got any pictures?

 

[deanalewis]

In the picture with the expansion vessel you can see an older expansion tank that looks to be supported in an L fashion to the purlin and to the roof. Perhaps over years of that being used it caused stress on that part of the roof due to the weight of water which would have pulled the purlin downwards. EDIT: On closer expension it looks like the red expansion vessel is also holding on with that tiny bracket.